Att C - MMWR Supplement Sample

Morbidity and Mortality Weekly Report
Supplement / Vol. 60

October 7, 2011

Public Health Then and Now:
Celebrating 50 Years of MMWR at CDC

January 15, 1993 / Vol. 42 / No. 1
CENTERS FOR DISEASE CONTROL
AND PREVENTION

1
4
5
7
14
17

Hepatitis E Amon g U.S. T ravelers, 1989–1992
Surveillance of Deaths Attributed to a
Nor’easter — December 1992
Respiratory Syncytial Virus Outbreak Activity
— United States, 1992
Condom Use and Sexual Identity
Am ong Men W ho Have Sex With Men —
Dallas, 1991
Surveillance of the Health Status
of Bhutanese Refugees — Nepal, 1992
Notice to Readers

Morbidity and Mortality Weekly Report
Weekly

Epidemiologic Notes and Reports

January 11, 2002 / Vol. 51 / No. 1

Rapid Assessment of Injuries Among Survivors of the Terrorist Attack
on the World Trade Center — New York City, September 2001

Hepatitis E Among U.S. Travelers, 1989–1992
Hepatitis E of
Outbreaks
— hepatitis
Continued
E (i.e., enterically transmitted non-A, non-B hepatitis) have

U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES

January 15, 1999 / Vol. 48 / No. 1
1
4

8
12

All-Terrain Vehicle-Related Deaths —
West Virginia, 1985–1997
False-Positive Laboratory Tests for
Cryptosporidium Involving an
Enzyme-Linked Immunosorbent Assay
— United States, November
1997–March 1998
Self-Reported Prevalence of Diabetes
Among Hispanics — United States,
1994–1997
Recommended Childhood Immunization
Schedule — United States, 1999

/ Public Health Service

All-Terrain Vehicle-Related Deaths — West Virginia, 1985–1997

of one or more drugs increased 61.0%, from 1,804 to 2,905,
and the death rate increased 47.5%, from 10.6 to 15.7 per
500
100,000 population.
During 2003–2009, death rates increased
INSIDE
for all substances
except cocaine
and heroin.
TheAfter
death
rate
Nutritional
Assessment
of Children
Severe
5
for prescription drugs
increased
84.2%,
fromJune
7.3 2001
to 13.4
per
Winter
Weather —
Mongolia,
0
40
42
100,000 population.
The greatest
increase serotype
was observed
in the
7
Outbreak
of Salmonella
Kottbus
Infections Associated
with Eating
Alfalfa
death rate from oxycodone
(264.6%),
followed
by Sprouts
alprazolam
9
Notices to Readers
(233.8%) and
methadone
(79.2%). By 2009, the number
of deaths involving prescription drugs was four times the
number involving illicit drugs. These findings indicate the
need to strengthen interventions aimed at reducing overdose
Disease
Control and Prevention
deaths from prescription drugs in Florida. Medical examiner
TM
• HEAL
THIER
HEALTHIER
• PEOPLE
records
are a timely,
population-based source for data regarding
overdose deaths from specific drugs. The data in this report
and subsequent analyses can be used to design and measure
the effectiveness of interventions.
Florida has a system of regional state medical examiners
whose jurisdiction includes all drug-related deaths. Drug
overdose data were obtained for the period 2003–2009 from
datasets of the Florida Medical Examiners Commission, which
contain information on 34 types of drugs frequently abused,
including ethanol (grain or beverage alcohol), prescription
drugs, and illicit drugs (4). Drug-related deaths are divided into
two categories: 1) drug-caused deaths, for which postmortem
medical examiner toxicology testing determined that drugs
were present in lethal amounts; and 2) drug-present deaths, for
which drugs were found in nonlethal amounts. This analysis

ATV-Related
From
1985 through
Deaths —
1997,
Continued
the U.S. Consumer Product Safety Commission (CPSC)
identified 113 deaths associated with all-terrain vehicles (ATVs)* in West Virginia. This
report summarizes data from the CPSC ATV-related death database and on-site and/or
follow-up telephone investigations; findings indicate that approximately two thirds of
deaths were caused by injury to the head or neck. Consistent use of helmets by riders
can substantially reduce ATV-related deaths.
CPSC compiles information on ATV-related deaths from its main injury and death
database files; data sources for these files include medical examiner and coroner reports, death certificates, newspaper
clippings, referrals, and
consumer reports of ATV
crashes ( 1 ). An ATV-related death was defined as a death caused by injury of a driver
or passenger of an ATV that was operated for nonoccupational purposes. To meet the
AP (Associated Press) photo/Amy Sancetta
case definition, the cause of death had to be attributed to the ATV incident rather than
to a preceding event (e.g., myocardial infarction while riding an ATV).
Of the 113 ATV-related deaths in West Virginia during 1985–1997, 100 (88%)
occurred among males (Table 1). Age at de
ath ranged from 18 months to 75 years
(mean age: 29 years for males; 17 years for females); 18 (16%) persons were aged
SAFER
≤12 years, and 11 (10%) were aged
≥55 years.
The immediate cause of two thirds of deaths was trauma to the head or neck. Of the
74 persons who died from head or neck injuries, at least 55 (74%)
were not
wearing
Mandatory
program
helmets at the time of the crash. Information on helmet use was
not available for
Voluntary program
17 (23%) deaths. In the remaining two (3%) deaths, one driver’s helmet cracked when
Planning program
he hit a tree, and in the other case, the driver collided with a truck,
and the impact
program activity
forced the helmet off of his head. Other factors that may haveNocontributed
to ATVrelated deaths included alcohol or drug use (20% of cases),
carr ying passengers
(25%), and excessive speed (10%).
Collisions accounted for the largest proportion (42%) of deaths; the most c
ommon
collisions were with fixed objects (e.g., trees, cable wires, guardrails, and rocks) (32%)
and with other vehicles (10%) (Table 1). ATVs that overturned and landed on riders
accounted for 38% of deaths; overturns occurred in ditches, ravines, embankments,
and on other rough terrain.

Centers for

*ATVs are motorized, gasoline-powered vehicles generally weighing 300–600 lbs, with oversized, low-pressure tires, a seat designed to be straddled by the user, and handlebars for
steering. They are intended for use by riders on off-road,
nonpaved terr ain.
U.S. DEPARTMENT OF HEALTH & HUMAN SERVICES

% positive

Patient 1
On February 23, 1991, a woman from Denver traveled to Rosarito Beach, Mexico,
for 1 day ( 3 ). On March 17, she developed headache and nausea, and on March 23,
became jaundiced. A serum specimen obtained on March 23 demonstrated a serum
aspartate aminotransferase (AST) level of 2100 U/L (normal: 0–35 U/L), an alkaline
phosphatase level of 516 U/L (normal: 110–295 U/L), and a total bi
lir ubin level of
7.5 mg/dL (normal: 0–1 mg/dL). Physical examination was normal except for jaundice.
Tests for serolog ic m arkers for hep atitis A, B, and C were negative, and an ultrasonogram of the liver was normal. Serum samples obtained on April 18 and May 31
were positive for anti-HEV by uorescent antibody (FA) blocking assay (titers of 1:512
and 1:128, respectively) and by a Western blot assay.
The patient had no underlying medical problems and denied excessive alcohol consump tion, injecting-drug use (IDU), blood transfusions, or contact with anyone known
to have hepatitis during the 6 months before onset of her illness. Al
though the source
of infection for this patient was not clearly established, she reported drinking margaritas with crushed ice at two restaurants and eating salsa and chips while in Mexico; she
denied drinking water or eating other uncooked food. The patient recovered fully.
Al though her three traveling companions also consumed margaritas with ice, they
did not become ill, and serum samples from all three were negative for anti-HEV.

health-care services by survivors, the New York City DepartOn September 11, 2001, a jet aircraft crashed into the north
ment of Health (NYCDOH) conducted a field investigation
tower of the World Trade Center (WTC) in lower Manhatto review emergency department (ED) and inpatient medical
tan. Minutes later, a second aircraft crashed into the south
records at the four hospitals closest to the crash site and a fifth
tower. The impact, fires, and subsequent collapse of the buildMorbidity and Mortality Weekly Report
hospital that served as a burn referral center. This report sumings resulted in the deaths of thousands of persons. The premarizes
findings
that assessment, which indicated that the
cise number and causes of deaths could not be assessed inWeekly
the
/ Vol. 60
/ No.of26
July 8, 2011
arrival of injured persons to this sample of hospitals began
immediate aftermath of the attack; however, data were availwithin minutes of the attack and peaked 2 to 3 hours later.
able on the frequency and type of injuries among survivors
Among 790 injured survivors treated within
48 hours,
(Figure 1). In previous disasters, such information assisted in
50
3500
approximately 50%Drug
received Overdose
care within 7 hoursDeaths
of the attack,— Florida, 2003–2009
characterizing type and severity of injuries and the health-care
most for inhalation or ocular injuries; 18% were hospitalized.A (2009 H1N1)
services needed by survivors (1 ). To assess injuries and use of
In the United
States in 2007,
unintentional
poisonings
wereeffectsA (H3)
included only drug-caused deaths, referred to in this report as
3000
Comprehensive
surveillance
of disaster-related
health
the secondis leading
cause
death
(after
motor-vehicle
drug overdose
deaths.
not performed)
40
an integral
partofofinjury
effective
disaster
planning
and response.A (Subtyping
FIGURE 1. A survivor of the World Trade Center attack. Most
B
(1); approximately
of all
unintentional
poisoning rapid
Using U.S. Census resident population estimates, annual
Within 6 hours93%
of the
WTC
attack, a NYCDOH
survivors treated at sampled hospitals had inhalation crashes)
and
assessment
team
began
collectingalso
demographic
clinical% positive
deaths were
caused by
drug
poisoning,
known2500
asand
drug
ocular injuries.
drug overdose death rates per 100,000 population were
dataFrom
on all1990
persons
emergency
care from 8 a.m. calculated for all drugs, prescription drugs, illicit drugs
overdose (2).
to who
2001sought
in Florida,
the nonsuicidal
30
11 to 8 a.m.
September
at the 2000
fiverecent
Manhattan (including specifically heroin and cocaine),
poisoningSeptember
death rate increased
325%
(3). To 13
characterize
opioid analgesics
hospitals.
Information
about
person
included
sex, age, (including specifically methadone, hydrocodone, oxycodone,
trends in drug
overdose
death rates
in each
Florida,
CDC
analyzed
of arrival
at the hospital,
dateCommission.
and time of registration
data frommode
the Florida
Medical
Examiners
This
and morphine), benzodiazepines (including specifically
or
initial
assessment,
type
and
anatomic
location
1500 of injury or
report summarizes the results of that analysis, which found
alprazolam), and ethanol. To test for the20 statistical significance
illness, whether the injury or illness was attributable to the
that, from 2003 to 2009, the number of annual deaths in
of changes in death rates from 2003 to 2009, z-tests were
attack, and whether the person was admitted for additional
which medical
examiner testing showed lethal concentrations
1000
treatment or was discharged from the ED. Among
the 1,688 conducted in categories with annual counts >100, and
No. of positive specimens

occurred in some parts of the world and have generally been related to contaminated
water supplies. Until recently, when research-based serologic tests (
1,2 ) were developed to test for antibody to hepatitis E virus (anti-HEV), no serologic test was available
to identify HEV infection, and diagnosis
depended on a history of exposure in an appropriate epidemiologic setting and the exclusion of other causes of viral hepatitis.
During 1989–1992, acute HEV infection was documented among six persons in the
United States who had returned from international travel. This report summarizes
CDC’s serologic document ation of acute HEV infection—presumed to have been acquired during international travel—in four of these persons.

examination of overlapping confidence intervals from gamma
10
distributions was used with counts <100.
During 2003–2009, a total of 16,550 drug overdose deaths
were recorded by Florida medical examiners. The annual
number of deaths increased 61.0%, from
0 1,804 to 2,905, and
44
46
48
50
52
2
4
6
the death
rate increased 47.5%,
from 10.6 to 15.7 per 100,000
2010
2011
population. In 2009, approximately eight drug overdose
Surveillance week and year
deaths
occurred each day. During 2003–2009, 85.9% of drug
overdose deaths were unintentional, 11.1% were suicides, 2.6%
were of undetermined intent, and 0.4% were homicides or
pending. Prescription medications were implicated in 76.1%

INSIDE
873 Cephalosporin Susceptibility Among Neisseria
gonorrhoeae Isolates — United States, 2000–2010
878 Update to CDC’s U.S. Medical Eligibility Criteria for
Contraceptive Use, 2010: Revised Recommendations
for the Use of Contraceptive Methods
During the Postpartum Period
884 Vital Signs: Colorectal Cancer Screening, Incidence,
and Mortality — United States, 2002–2010
890 Notes from the Field: Botulism Caused by
Consumption of Commercially Produced Potato
Soups Stored Improperly — Ohio and Georgia, 2011
891 QuickStats

U.S. Department of Health and Human Services
Centers for Disease Control and Prevention

U.S. Department of Health and Human Services
Centers for Disease Control and Prevention

Supplement

CONTENTS
Foreword...................................................................................................................1
Introduction.............................................................................................................2
A History of MMWR................................................................................................7
The Cornerstone of Public Health Practice:
Public Health Surveillance, 1961–2011 .................................................... 15

Note to Readers

This supplement includes the individual perspectives of
public health professionals external to CDC. Any opinions
expressed by these contributors are their own rather than
the “voice of CDC.”

Evolution of Epidemic Investigations and Field Epidemiology during
the MMWR Era at CDC — 1961–2011 ....................................................... 22
Laboratory Contributions to Public Health................................................ 27
History of Statistics in Public Health at CDC, 1960–2010:
the Rise of Statistical Evidence .................................................................... 35
Changing Methods of NCHS Surveys: 1960–2010 and Beyond ........ 42
Vaccine-Preventable Diseases, Immunizations,
and MMWR — 1961–2011............................................................................. 49
Control of Health-Care–Associated Infections, 1961–2011 ................ 58
AIDS: the Early Years and CDC’s Response................................................. 64
Fifty Years of Progress in Chronic Disease Epidemiology
and Control ........................................................................................................ 70
Injury Prevention, Violence Prevention, and Trauma Care:
Building the Scientific Base .......................................................................... 78
Environmental Health in MMWR — 1961–2010 ...................................... 86
Occupational Epidemiology and the National Institute for
Occupational Safety and Health ................................................................. 97
Trends in Global Health and CDC’s International Role, 1961–2011...104
Advice to a Modern-Day Rip Van Winkle: Changes in State and Local
Public Health Practice During the MMWR Era at CDC........................112
On the cover: See page 120 for a description of the cover art.
The MMWR series of publications is published by the Office of Surveillance, Epidemiology, and Laboratory Services, Centers for Disease Control and Prevention (CDC),
U.S. Department of Health and Human Services, Atlanta, GA 30333.
Suggested citation: Centers for Disease Control and Prevention. [Article title]. MMWR 2011;60(Suppl):[inclusive page numbers].

Centers for Disease Control and Prevention

Thomas R. Frieden, MD, MPH, Director
Harold W. Jaffe, MD, MA, Associate Director for Science
James W. Stephens, PhD, Office of the Associate Director for Science
Stephen B. Thacker, MD, MSc, Deputy Director for Surveillance, Epidemiology, and Laboratory Services
Stephanie Zaza, MD, MPH, Director, Epidemiology and Analysis Program Office

MMWR Editorial and Production Staff
Ronald L. Moolenaar, MD, MPH, Editor, MMWR Series
Christine G. Casey, MD, Deputy Editor, MMWR Series
Teresa F. Rutledge, Managing Editor, MMWR Series
David C. Johnson, Lead Technical Writer-Editor
Karen L. Foster, MA, Project Editor
Frederic E. Shaw, MD, JD, Katrin S. Kohl, MD, PhD,
Lisa M. Lee, PhD, MS, Stephen B. Thacker, MD, MSc
Guest Editors

Martha F. Boyd, Lead Visual Information Specialist
Maureen A. Leahy, Julia C. Martinroe,
Stephen R. Spriggs, Terraye M. Starr
Visual Information Specialists
Quang M. Doan, MBA, Phyllis H. King
Information Technology Specialists

MMWR Editorial Board

William L. Roper, MD, MPH, Chapel Hill, NC, Chairman
Virginia A. Caine, MD, Indianapolis, IN
Patricia Quinlisk, MD, MPH, Des Moines, IA
Jonathan E. Fielding, MD, MPH, MBA, Los Angeles, CA
Patrick L. Remington, MD, MPH, Madison, WI
David W. Fleming, MD, Seattle, WA
Barbara K. Rimer, DrPH, Chapel Hill, NC
William E. Halperin, MD, DrPH, MPH, Newark, NJ
John V. Rullan, MD, MPH, San Juan, PR
King K. Holmes, MD, PhD, Seattle, WA
William Schaffner, MD, Nashville, TN
Deborah Holtzman, PhD, Atlanta, GA
Anne Schuchat, MD, Atlanta, GA
John K. Iglehart, Bethesda, MD
Dixie E. Snider, MD, MPH, Atlanta, GA
Dennis G. Maki, MD, Madison, WI
John W. Ward, MD, Atlanta, GA

Supplement

Foreword
Alexander Langmuir became the first Chief Epidemiologist
at CDC (then called the Communicable Disease Center) in
1949. One of his many enduring contributions to the agency
and to public health was to engineer the transfer in 1961 of
the Morbidity and Mortality Weekly Report (MMWR) from its
former home at the National Office of Vital Statistics to CDC.
This supplement to MMWR celebrates the anniversary of its
arrival at CDC and the 50‐year contribution it has made to
CDC and public health. Langmuir had the foresight to envision the revitalization of the decades‐old publication, not only
to enable CDC to share its work with the nation, but also to
influence the practice and impact of public health throughout
the world. This supplement celebrates MMWR through perspectives on how public health has changed during the past 50
years. Articles in this issue reflect on how the focus of public
health has expanded from communicable disease to also include
a broad array of acute and chronic public health challenges.
Langmuir had a powerful ability to visualize the future but
an even more powerful ability to realize his vision through the
force of his strong will and his flair for recruiting and mentoring young men and women in public health. MMWR was
part of his vision, and as its unofficial editor for many years,
he demanded high‐quality science presented in clear and crisp
prose—qualities that have endured to the present day.
Like so many of Langmuir’s innovations, MMWR has
evolved with the years but it has always remained vital to each
new challenge. As CDC’s flagship publication, MMWR documents the impact of public health programs throughout the
United States and the world, and in many cases acts as a catalyst
for improvement. When health departments or ministries seek
CDC’s scientific information, often driven by urgent threats to
the public’s health, they seek out MMWR for its clearly crafted
scientific articles and reliable clinical and public health recommendations based on the best available science.
In Langmuir’s day, issuing a weekly scientific publication was
unusual, if not unprecedented, at a federal agency. Langmuir
could not have envisioned that his MMWR would one day be
available 24 hours a day, 7 days a week on computers, cell phones,
and portable electronic devices of all kinds. Today MMWR is
distributed worldwide through both print and electronic media
and employs the latest communications technologies, including
the Internet, e‐mail, social media, and podcasts. As new methods
of communication evolve, so will MMWR.
Surveillance and epidemiology have always been the cornerstones of public health. The MMWR series has provided a mechanism to communicate data from national and international
surveillance systems, as well as from epidemiologic, statistical,
and laboratory research. During the past 2 decades, terrorism

and emergency response, modernization and globalization of
the food supply, and a wide range of environmental health
threats have dramatically affected public health practice—and
these stories have all been carefully told in the pages of MMWR.
Many of the most important communicable disease events
during the past 50 years have been marked by articles in
MMWR. Examples include the discovery of the bacterial cause
of Legionnaires disease in 1977; the initial reports linking Reye
syndrome to salicylates in 1980; the first five published cases
of AIDS in 1981; the first report of iatrogenic HIV transmission in 1990; the first case reports of the intentional release of
anthrax spores in 2001; the first reports of severe acute respiratory syndrome (SARS) in 2003; and the first two reports of
2009 pandemic influenza A (H1N1) .
Even in its early days at CDC, MMWR published many
reports on noninfectious diseases, such as pentachlorophenol
poisoning in newborn infants in 1967; lead absorption in
1973; angiosarcoma of the liver among workers exposed to
polyvinyl chloride in 1974; and acute childhood leukemia in
1976. In recent years, MMWR has published more reports on
noninfectious diseases, injuries, chronic diseases, and related
behaviors (e.g., arthritis, autism spectrum disorder, depression, infant maltreatment, sleep deprivation, and excessive
television viewing), and many reports on the leading causes
of death: cardiovascular disease, smoking, stroke, obesity, and
harmful alcohol use.
In recent decades, behavioral and social science, economics, informatics, and genomics increasingly have contributed
to public health, and reports of these have appeared with
increasing regularity in MMWR. Public health events such as
contamination of commercial food products, threats to patient
safety in health‐care settings, and natural disasters (e.g., the
recent floods in the Midwest, heat waves in the Northeast, the
earthquake in Haiti, and flooding in Pakistan) will continue
to challenge the health infrastructure. In addition, health
reform and the coalescence of clinical medicine, veterinary
medicine, and public health are creating new opportunities
for promoting prevention as the defining concept in improving the health of the public. Innovations such as electronic
health records are providing unique opportunities to better
understand and improve health care and health status. Through
all these changes, MMWR will continue reporting on urgent,
emerging, and routine public health findings, thereby helping
CDC monitor and protect the public’s health at home and
around the world, and will remain an essential tool for CDC’s
far‐ranging mission.
Thomas R. Frieden, MD
Director, CDC
MMWR  /  October 7, 2011  /  Vol. 60

1

Supplement

Introduction
Frederic E. Shaw, MD, JD1*
Katrin S. Kohl, MD, PhD2
Lisa M. Lee, PhD1
Stephen B. Thacker, MD1
1Office of Surveillance, Epidemiology and Laboratory Services, CDC, Atlanta, Georgia.
2Division of Global Migration and Quarantine, National Center for Emerging and Zoonotic Infectious Diseases, CDC, Atlanta, Georgia.

This supplement of MMWR celebrates the 50th anniversary
of CDC’s first publication of MMWR on January 13, 1961
(Figure 1). MMWR was not new in 1961, but it was new to
CDC, an agency that itself had been founded only 15 years
earlier, in 1946 (1). The longer history of MMWR traces back
to July 13, 1878, when the first predecessor of MMWR, called
simply The Bulletin of the Public Health, was inaugurated. The
Bulletin was established in accordance with the first National
Quarantine Act, passed by Congress 2 months earlier. The
Act ordered the Surgeon General of the U.S. Marine-Hospital
Service to begin publishing abstracted disease reports collected
from U.S. consuls in foreign lands to alert U.S. quarantine
officials about what diseases could be expected among passengers arriving on steamships (2,3). In the 83 years from 1878
to 1961, MMWR went through several incarnations. By 1952,
the publication had its current name and was being published
by the National Office of Vital Statistics, an agency within
the U.S. Department of Health, Education and Welfare. In
1960, CDC’s renowned chief of epidemiology, Alexander D.
Langmuir, decided that MMWR should be transferred to CDC
(then known as the Communicable Disease Center). After
much discussion, and as Langmuir later said in an interview,
“all sorts of pulling out teeth by the roots without anesthesia
and all kinds of internal frictions,” in 1960, MMWR was
transferred to CDC (4).
In 2009, as the 50th anniversary of MMWR loomed, the
MMWR Editor (F.E.S.) began discussions with leaders at CDC
and the MMWR Editorial Board about how best to commemorate this date. Members of the Board, editors, and friends of
MMWR offered many good ideas. In the end, the most persuasive idea was to celebrate the 50th anniversary simply by doing
what MMWR has done best for 5 decades at CDC: publish
articles of high value to its readers. The title of the supplement is
“Public Health Then and Now: Celebrating 50 Years of MMWR
at CDC.” The supplement’s guest editors (F.E.S., K.S.K., L.M.L.,
S.B.T.) selected a cadre of expert authors who have long experience in their respective fields of public health—enough to
enable them to look back over the past 50 years and trace the
most important influences and developments. The guest editors
asked the authors to answer three key questions. What was the
* Editor, MMWR, 2007–2010.

2

MMWR  /  October 7, 2011  /  Vol. 60

state of the art in 1961? How did it develop through 50 years
into its present form? What does the future hold? Thus, with few
exceptions, the 16 articles that make up this supplement are not
meant to be about MMWR but instead are meant to trace the
development of key areas of public health through the 50-year
era of MMWR at CDC.
The authors took up the challenge admirably. The result is
a diverse set of articles that portray public health in 1961 and
forward in time to the present and beyond. The articles range
from detailed historical review, to analyses of MMWR content,
to the more whimsical. They are not meant to be exhaustive,
nor can they treat their topics as thoroughly as would a longer
text, but they do depict the main events, developments, and
innovations that led public health to where it stands today.

What is MMWR?
In 1996, on the occasion of the 50th anniversary of CDC,
three long-serving editors of MMWR restated the purpose of
the publication: “…to report events of public health interest
and importance to CDC’s major constituents—state and
local health departments—and as quickly as possible”, and
to distribute “… objective scientific information, albeit often
preliminary, to the public at large” (5). Although the content of
MMWR has changed since its inception in 1878, by and large it
has included three basic elements: 1) short reports about acute
public health events, such as outbreaks of infectious diseases,
environmental events, clusters of noninfectious diseases, and
analyses on the incidence and prevalence of chronic diseases,
conditions, or related behaviors; 2) longer reports and supplements on public health surveillance, policy recommendations,
and special topics; and 3) statistical tables on the week’s morbidity and mortality in the United States, with a wrap-up report
published after the end of the surveillance year. Over the years,
these elements have changed in scope, complexity, length, and
other attributes, but they remain the core of MMWR’s content.
MMWR has been the first source of information for many
important public health events. Perhaps the best known is an
MMWR report titled “Pneumocystis pneumonia—Los Angeles,”
which was published on June 5, 1981 (6). It described five
cases of an immunosuppressive illness in previously healthy

Supplement

FIGURE 1. Facsimile of the first issue of MMWR published at CDC,
January 13, 1961

men who had had sex with men that later became known as
acquired immunodeficiency syndrome (AIDS). Many other
examples exist of first reports in MMWR. To name just a few
examples: in 1970, MMWR reported on a nationwide epidemic
of bacteremia associated with contaminated intravenous fluids
(7); in 1976, on the occurrence of Guillain-Barré syndrome
associated with the swine influenza vaccine (8); in 1977, on the
discovery of the organism that causes Legionnaires disease (9);
in 1991, on the effectiveness of folic acid for the prevention
of spina bifida (10); in 1993, on an outbreak of hantavirus
pulmonary syndrome (11); and two years ago, on the first
two cases of 2009 pandemic influenza A (H1N1) (12). The
traditional function of these first reports has been to fill the
scientific information gap between immediate public health
notifications through the news media and later publication of
full-length articles in the peer-reviewed medical literature (2).
From 1961 to 1985, MMWR consisted only of the weekly
publication, usually an eight- to 16-page booklet containing
a few short narrative reports and the weekly morbidity and
mortality tables, and the annual Summary of Notifiable Diseases.
Since 1985, MMWR has evolved into the MMWR Series, a
collection of six different products: 1) the MMWR weekly, 2)

the annual Summary of Notifiable Diseases, 3) CDC Surveillance
Summaries, 4) Recommendations and Reports, 5) special supplements, and 6) the MMWR weekly podcasts.
Although the general public best recognizes MMWR by the
weekly report and the podcasts, the public health community
relies heavily on the other components of the series. The CDC
Surveillance Summaries, for example, a series of long-form
reports and tables split off from the weekly in 1985 to publish
the results of public health surveillance, often represent the
only source of published surveillance statistics for certain topic
areas. A few examples of recent reports include a report on the
prevalence of autism spectrum disorders (13), an annual report
on malaria surveillance (14), and a report on out-of-hospital
cardiac arrests (15). The Recommendations and Reports series,
split off from the MMWR weekly in 1990, consists of official
recommendations from CDC. Many of these reports come from
the Advisory Committee on Immunization Practices (ACIP)
and present official recommendations for the use of childhood
and adult vaccines. Recent examples of Recommendations and
Reports topics include field triage of injured patients (16),
guidelines for diagnosing and treating opportunistic infections
in AIDS patients (17,18), and ACIP’s guidelines for treatment
and chemoprophylaxis of influenza (19). The MMWR podcast
series began in 2006 and consists of two weekly podcasts: A
Cup of Health with CDC, a 5- to 7-minute podcast, and A
Minute of Health with CDC, a 59-second podcast.† Unlike the
other five MMWR series, which are aimed at state and local
health departments and other health professional audiences,
the podcasts are aimed at a consumer audience.
Throughout its history one of MMWR’s core functions has
been to report routine weekly surveillance statistics. Various
forms of statistical tables on mortality and, beginning early in
the 20th century, on morbidity, have appeared in MMWR since
its inception as the Bulletin in 1878. For 39 years, the journal
Public Health Reports, of which MMWR was then a part, carried
the following motto above its surveillance tables: “No health
department, State or local, can effectively prevent or control
disease without knowledge of when, where, and under what
conditions cases are occurring.” By the time Langmuir brought
MMWR to the Communicable Disease Center in 1961, he
understood that surveillance data collected but never disseminated are of no use, and this understanding has remained part
of MMWR’s central function (20).
The current MMWR weekly contains three morbidity and
mortality tables plus a table published quarterly about tuberculosis. Table I lists provisional case counts for 40 infrequently
reported nationally notifiable diseases (i.e., those for which
<1,000 cases were reported during the preceding year). For
† See

http://www.cdc.gov/mmwr/mmwrpodcasts.html.

MMWR  /  October 7, 2011  /  Vol. 60

3

Supplement

example, for the week ending May 14, 2011, the 19th surveillance week for 2011, the table showed 19 cases of measles for
the reporting week, 7 cases of noncholera Vibrio species infections, and five or fewer cases for all the other listed diseases.
Table II lists provisional cases for >20 other selected nationally notifiable diseases for the current week, the median and
maximum cases reported over the previous 52 weeks, and the
cumulative (year-to-date) count of cases for the current and
previous year. The diseases are listed by region and state, plus
the District of Columbia, and five U.S. territories. During the
19th surveillance week of 2011, for example, Table II showed
that 147 cases of giardiasis had been reported in the United
States, including 23 from California, and that 19 cases of
hepatitis A had been reported, including three from Georgia.
Table III is a mortality table for 122 U.S. cities. It lists the
weekly number of deaths that occurred in the reporting jurisdiction by age group and has a separate column for deaths
attributed to pneumonia and influenza. Since the earliest
precursors of MMWR, mortality data for major U.S. cities
based on death certificates have been reported directly to public
health authorities and published in some form of this table.
Table III is the nation’s only national listing of weekly deaths.
Detailed information about deaths by place of residence of the
decedent eventually are validated and aggregated into a death
file by CDC’s National Center for Health Statistics, but the
process can take up to 2 years. In a recent issue of MMWR,
Table III showed that, during the week ending May 14, 2011,
a total of 11,300 deaths were reported from the 122 cities. In
Boston, for example, 133 deaths were reported, 86 of them in
persons aged ≥65 years. Finally, Table IV reports provisional
cases of tuberculosis for the current quarter, the minimum and
maximum of the previous 4 quarters, the year to date, and the
previous year’s year to date in each U.S. region, state, and territory, as well as New York City and the District of Columbia.
In 1961, Langmuir made clear that MMWR’s primary audience would be state and local health departments (20). Langmuir
intended MMWR to be CDC’s main method of mass communication with these departments and with the public health
community. By the early 1980s, CDC was mailing MMWR
free of cost to approximately 120,000 subscribers. In 1982,
because of federal budget cuts, CDC was forced to reduce free
circulation, but the gap was filled in 1983 by the Journal of the
American Medical Association (JAMA), which began reprinting
selected MMWR articles in its pages (21), a practice that continues today. In addition, beginning in 1983, the Massachusetts
Medical Society began reprinting MMWR to paid subscribers
(22),§ another practice that continues today. MMWR began
electronic circulation in 1995 (23), and over time, electronic
§ For

4

a time, MMWR also was reprinted by the Ochsner Clinic.

MMWR  /  October 7, 2011  /  Vol. 60

subscription has increased to approximately 100,000. CDC
still prints several thousand paper copies of MMWR and sends
these free to state and local health departments, members of
the news media, libraries, and a few other categories. Together
with the circulation at the Massachusetts Medical Society and
the U.S. government’s Superintendent of Documents, the total
print and electronic circulation of MMWR is now 134,000 as
of September 2011; however, this number does not begin to
capture MMWR readers in JAMA and other publications and
approximately 1 million visitors to the MMWR website monthly.
In addition, the MMWR podcasts are downloaded by about
50,000 listeners per week.
Langmuir knew that MMWR would be of great interest to
the news media. Since the 1970s, CDC has given reporters
access to MMWR articles the day before the articles are published. Today, reporters receive an advance copy of MMWR
on Wednesday evenings, write their stories over Wednesday
night, and then publish them after the MMWR media embargo
ends at Thursday noon. For 5 decades, most health reports
attributed to CDC in the news media likely have originated
in MMWR. Even today, when viewers of evening television
see something that “CDC reported today,” often the MMWR
logo is visible in the graphics. MMWR remains a main source
of scientific information emanating from CDC, even though
other channels, such as informal posting of information on
the Web or releases given directly to news organizations, have
begun to play a greater role.
Beginning in 2004, MMWR began releasing urgent reports
outside the routine weekly MMWR issue. These reports, called
“Early Releases” (formerly “Dispatches”), are sent immediately
to electronic subscribers. MMWR uses Early Releases when the
urgency of the public health problem cannot wait for the issuance
of the weekly MMWR on Thursday noon. In 2010, CDC began
a new monthly communication initiative called “CDC Vital
Signs,” which is anchored by a scientific report in MMWR (24).

MMWR and Medical Journals
Langmuir sometimes referred to his beloved MMWR as a
“medical journal.” In a 1979 interview, for example, Langmuir
boasted that MMWR’s circulation of 84,000 qualified it as “one
of the largest medical journals in the world” (4). However,
MMWR has always carefully differentiated itself from medical
journals. Even though some of the narrative articles in MMWR
have the look and feel of articles in medical journals, MMWR
remains distinct from medical journals—indeed from all other
health-related publications.
The most obvious differences lie in the long-form CDC
Surveillance Summaries and Recommendations and Reports

Supplement

series. The CDC Surveillance Summaries represent the federal
government and state health departments reporting official
comprehensive surveillance statistics, a function not within
the purview of medical journals. Similarly, Recommendations
and Reports contains official federal public health recommendations, also outside the scope of most medical journals.
Several other differences exist. A major one is that, unlike
medical journals (with a few exceptions, i.e., certain special
supplements such as this one), the content published in
MMWR constitutes the official voice of its parent, CDC. One
sign of this is the absence in MMWR of any official disclaimers.
Although most articles that appear in MMWR are not “peerreviewed” in the way that submissions to medical journals are,
to ensure that the content of MMWR comports with CDC
policy, every submission to MMWR undergoes a rigorous
multilevel clearance process before publication. This includes
review by the CDC Director or designate, top scientific directors at all CDC organizational levels, and an exacting review by
MMWR editors. Articles submitted to MMWR from non-CDC
authors undergo the same kind of review by subject-matter
experts within CDC. By the time a report appears in MMWR,
it reflects, or is consistent with, CDC policy.
For decades, articles in the MMWR weekly written by CDC
scientists bore attribution only to the CDC program in which
the scientist worked (state or local health department authors
were always attributed by name). The intent was to convey
to readers that the author of the article was actually CDC as
an institution, not the individual contributors. In 2002, the
MMWR weekly began allowing attribution to individual CDC
contributors by name, but even today, reports in the weekly still
are attributed to CDC officially as an institution and appear
as authored by CDC in the National Library of Medicine’s
MEDLINE database.
Another identifying characteristic of MMWR is its unique
format. In its early years, MMWR established its trademark short
rapid report format for breaking public health problems. In a
1984 memorandum, an MMWR editor described the publication’s style as having “few adjectives and verbs.” During the
same year, an observer described MMWR’s style as “brisk and
businesslike, redolent of competence and devoid of levity….
A crisp, lucid, oddly vivid style suggestive of Hemingway as
retold by Strunk and White” (25). Although a few reports in
today’s MMWR are perhaps more ornate than those of previous
decades, the publication still works hard to retain its short form
and almost quirky devotion to careful, precise Spartan language.
Yet another difference between MMWR and most medical journals is its absence of correspondence from readers,
advertising, advocacy, and opinion. Most medical journals are
part of a conversation with their readers through publication
of letters to the editor and responses from authors. MMWR

has always accepted letters (now e-mails) from readers and
has forwarded these to authors for individual response but
has never published correspondence and has left the forums
for public health discussion to other publications.¶ MMWR
contains no advertising or promotional materials, even on
behalf of CDC, or any advocacy or self-promotion for CDC
or for particular public health programs. Although since the
late 1960s MMWR has published an “editorial note” for most
articles appearing in the weekly (little known fact: these are
written by the contributors or the CDC subject-matter experts,
not by the MMWR editor), in keeping with its status as the
official voice of CDC, MMWR has never published “opinion”
per se. Comments in editorial notes all are in accordance with
CDC policy, and no individual opinion appears.
MMWR’s continued adherence to an unadorned matter-offact style might be part of the reason it has maintained a high
level of credibility among its readers. In a survey conducted by
Mercer Management Consulting during 2005–2006 among
>11,000 subscribers, MMWR’s score on credibility was 4.76
of 5.00 (1 = poor, 5 = excellent). In the same survey, MMWR
scored an average respondent score of 4.60 of 5.00 on quality
of content, 4.52 on usefulness, 4.49 on timeliness, and 4.40 on
readability. Of 18 publications tested, no publication outscored
MMWR on credibility, usefulness, or quality of content. Besides
its simple style and lack of advertising, another reason for these
high reader marks likely is MMWR’s association with CDC.

MMWR in the Future
When public health threats arise, one of MMWR’s most
important traditional functions has been to provide crucial
scientific information during that time between the immediate
notification to the public about the threat and the later definitive scientific description of the event in a medical journal (2).
This important “filling the gap” function has remained a main
part of MMWR’s mission. As a classic example, on February 1,
2008, MMWR published an Early Release report about acute
allergic-type reactions among patients undergoing hemodialysis in multiple states (26). The authors said the temporal and
geographic distribution of these reactions suggested common
exposure to a widely distributed health-care product. They
named heparin as a possible culprit and asked readers to send
reports to their local or state health department. By February
11, heparin had been identified as the most likely culprit, and
the manufacturer had halted production. A definitive scientific
¶ In 2010, MMWR established a Facebook page on which readers can comment

on MMWR articles; so far, this page has been used almost entirely by lay readers
rather than by MMWR’s scientific audience.

MMWR  /  October 7, 2011  /  Vol. 60

5

Supplement

description of the incident appeared in the New England
Journal of Medicine on June 5, 2008 (27).
In the Internet age, the information gap between immediate
announcement of public health events by the news media and
publication in medical journals is narrowing. MMWR’s “filling
the gap” function can be done now in several ways. During the
recent pandemic of 2009 influenza A (H1N1), CDC programs
relied heavily on publication in MMWR, and 45 reports on
the pandemic appeared in its pages through the end of 2010.
However, to an unprecedented degree, CDC also relied on
informal postings on the Web and direct releases to the media to
convey a large amount of scientific information to health departments and the public. In addition, medical journals were much
quicker about publishing fresh results. Soon after the outbreak
was recognized, the New England Journal of Medicine published
information about the epidemiology of the newly characterized
disease within just a few days after data collection (28). Many
other publications posted electronic journal articles within just
days of submission. In addition, other informal methods of
communication have come to the fore (e.g., PLoS Currents).
In the last few years, the Internet has revolutionized medical
publishing. Old medical journals are now questioning their
business models, especially models that rely on printing on
paper. The extent to which this publishing maelstrom will
affect MMWR is uncertain. Certainly, some of the scientific
functions of MMWR cannot be supplanted by informal posting on the Web. CDC Surveillance Summaries and vaccine
recommendations must maintain a minimum level of formality
to be considered credible and generally that includes formal
indexing in MEDLINE, a step that makes them part of the
medical literature. That need suggests they will be published
in MMWR for a long time to come, but even that is uncertain.
Already, some traditional MMWR contributors, faced with
pressure to publish material more quickly and less expensively,
have elected to simply post materials on the Web rather than
submit them for formal editing, publication, and indexing.
Over the past 50 years, MMWR has changed as CDC’s
mission has changed and as successive generations of MMWR
authors, editors and staff members have carried it forward. One
tribute to MMWR’s continued vitality is the growing desire of
many other nations to have their own MMWR-like publications, and MMWR editors often give advice on this to foreign
ministries of health. Many people—readers, staff members,
and friends—have come to love the little publication that has
done so much for public health over so long, and they now
worry about its fate in the modern-day publishing maelstrom.
Perhaps all should recall the many times in the past 50 years
when upheavals in public health, technology, and publishing
seemed to spell trouble for MMWR, but through it all, MMWR
adapted, persevered, and flourished.
6

MMWR  /  October 7, 2011  /  Vol. 60

References
1. Etheridge EW. Sentinel for health: a history of the Centers for Disease
Control. Berkeley: University of California Press; 1992.
2. Gregg MB. From morbidity and mortality to prevention and control.
Presentation to the American Medical Writers Association, Atlanta,
Georgia, September 30, 1980.
3. Hunter JS. Public Health Reports’ first century — a chronicle. Public
Health Rep 1978;93:591–9.
4. Langmuir AD. Interview [videotape]. Menlo Park, CA: Alpha Omega
Alpha Honor Medical Society; 1979.
5. CDC. Preface. Highlights in public health: landmark articles from the
MMWR, 1961–1996. MMWR 1999 [unnumbered suppl]:v–vi.
Available at http://www.cdc.gov/mmwr/pdf/other/highlite.pdf.
6. CDC. Pneumocystis pneumonia—Los Angeles. MMWR 1981;30:250 –2.
7. CDC. Nosocomial bacteremias associated with intravenous fluid
therapy—USA. MMWR 1971 (March 6);20 (special suppl).
8. CDC. Guillain-Barré syndrome—United States. MMWR 1976;25:401.
9. CDC. Follow-up on respiratory illness—Philadelphia. MMWR
1977;26:9–11.
10. CDC. Use of folic acid for prevention of spina bifida and other neural
tube defects, 1983–1991. MMWR 1991;40:513–6.
11. CDC. Outbreak of acute illness—southwestern United States, 1993.
MMWR 1993;42:421–4.
12. CDC. Swine influenza A (H1N1) infection in two children—southern
California, March–April 2009. MMWR 2009;58:400–2.
13. CDC. Prevalence of autism spectrum disorders—Autism and
Developmental Disabilities Monitoring Network, United States, 2006.
MMWR 2009;58(No. SS-10).
14. CDC. Malaria surveillance—United States, 2009. MMWR 2011;60​
(No. SS-3).
15. CDC. Out-of-hospital cardiac arrest surveillance—Cardiac Arrest
Registry to Enhance Survival (CARES), United States, October 1,
2005–December 31, 2010. MMWR 2011;60(No. SS-8).
16. CDC. Guidelines for field triage of injured patients: Recommendations
of the National Expert Panel on Field Triage. MMWR 2009;58(No. RR-1).
17. CDC. Guidelines for the prevention and treatment of opportunistic
infections among HIV-exposed and HIV-infected children. MMWR
2009;58(No. RR-11).
18. CDC. Guidelines for the prevention and treatment of opportunistic
infections among HIV- infected adults and adolescents. MMWR
2009;58(No. RR-4).
19. CDC. Antiviral agents for the treatment and chemoprophylaxis of
influenza—recommendations of the Advisory Committee on
Immunization Practices (ACIP). MMWR 2011;60(No. RR-1).
20. Thacker SB, Gregg MB. Implementing the concepts of William Farr:
the contributions of Alexander D. Langmuir to public health surveillance
and communications. Am J Epidemiol 1996;144(suppl):S23–8.
21. Lundberg GD. Getting the information out faster and some good news
about MMWR. JAMA 1983;249:1483.
22. Relman AS. New distribution of Morbidity and Mortality Weekly
Report. N Engl J Med 1983;308:452.
23. CDC. Availability of electronic MMWR on Internet. MMWR
1995;44:48–50.
24. CDC. Vital Signs: colorectal cancer screening among adults aged 50–75
years—United States, 2008. MMWR 2010;59:808–12.
25. Murphy C. Misfortune’s catalogue. The Atlantic 1984(February):14 –20.
26. CDC. Acute allergic-type reactions among patients undergoing
hemodialysis—multiple states, 2007–2008. MMWR 2008;57:124–5.
27. Kishimoto TK, Viswanathan K, Ganguly T, et al. Contaminated heparin
associated with adverse clinical events and activation of the contact
system. N Engl J Med 2008;358:2457–67.
28. Novel Swine-Origin Influenza A (H1N1) Virus Investigation Team,
Dawood FS, Jain S, et al. Emergence of a novel swine-origin influenza
A (H1N1) virus in humans. N Engl J Med 2009;360:2605–15.

Supplement

A History of MMWR
Frederic E. Shaw, MD, JD1
Richard A. Goodman, MD, JD2
Mary Lou Lindegren, MD3
John W. Ward, MD4
1Public Health Surveillance Program Office, Office of Surveillance, Epidemiology and Laboratory Services, CDC, Atlanta, Georgia
2National Center for Chronic Disease Prevention and Health Promotion, CDC, Atlanta, Georgia
3Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, Tennessee
4Division of Viral Hepatitis, National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention, CDC, Atlanta, Georgia
Corresponding author: Frederic E. Shaw, MD, JD, Public Health Surveillance Program Office, Office of Epidemiology, Surveillance and Laboratory Services,
CDC, Mailstop E-97, 1600 Clifton Road, N.E., Atlanta, GA 30333;Telephone: 404-498-6364; Fax: 404-498-0585; E-mail: [email protected].

MMWR was established to disseminate the results of public health surveillance and owes much of its existence to the
founder of modern surveillance, William Farr (1807–1883).
In 1878, under the sway of Farr, Lemuel Shattuck, and other
pioneers of surveillance, the U.S. government created the first
precursor of MMWR and entered the business of publishing
surveillance statistics. Farr’s influence touched MMWR again
in 1961 when one of his adherents, Alexander D. Langmuir
(Figure 1), brought MMWR to Atlanta and CDC from a federal
office in Washington, D.C. (1). Since its beginnings, MMWR
has played a unique role in addressing emerging public health
problems by working with state and local health departments
to announce problems even before their cause is known,
rapidly disseminating new knowledge about them weeks or
months before articles appear in the medical literature, and
publishing recommendations for their control and prevention.
MMWR has played this role time after time—the discovery
of Legionnaires disease in the 1970s, AIDS and toxic-shock
syndrome in the 1980s, hantavirus pulmonary syndrome in
the 1990s, and severe acute respiratory syndrome (SARS) in
the 2000s. At the same time, MMWR also has reported on
nearly all the major noninfectious public health problems of the
day—environmental emergencies, chronic diseases, injuries,
and new public health technologies. To a great extent, the history of MMWR is the history of disease and injury prevention
and control in the United States (Table 1).

MMWR’s Precursors
MMWR’s history began on April 29, 1878, when Congress
passed the National Quarantine Act. The Act required the
Surgeon General of the U.S. Marine-Hospital Service (later
to become the U.S. Public Health Service [PHS]) to collect
reports from U.S. consular officers on the sanitary condition
of vessels departing for the United States and to give notice
of these vessels to federal and state officers through weekly
abstracts (2). This mandate resulted in The Bulletin of the

Public Health (Figure 2), the first precursor of MMWR. The
Marine-Hospital Service published the first issue of the Bulletin
on July 13, 1878. It ran just six paragraphs and described cases
of cholera, smallpox, and yellow fever in Key West, Florida;
Cuba; and Malta (3). In 1878, a great yellow fever epidemic was
raging in the Mississippi Valley, eventually to claim 20,000 lives
(4), and a reader of these early reports can feel its deadly effects.
On August 24, 1878, the Bulletin published a telegram from
Dr. Booth, the Marine-Hospital Service officer at Vicksburg,
Mississippi: “I am sick; impossible to procure accurate data.”
A week later, the Bulletin’s report from Vicksburg said, “Dr.
Booth, in charge of the patients of the Marine-Hospital Service,
died the 27th.”
On June 2, 1879, Congress repealed the earlier reporting
provisions, and the Bulletin ended after just 46 issues, leaving
dormant the reporting of surveillance statistics by the federal
government. It reawakened with the advent of a new publication in 1887, The Weekly Abstract of Sanitary Reports, which
continued the numbering of the Bulletin. Issue number 47
appeared on January 20, 1887. Like the Bulletin, the new
publication contained communicable disease reports from
foreign ports and the U.S. states, including a mortality table
of U.S. cities. The Weekly Abstract also contained occasional
narrative reports on public health topics. It reached 1,800 readers and was, in its editor’s words, “greatly appreciated not only
by quarantine officers, but steamship companies, merchants,
and the press” (4).
On January 3, 1896, The Weekly Abstract became Public
Health Reports, a journal that is still published today as the
official journal of PHS. Initially, Public Health Reports looked
a great deal like the Weekly Abstract, but in time Public Health
Reports took the form of a full-fledged scientific journal and
published important observations and research on communicable diseases and epidemiologic and laboratory investigations,
plus such items as municipal ordinances, state legislation, and
public health legal opinions. The PHS published Public Health
Reports weekly until 1952, when it became a monthly publication, and in 1974, a bimonthly. By 1913, a motto of public
MMWR  /  October 7, 2011  /  Vol. 60

7

Supplement

FIGURE 1. Alexander D. Langmuir, circa 1965

health surveillance principles was appearing on the masthead
of the publication’s pages reporting notifiable diseases: “No
health department, State or local, can effectively prevent or
control disease without knowledge of when, where, and under
what conditions cases are occurring.” This motto appeared in
Public Health Reports for 39 years (5).
Until 1942, morbidity statistics were collected, compiled,
and published in Public Health Reports by the PHS Division of
Sanitary Reports and Statistics. In that year, this responsibility
was transferred to the Division of Public Health Methods, and
in 1949, to the National Office of Vital Statistics (NOVS),*
another PHS agency (5). Morbidity and mortality statistics
continued to be published in Public Health Reports until
January 20, 1950, when they were transferred to a new NOVS
publication called the Weekly Morbidity Report, the first publication to look like the modern-day MMWR. In 1952, NOVS
changed the name of this publication to the Morbidity and
Mortality Weekly Report.
* NOVS was merged with the National Health Survey in 1960 to form the
National Center for Health Statistics, which became part of CDC in 1987.

Photo: CDC

TABLE 1. Timeline of major events in MMWR history, 1878–2011
Year

Major Event

1878
1887
1896

First issue of The Bulletin of the Public Health, the first ancestor of MMWR, is published. It ceases publication after just 46 weekly issues.
The first Weekly Abstract of the Sanitary Reports is published.
The Weekly Abstract of Sanitary Reports becomes Public Health Reports, the official journal of the U.S. Public Health Service published today by the
Association of Schools of Public Health.
Dissemination of federal morbidity and mortality statistics is transferred from Public Health Reports to the Weekly Morbidity Report, a new publication of
the federal National Office of Vital Statistics (NOVS).
NOVS changes the name of the Weekly Morbidity Report to the Morbidity and Mortality Weekly Report (MMWR).
The Department of Health, Education and Welfare transfers responsibility for publishing the MMWR to the Communicable Disease Center (CDC).
CDC publishes its first issue of MMWR.
CDC’s name is changed to the National Communicable Disease Center.
CDC’s name is changed to the Center for Disease Control.
In January 1977, MMWR publishes its first and only special edition until 2002. It describes the discovery of the organism that causes Legionnaires disease.
CDC’s name is changed to the Centers for Disease Control.
In MMWR, CDC publishes reports of the first five cases of AIDS.
MMWR articles are for the first time included in Index Medicus.
MMWR subscribers are reduced from approximately 120,000 to 12,000 because of federal budget cuts. The Massachusetts Medical Society begins print
subscriptions for MMWR. The Journal of the American Medical Association reprints MMWR articles. Both arrangements continue today.
CDC Surveillance Summaries, a new series of MMWR, is published for the first time.
Recommendations and Reports, a new series of MMWR, is published for the first time.
CDC’s name is changed to the Centers for Disease Control and Prevention.
MMWR content becomes available on an FTP server on the Internet.
MMWR content becomes available on the World-Wide Web.
MMWR format changes from 6-inch by 8-inch, one-color format to 8½ inch by 11 inch, two-color format.
MMWR establishes ability to publish Dispatches, online reports that can be distributed by email day or night. The first Dispatch is published in
September 2002.
The MMWR Editorial Board is established and holds its first meeting.
MMWR weekly podcast series is established. The podcasts are MMWR’s first product for lay audiences.
MMWR’s first Deputy Editor is appointed. A second Deputy Editor is appointed in 2010.
MMWR establishes a presence on social media (Facebook and Twitter).

1950
1952
1960
1961
1967
1970
1977
1980
1981
1981
1982
1983
1990
1992
1992
1995
2001
2002
2006
2006
2009
2010

8

MMWR  /  October 7, 2011  /  Vol. 60

Supplement

FIGURE 2. The Bulletin of the Public Health, published by the U.S.
Marine-Hospital Service, July 13, 1878

CDC’s mission than NOVS’s. He enlisted help from colleagues
in Washington and at CDC. David J. Sencer, the future director of CDC who was then working at the Bureau of State
Services in Washington, weighed in on Langmuir’s side, as
did the Surgeon General’s Study Group and a task force that
had been appointed to consider the transfer. As Langmuir
later said in an interview, “[After] all sorts of pulling out
teeth by the roots without anesthesia and all kinds of internal
frictions, … on July 1st, 1960, we had the obligation, formal
duty, of issuing the weekly morbidity and mortality report”
(8). The Department of Health, Education, and Welfare formally approved the transfer on September 30, 1960. To make
MMWR functional at CDC, the Department transferred a
budget of $16,500 and 1.5 employee positions to CDC (David
J. Sencer, personal communication, August 10, 2010).
Langmuir named E. Russell Alexander as the first CDC
editor of MMWR but worked tirelessly on MMWR himself
(Table 2). During MMWR’s first 9 years at CDC, Langmuir
gave MMWR his highest priority, labored over the text of
each article, and approved gradual improvements. Over time,
Langmuir began using MMWR to change practices in state
and local health departments and clinicians (8). To make
state and local health departments’ work more prominent, he
required that authors of MMWR articles from state and local
health departments be listed first and that CDC authors be
listed only by the name of their program and not individually.
Langmuir also experimented with the use of an editorial note
to accompany the factual reports.

Bringing MMWR to CDC
In 1960, CDC was only 14 years old; it had been organized
in 1946 in Atlanta as an outgrowth of the federal agency,
Malaria Control in War Areas (6). In 1949, Langmuir came to
CDC, then known as the Communicable Disease Center, to
head the epidemiology branch. Early in his career, Langmuir
had worked at local and state health departments and had
recognized the crucial importance of vital statistics and public
health surveillance. During his early years at CDC, he noticed
that the staff at NOVS who received, compiled, and reported
federal surveillance statistics were not trained in epidemiology and, as a colleague later said, “had no obligation—or,
apparently, inclination—to analyze data rapidly and act on
the implications” (7). Langmuir became determined to move
the surveillance function and its accompanying publication,
MMWR, to CDC’s epidemiology branch.
To counteract ambivalence about the transfer at both
NOVS and CDC (7; David J. Sencer, personal communication, August 10, 2010), Langmuir worked hard to persuade
his superiors that the job of disease surveillance fit better into

The 1970s and 1980s
A turning point in the history of MMWR was Langmuir’s
appointment of Michael B. Gregg as MMWR editor in
1967 (Figure 3). Gregg became the longest-serving editor
in MMWR’s history and exerted a major effect on MMWR’s
personality, language, and scientific standards. Gregg had
come to CDC in 1966 and had worked under Langmuir
(9,10). Soon after Langmuir appointed him as MMWR Editor,
Gregg applied his literary skills to MMWR, editing each
article carefully to ensure that it was written in clear, compact
English and that it stuck to the epidemiologic findings (11;
Anne Mather, personal communication, August 17, 2010).†
During the 1970s, Gregg developed the editorial note into a
† Gregg

later wrote, “The MMWR is not a compilation of unsubstantiated information gathered by a variety of lay, semi-scientific or even scientific sources
to alarm, persuade, or otherwise convince the reader by subtle editorialization,
but rather the reports comprise the best available scientific data obtained by
professionals, carefully reviewed and articulated, shorn of modifiers, primarily
designed to bridge the gap between the traditional news media reports of events
on the one hand, and the 6–12 month to even 18-month delay before the
bloom of scientific publication on the other” (5).

MMWR  /  October 7, 2011  /  Vol. 60

9

Supplement

TABLE 2. MMWR Editors, Managing Editors, and Deputy Editors,
1961–2011
Years

FIGURE 3. Michael B. Gregg, circa 1968

Editor

1961–1962
1962–1963
1963–1964
1965–1966
1967–1988
1988–1998
1998–2005
2005–2006
2007–2010
2010–

E. Russell Alexander
P.R. Joseph
Lawrence K. Altman
D.J.M. MacKenzie
Michael B. Gregg
Richard A. Goodman
John W. Ward
Mary Lou Lindegren
Frederic E. Shaw
Ronald L. Moolenaar

1954–1965
1968–1970
1971–1972
1973–1974
1975
1975–1981
1982–1986
1987-1988
1988–2000
2000
2000–2002
2002–2003
2003–2008
2008–

P.D. Stolley
Priscilla B. Holman
Susan J. Dillon
Deborah L. Jones
Katherine A. Sherman
Anne Mather
Karen L. Foster
Gwendolyn A. Ingraham
Karen L. Foster
Caran R. Wilbanks (Acting)
Teresa F. Rutledge (Acting)
David C. Johnson (Acting)
Suzanne M. Hewitt
Teresa F. Rutledge

2009–
2010–

Christine G. Casey
John S. Moran

Managing Editor

Deputy Editor

consistent and valuable feature of each article; he took special
pride in these notes, which he observed were the most-read
part of MMWR articles and gave CDC a chance to point out
the implications of the facts presented (11). The editorial note
became the place where each MMWR report answers the “so
what?” question: what actions should be taken by readers (e.g.,
medical personnel, state and local health departments) as a
result of the information in the report.
One of Gregg’s most enduring contributions to MMWR
was to persuade the National Library of Medicine to include
content from MMWR in the Index Medicus (10). Beginning
in 1981, inclusion there would mean that all reports published
in MMWR would forever become part of the indexed medical
literature. Through Gregg’s steady improvements, gradually
MMWR became required reading at state and local health
departments and medical offices and within the health press.
In early May 1981, Gregg received a telephone call from
Wayne Shandera, an Epidemic Intelligence Service (EIS)
Officer assigned to the Los Angeles County Department of
Health (12). Shandera described five cases of Pneumocystis carinii
pneumonia in young men. The five men had in common that
they were previously healthy and had had sex with other men.
Pneumocystis pneumonia was seen mainly in persons with

10

MMWR  /  October 7, 2011  /  Vol. 60

Photo: CDC

cancer or other immunosuppressive conditions, and a group of
five cases in otherwise healthy young men was highly unusual.
The attending physician who had treated four of the men,
Michael Gottlieb, wanted to publish the cases in a medical
journal but knew that would take months (6). Shandera asked
Gregg whether he would be interested in publishing a description of the cases in MMWR. Gregg did not know quite what
to make of the cases but asked Shandera to submit a report
to MMWR (12). After consulting with colleagues at CDC,
Gregg published the report in MMWR on June 5, 1981 (13)
(Figure 4). Immediately after the article appeared, clinicians
across the country who had seen similar patients realized the
connection to the Los Angeles cases (12). Recognition of the
AIDS epidemic had begun. The first AIDS article in the peerreviewed medical literature appeared 4 months later (14).
Until the mid-1980s, CDC provided a free print subscription by airmail to anybody who requested one, and circulation
rocketed from approximately 6,000 in 1961 to 80,000 in 1981
and 120,000 in 1983. In 1982, the cost of MMWR printing

Supplement

FIGURE 4. First page of the first AIDS report, June 5, 1981

publishing weekly in its pages lead articles from MMWR (17).
That arrangement, too, continues today.§

The 1990s

and distribution came under scrutiny, and CDC director
William Foege was obliged to take “a painful departure from
our tradition” (15) and notify MMWR readers that CDC would
no longer provide unrestricted free distribution. Overnight,
free mailed subscriptions from CDC dropped from 120,000
to about 12,000. The drastic reduction in free distribution
prompted complaints from subscribers and the medical community. Foege, Gregg, and colleagues at CDC talked with
leaders in the medical press about how to fill the gap. On
February 24, 1983, the editor of the New England Journal of
Medicine, Arnold S. Relman, announced that the Journal’s
parent organization, the Massachusetts Medical Society, would
begin reprinting MMWR and selling subscriptions at $20.00
per year (16). That arrangement, at a current rate of $189 per
year, remains in effect, and the Society continues to reprint
all series of MMWR for approximately 5,500 paid subscribers
(Ann Russ, Massachusetts Medical Society, personal communication, September 7, 2010). In March 1983, George D.
Lundberg, the editor of the Journal of the American Medical
Association (JAMA), announced that JAMA would begin

Gregg stepped down as MMWR editor in 1988 and was succeeded by Richard A. Goodman. During Goodman’s tenure as
editor, two of MMWR’s priorities were to expand its content
and turn the articles toward specific public health actions. By
1990, MMWR’s circulation had rebounded to 45,000–50,000
(7), mostly through the Massachusetts Medical Society. The
national news media were covering CDC’s activities closely,
and several times each month MMWR articles were the source
of national news stories. By the early 1990s, MMWR had
published hundreds of articles on the burgeoning AIDS epidemic. One of the most influential was an article published
July 27, 1990, about transmission of HIV to patients by a
dentist in Florida (18), the first documented instance of HIV
transmission through a medical procedure. Publication of this
report received enormous attention by the media, dramatically
underscoring the sway of CDC and MMWR over public health
information (Richard A. Goodman, personal communication,
August 18, 2010).
By 1990, MMWR had become a series of four publications: the MMWR weekly, the annual Summary of Notifiable
Diseases, the CDC Surveillance Summaries, and Supplements.
The Surveillance Summaries series had been created in 1983 by
Stephen B. Thacker, the director of the CDC surveillance office
from which the MMWR emanated, to centralize and promote
surveillance activities of CDC programs (Stephen B. Thacker,
personal communication, August 17, 2010). Previously, CDC
surveillance data had been published and distributed by each
individual CDC program. The rising prominence of MMWR
placed more pressure on authors inside and outside CDC to
publish their findings quickly in MMWR. EIS Officers had a
new requirement to submit reports to MMWR as part of their
CDC training. Submissions to MMWR soared.
In the late 1980s, MMWR determined that just one type of
report consumed approximately one fourth of all text pages
in the MMWR weekly: official vaccination recommendations
from CDC’s Advisory Committee on Immunization Practices
(19; Richard A. Goodman, personal communication, August
18, 2010). To alleviate the problem and to accommodate
demand for space for reports of epidemiologic field investigations and other work, MMWR created the Recommendations
and Reports in 1990. Since then, the Recommendations and
Reports series has been MMWR’s main vehicle for publishing
the full spectrum of official CDC recommendations, from the
§ For

a time, the Ochsner Clinic also reprinted MMWR.

MMWR  /  October 7, 2011  /  Vol. 60

11

Supplement

diagnosis of tuberculosis to the vaccination recommendations
of the Advisory Committee on Immunization Practices.
The 1990s also marked MMWR’s first foray into electronic
publishing. Since the mid-1980s, CDC had made MMWR
available to state and local health departments and other entities through dedicated electronic systems operated through
telephone lines (20). In 1992, MMWR content became available through a file transfer protocol (FTP) server. However,
these systems were often expensive and difficult to use.
Beginning in 1993, CDC began to convert MMWR into electronic format and increase its availability through the Internet.
In January 1995, the publication made its editions available
both through FTP and the World-Wide Web (21; T. Demetri
Vacalis, personal communication, August 11, 2010). The new
Internet distribution quickly had an unanticipated benefit. In
1995, MMWR had never missed publishing a weekly issue (a
record that remains true today). In November of that year, 10
months after MMWR instituted electronic distribution, the
federal government shut down all but emergency functions
because of a budget impasse between the President and the
Congress. For its November 17, 1995, edition, MMWR had
to delay printing the weekly issue, but still released MMWR
on time through its new electronic capability (22).
In June 1996, on the occasion of CDC’s 50th anniversary,
MMWR published a special issue featuring CDC’s history and
the evolution of reporting public health data (23). In 1999, also
in recognition of CDC’s 50th anniversary, MMWR published
a compendium of selected reports that had appeared during
1961–1996 on such topics as smallpox, Legionnaires disease,
HIV/AIDS, and other major public health events covered in
MMWR (24).

The 2000s
The events of September 11, 2001, and the subsequent
anthrax attacks brought a major focus on bioterrorism and
emergency preparedness to CDC and MMWR. During the
2000s, other public health events also affected the path of
MMWR, including the advent of SARS, the expansion of
West Nile and emergence of monkeypox virus infections in the
United States, and greater national aspirations for the control
of influenza epidemics. At the same time, MMWR was obliged
to cope with a building maelstrom in the medical publishing
world spawned by the explosive growth of the Internet.
Goodman stepped down as editor in 1998 and was succeeded
by John W. Ward. One of Ward’s first jobs was to find a way
for MMWR to celebrate the coming new millennium. Jeffrey P.
Koplan, CDC director during 1998–2002, came up with the
idea of a series on the 10 great achievement of public health

12

MMWR  /  October 7, 2011  /  Vol. 60

in the previous century. MMWR began publishing the series
in April 1999 (25), and the articles became among the most
cited ever published by MMWR.
The new millennium was only months old when the attacks
of September 11 occurred, followed in October by the intentional releases of anthrax spores. MMWR published its first
article on the anthrax attacks on October 12, 2001 (26,27),
and for weeks published updates on the epidemiologic investigation and recommendations. In March 2003, when SARS
erupted around the world, MMWR began to publish articles
on the epidemic, updating the number of cases reported to the
World Health Organization, the number of deaths and related
public health alerts and information (28).
By 2002, most MMWR subscribers received the publication
by e-mail, which had supplanted postal letters as the main
method of communication between CDC and state and local
health departments. MMWR’s e-mail circulation was approximately 30,000, which when combined with the ongoing
print subscriptions mailed by CDC and the Massachusetts
Medical Society, gave a total circulation of about 50,000.¶
The occurrence of so many public health emergencies during
the early 2000s brought the realization that, during critical
events, MMWR could no longer wait until the routine weekly
issue on Friday to send critical information to readers (John
W. Ward, personal communication, August 4, 2010.). Before
2002, only once in its history had MMWR published an issue
on a day other than Friday, in January 1977 to announce
CDC’s discovery of the bacterium that caused Legionnaires
disease (David J. Sencer, personal communication, August 10,
2010). On September 13, 2002, MMWR published its first
“Dispatch,” a new form of urgent report that could be emailed
to readers at any time, day or night (29).
The early 2000s brought other changes as MMWR strove to
adapt to the rapidly changing communications world (Mary
Lou Lindegren, personal communication, August 9, 2010).
The MMWR series became more Web-centric, adapting its
editorial policies to match Web-based publication. In 2001,
MMWR’s graphical appearance changed from its longstanding 6- by 8-inch black-and-white format to a new 8½-inch
by 11-inch two-color format. To match the scope of CDC’s
work, MMWR’s content became more diverse (e.g., reviews
by CDC’s Guide to Community Health Services, more reports
on chronic disease and injuries, and a new one-page graphical snapshot of key public health statistics called QuickStats,
produced by CDC’s National Center for Health Statistics).
In 2002, CDC contributors to the weekly were for the first
time listed by name.
¶ The circulation of MMWR through the Massachusetts Medical Society in 2002

was 13,500 (19).

Supplement

Ward stepped down as the MMWR editor in 2005 and was
succeeded by Mary Lou Lindegren. In 2005, both Ward and
Lindegren believed that MMWR needed an advisory board
to provide independent advice to the MMWR editor. After 2
years of planning, the MMWR Editorial Board met for the
first time in June 2006, chaired by William L. Roper, a former
CDC director. Also during the mid-2000s, in response to findings from a CDC committee on the quality of evidence used
in CDC recommendations, for the first time MMWR listed
explicit guidelines for making official recommendations in
its pages and required contributors to state more clearly the
evidentiary basis of recommendations. MMWR also revamped
its production process; added new technologies such as RSS
feeds; and developed new content, such as a series of perspective
reports from past CDC directors and a compendium celebrating 60 years of public health science at CDC (30). MMWR also
increased its role in documenting the impact of global public
health initiatives (e.g., polio eradication, measles eradication,
global HIV control efforts), and copublished many articles with
the World Health Organization’s Weekly Epidemiological Record.
Lindegren was succeeded by Frederic E. Shaw in 2007 and
MMWR added its first deputy editor in 2009.** Beginning
October 2006, two new podcasts, broadcast in English and
Spanish, became the sixth component of the MMWR series.
They were MMWR’s first foray into products for lay audiences.
MMWR also revamped the graphical format of the series (the
first revision since 2001), added new report types to the weekly
(e.g., CDC’s Public Health Grand Rounds, mini-articles that
appear under the header, “Notes from the Field”), and instituted an MMWR presence on Facebook and Twitter. In 2010,
MMWR also implemented a suggestion from CDC’s new director, Thomas R. Frieden, by inaugurating the publication of
“Vital Signs,” a new coordinated CDC communication effort
anchored by scientific articles in MMWR (31). In April 2009,
the worldwide outbreak of pandemic influenza A (H1N1)
(then called swine influenza H1N1) began; MMWR reported
the first two cases on April 21, 2009 (32), then published
rapid-fire articles on the pandemic, including MMWR’s first
published articles in Spanish. By the end of 2010, MMWR
had published 45 articles on various aspects of the pandemic.
By 2007, the technology used by MMWR to distribute the
publication by e-mail had become antiquated. In February
2009, MMWR switched to a new Web-based system that made
subscribing to MMWR easier. This change, combined with
a huge public interest in 2009 pandemic (H1N1), vaulted
** Shaw served as Acting MMWR Editor in the summer of 2006 and became
Editor in January of 2007. He was succeeded by Ronald L. Moolenaar in
2010. MMWR’s first deputy editor is Christine G. Casey. Another deputy
editor, John S. Moran, was added in 2010.

MMWR’s electronic circulation from approximately 50,000 in
2007 to 100,000 in 2010. By August 2010, with the remaining print subscription base of about 13,000, MMWR’s total
circulation had reached almost 115,000, near the level at which
it stood before the budget cuts of 1982. Together with articles
reprinted to JAMA’s subscribers, approximately 1 million
monthly visits to the MMWR website, podcast downloads
of 50,000 per week, and MMWR followers on Facebook and
Twitter, by its 50th anniversary at CDC in 2011, MMWR
was seen by a bigger and broader audience than ever before.

The Future
When the Internet began to emerge into common use in
the early 1990s, no one could have imagined the revolutionary
effects it would have on medical and public health communications. One effect on MMWR has been to create competitors
for MMWR’s traditional mission of bridging the gap between
immediate news media reports of public health events and later
scientific publication (5). Today, medical journals are able to
publish scientific articles more quickly than before through
electronic means. During the recent outbreak of pandemic
(H1N1) influenza, The New England Journal of Medicine
electronically published information about the epidemiology
of the disease within just a few days of data collection (33).
In 1961, and for decades afterwards, MMWR was the only
way for CDC to mass-disseminate scientific information rapidly about public health events. Today, several other electronic
channels exist at CDC for rapid communications about public
health events: Epi-X (an electronic communication system for
public health officials), the Health Alert Network (HAN), the
Clinician Outreach and Communication Activity (COCA),
satellite or Internet-based conferencing, mass e-mails, and
informal posting on the Web. During the recent influenza
pandemic, CDC relied on all these channels to communicate
epidemiologic data and recommendations to state and local
health departments and the medical community and relied
especially heavily on informal postings on the Web. Ten years
from now, a historian who wishes to trace CDC’s work on
the pandemic will consult MMWR’s archives, but also will be
obliged to consult electronic materials on the Web and other
channels, if they are still accessible.
Despite these pressures, MMWR’s traditional role continues.
Informal Web postings, attractive as they might be, do not
receive the rigorous review and editing that MMWR content
does, nor are they indexed in MEDLINE, something that
authors still believe is important. Rapid public releases to the
news media or to health-care providers generally do not contain
the kind of detailed scientific information sought by public

MMWR  /  October 7, 2011  /  Vol. 60

13

Supplement

health and medical audiences. Medical journals, although
much more nimble than ever before, cannot publish state or
federal public health investigations within hours, nor replace
MMWR’s central role as the official voice of CDC, nor publish lengthy official CDC recommendations or surveillance
statistics. These functions will remain unique to MMWR into
the future. As the future unfolds, new roles for MMWR will
continue to appear as they have over the past 50 years, and
MMWR will evolve to meet the needs of public health.
Acknowledgements
This report is based on helpful interviews, editorial assistance,
and reviews by Karen L. Foster, Suzanne M. Hewitt, Anne Mather,
Teresa F. Rutledge, Myron G. Schultz, David J. Sencer, Stephen B.
Thacker, and T. Demetri Vacalis.
References
1. Langmuir AD. William Farr: founder of modern concepts of surveillance.
Int J Epidemiol 1976;5:13–18.
2. An Act to Prevent the Introduction of Contagious or Infectious Diseases
into the United States. Ch. 66, 20 Stat. 37 (1878).
3. US Marine-Hospital Service. Bulletin of the public health. No 1, July 13,
1878, Available at http://www.ncbi.nlm.nih.gov/pmc/articles/
PMC1764606/?page=1.
4. Anonymous. Public Health Reports: From yellow fever to international
health. Public Health Reps 1952;67:1–7.
5. Gregg MB. From morbidity and mortality to prevention and control.
Presentation at the American Medical Writers Association Meeting,
Atlanta, Georgia, September 30, 1980.
6. Etheridge EW. Sentinel for health: a history of the Centers for Disease
Control. Berkeley: University of California Press; 1992.
7. Thacker SB, Gregg MB. Implementing the concepts of William Farr:
the contributions of Alexander D. Langmuir to public health surveillance
and communications. Am J Epidemiol 1996;144(suppl):S23–8.
8. Langmuir AD, Interview [videotape]. Menlo Park, CA: Alpha Omega
Alpha Honor Medical Society; 1979.
9. Morens DM. In memoriam: Michael B. Gregg (1930–2008). Emerg
Infect Dis 2008;14:1476–8. Available at http://www.cdc.gov/EID/
content/14/9/1476.htm.
10. CDC. Michael B. Gregg, MD—1930–2008. MMWR 2008;57:802.

14

MMWR  /  October 7, 2011  /  Vol. 60

11. Gregg MB. Memorandum to Martha Katz, Acting Director of the CDC
Washington Office. May 8, 1985.
12. CDC. Twenty years of AIDS [videotape]. Atlanta: Crawford
Communications; 2001.
13. CDC. Pneumocystis pneumonia—Los Angeles. MMWR 1981;​
30:250–2.
14. Hymes KB, Cheung T, Greene JB, et al. Kaposi’s sarcoma in homosexual
men: a report of eight cases. Lancet 1981;2:598–600.
15. CDC. MMWR subscriptions. MMWR 1982;31:527..
16. Relman AS. New distribution of Morbidity and Mortality Weekly
Report. N Engl J Med 1983;308:452.
17. Lundberg GD. Getting the information out faster and some good news
about MMWR. JAMA 1983;249:1483.
18. CDC. Possible transmission of human immunodeficiency virus to a
patient in an invasive dental procedure. MMWR 1990;39:489–93.
19. Dowdle WR. Memorandum July 6, 1989.
20. CDC anonymous. Memorandum: Description and Justification,
Morbidity and Mortality Weekly Report. (undated, probably 1984).
21. CDC. Notice to readers: availability of electronic MMWR on Internet.
MMWR 1995;44:48–50.
22. CDC. Notice to Readers. MMWR 1995;44:845.
23. CDC. CDC’s 50th anniversary. MMWR 1996;45:525.
24. CDC. Highlights in public health. Landmark articles from the MMWR
1961–1996. MMWR 1999;48 (unnumbered supplement). Available at
http://www.cdc.gov/mmwr/pdf/other/highlite.pdf.
25. CDC. Ten great public health achievements—United States, 1900–1999.
MMWR 1999;48:241–3.
26. CDC. Ongoing investigation of anthrax—Florida, October 2001.
MMWR 2001;50:877.
27. CDC. Update: investigation of anthrax associated with intentional
exposure and interim public health guidelines, October 2001. MMWR
2001;50:889–93.
28. CDC. Outbreak of severe acute respiratory syndrome. MMWR 2003;​
52:226–8.
29. CDC. Investigation of blood transfusion recipients with West Nile virus
infections. MMWR 2002;51:823.
30. CDC. 60 Years of public health science at CDC. MMWR 2006;55(Suppl).
31. CDC. Vital signs: colorectal cancer screening among adults aged 50–75
Years—United States, 2008. MMWR 2010;59;808–12.
32. CDC. Swine influenza A (H1N1) infection in two children—Southern
California, March–April 2009. MMWR 2009;58:400–2.
33. Novel Swine-Origin Influenza A (H1N1) Virus Investigation Team,
Dawood FS, Jain S, et al. Emergence of a novel swine-origin influenza
A (H1N1) virus in humans. N Engl J Med 2009;360:2605–15.

Supplement

The Cornerstone of Public Health Practice:
Public Health Surveillance, 1961–2011
Lisa M. Lee, PhD
Stephen B. Thacker, MD
Office of Surveillance, Epidemiology and Laboratory Services, CDC
Corresponding author: Lisa M. Lee, PhD, Office of Surveillance, Epidemiology, and Laboratory Services, 1600 Clifton Road, N.E., MS E-94, Atlanta, GA
30333; Telephone: 404-498-6010; Fax: 404-498-6365; E-mail: [email protected].

Introduction
The roots of modern public health surveillance took hold
in 17th century Europe (1), but the seed for CDC’s role as
America’s national agency for collecting, analyzing, interpreting, and using data to protect the public’s health was firmly
planted only in 1961, when the Morbidity and Mortality
Weekly Report (MMWR) was transferred to what was then the
Communicable Disease Center (CDC; now the Centers for
Disease Control and Prevention) (2). The advent of MMWR
at CDC marked the beginning of CDC’s responsibility for
aggregating and publishing data weekly on nationally notifiable diseases and publishing the data annually in MMWR’s
Summary of Notifiable Diseases, United States.

The Beginnings of Modern Public
Health Surveillance in the
United States
In its earliest incarnation in the United States, surveillance
took the form of morbidity reporting. By 1925, the year all
states began reporting regularly, the expectations were limited
to collecting, compiling, and publishing statistics in weekly
reports. By the 1950s, however, simply compiling and reporting statistics clearly was insufficient to alleviate disease threats,
and the National Surveillance Program was started. That
program and the Malaria Surveillance Program, which had
started 2 years earlier, were based on the notion that effective
disease control cannot occur without implementing new ideas
and expanding use of data collected (3).
Nowhere was the idea of connecting public health surveillance data directly to public health action more successful than
during the 13-year global effort to eradicate smallpox. During
1966–1978, the initial tools for eradication were public education and mass vaccination. When the disease returned in some
areas thought to have reached elimination, timely, complete
surveillance and ring vaccination (i.e., administering vaccine
to persons in close contact with an infected patient) enabled
the program to turn the corner on eradication (4).

Effective national disease surveillance was an idea that captured the imagination of Alexander D. Langmuir, CDC’s chief
epidemiologist for 23 years. In 1963, in his sentinel paper published in the New England Journal of Medicine (5), Langmuir
separated the discipline of surveillance from the other activities
of public health and emphasized the importance of systematic
collection of pertinent data, consolidation and analysis of these
data into useful information, and dissemination of results to
persons who need to know and can take action. These concepts
were argued convincingly to the World Health Assembly as
the approach for monitoring communicable and noncommunicable health events; subsequently, surveillance systems were
developed, and findings from these systems were highlighted
in a special issue (volume 5, number 1) of the International
Journal of Epidemiology in 1976.
During the 50 years since Langmuir published his concept
of public health surveillance, developments in four areas have
changed the field: 1) national coordination, 2) technology
and informatics, 3) expansion beyond communicable diseases,
and 4) methodologic development. Through these, however,
the core definition and integrity of surveillance practice have
remained unchanged.

National Coordination of Public
Health Surveillance
The United States Constitution leaves responsibility for
public health practice primarily to the states as part of their
police powers (6). The federal government, however, retains
important roles. A major role in public health surveillance for
CDC is to provide the national epidemiologic profile, through
aggregation of surveillance data provided by the states, for the
most important diseases and conditions. Having accurate and
useful data requires that surveillance methods be coordinated
across the 50 states and other independent jurisdictions that
conduct data collection. Coordination includes establishment
of consistent case definitions, collection methods, and population coverage; it requires that the data be deduplicated to avoid

MMWR  /  October 7, 2011  /  Vol. 60

15

Supplement

inaccurate counting and that additional case information be
matched accurately to avoid data errors.
Recognition of the federal role in surveillance led to considerable work during the 1970s and 1980s, when national
coordination became a major emphasis for public health
surveillance. CDC and the Council of State and Territorial
Epidemiologists (CSTE), initially convened by CDC as the
Conference of State and Territorial Epidemiologists in 1952
to bring states together to address shared concerns regarding public health, annually spent hours in consultations and
symposia working on ways to coordinate public health surveillance. A report released in 1977 (J.L. Gale, Surveillance data:
quality, use and effect on public health divisions in local and
state health departments, unpublished report, 1977) called for
national surveillance activity coordination at CDC. A year later,
in 1978, the Consolidated Surveillance and Communications
Activity was established to respond to the recommendations of
Gale’s report. These activities fostered a new emphasis on the
scientific bases of surveillance, including the introduction of
new statistical methods (e.g., time-series analysis), formation of
the Surveillance Coordination Group that included the major
CDC programs and CSTE, and introduction of changes to the
MMWR weekly and Annual Summary of Notifiable Diseases.
These activities also led to the first comprehensive CDC plan
for public health surveillance, which was created in conjunction
with state partners and CSTE and appeared in 1985 (3). The
plan was designed to be flexible, with quick and easy updating,
done simply by the click of a three-ring binder and removal
and reinsertion of paper copies of critical sections. This document started with a surveillance definition that expanded the
one formulated by Langmuir and was agreed on by leaders of
all programs at CDC, both infectious and noninfectious diseases, and by CSTE. The plan emphasized the importance of
consistency in the seven steps that are now recognized as part
of any surveillance system: 1) system design, 2) data collection,
3) collation, 4) analysis, 5) interpretation, 6) dissemination/
communication, and 7) application to program.
National coordination of these steps was implemented in the
mid-1980s, when the most complex and well-funded national
surveillance system ever created in the United States began
to track cases of a new devastating immune-compromising
disease, acquired immunodeficiency syndrome (AIDS). What
eventually became the National HIV/AIDS Surveillance
System (7) began with great forethought and consideration of
the utility and applicability of the data collected at the national
and state levels. From the start, all cases reported to the system
were subject to the same case definition (8), and changes to the
case definition (9) went into effect uniformly on the same date
in every state. The same data elements were collected on the
same case report form in all states and reported by using the
16

MMWR  /  October 7, 2011  /  Vol. 60

same software. A system of deduplication activities to ensure
accurate case counting was implemented early and included
two key tools. The first tool emanated from a CSTE resolution
(10) and permitted cross-state communication of case information among the 50 states allowing public health surveillance
personnel to establish whether similar-looking cases were the
same individual reported more than once to the system. The
second tool was special statistical programming conducted on
the national database to search for possible duplicates (11).
This coordination continues today in the National HIV/AIDS
Surveillance System. Similar coordinated case reporting exists
for other nationally notifiable diseases (e.g., tuberculosis).
Today, public health surveillance remains an activity of the
states, but CDC continues to carry out its national role by coordinating national public health surveillance activities with the
states, CSTE, and other partners, including the Association of
State and Territorial Health Officers, the National Association
of City and County Health Officers, the Association of Public
Health Laboratories, the National Association for Public
Health Statistics and Information Systems, and the World
Health Organization (WHO). In 2009, these partners came
together with CDC to discuss challenges and a new vision for
the future of public health surveillance in the 21st century.

Technology, Informatics, and Public
Health Surveillance
Technologic advances began to improve the timeliness and
accuracy of public health surveillance in 1961 when CDC
implemented weekly telegraphic reporting by states for cases
of notifiable diseases. This technology remained state of the
art until 1975, when telephone reporting of nationally notifiable diseases began. In 1981, in addition to routine postcard
reporting, telephone reporting began including interactive
data transfer to a computer of the aggregate numbers for publication in MMWR. In 1984, CDC and six states piloted the
Epidemiologic Surveillance Project (ESP), which experimented
with electronic transfer of individual, de-identified case record
data to CDC. By 1989, all 50 states and selected territories were
participating in the National Electronic Telecommunications
System for Surveillance (NETSS), which still exists for data
transfer of the majority of nationally notifiable diseases. This
leap forward allowed unprecedented reductions in counting
and transcription errors and began the ability to remove human
error in several of the ongoing, systematic steps in a surveillance system (Figure).
Today, the role of public health informatics and information technology in public health surveillance is twofold: 1) to
improve timeliness and completeness of data collection and

Supplement

FIGURE. Optimal balance of human and automated inputs into
ongoing, systematic public health surveillance system activities*
Activities
Ongoing, systematic:
Planning &
system design

Data collection

Collation
Potential
Inputs:

Analysis

Automated
data systems

Potential
Inputs:
Human

Interpretation

Dissemination

Application to
program
* The size of the arrow indicates the relative human and automated inputs into
each activity

analysis and 2) to free human resources to focus on the areas
that require the most creative thought and to do the work
that technology cannot. The idealized mix of technologic
and human inputs into a public health surveillance system are
illustrated in this report (Figure). With effective informatics
tools, automated data systems can reach into electronic health
records and extract data for public health surveillance, relieving
the time-consuming and expensive “shoe-leather” data collection of chart reviews, paper forms, and morbidity cards that
have characterized traditional reporting. Health information
exchanges, which mobilize health information electronically
across organizations within a jurisdiction, will provide a timely,
efficient, and accurate means of data exchange and are an
example of an informatics tool that holds considerable promise
for public health.
During spring 1995, the CDC/ATSDR Steering Committee
on Public Health Information and Surveillance System

Development promulgated a blueprint for the agency’s highest priority objective: the creation of integrated public health
information and surveillance systems (12). The Steering
Committee, comprising representatives from all centers,
the institute, and offices at CDC, anticipated the impact of
health reform and accompanying data collection and storage
reforms and responded with sweeping recommendations for
an integrated information and surveillance system. The blueprint envisioned coordinating the disparate and fragmented
existing CDC surveillance systems to enhance functionality
and efficiency. The purpose was to minimize the need for
separate systems while maximizing the analytic value of the
data for public health action. However, attaining a meaningful integrated information and surveillance system has proven
more challenging than anticipated. Efforts continue to realize
a fully functional integrated electronic health information
system that begins at the clinical encounter and seamlessly
connects through the ongoing activities of public health surveillance, with federal investments in electronic health records
(13). Ensuring, through “meaningful use” requirements (14),
that public health is at the collective table in formulating the
requirements for software development is critical for the future
of public health surveillance.
Electronic algorithms that collate data from disparate sources
are critical to improving accuracy and timeliness as personbased surveillance records are connected across time. This
is especially important in registry-based surveillance systems
(e.g., HIV [7] and cancer [15]) where connecting subsequent
events to the correct case is essential for accurate analyses.
Using consistent statistical programs across jurisdictions and
across time allows for timely and comparable analyses, which
increasingly are important as the demands on public health
surveillance data increase (e.g., distribution of resources according to disease burden, or support of public health program
spending based on evidence of outcomes). In addition, new
computer programs and applications can help public health
programs better disseminate and communicate surveillance
results. For example, they can help create understandable and
interactive graphical representations of surveillance data that
can tell stories to different audiences, including those untrained
in health or public health (e.g., policymakers and the general
public). Reaching such audiences is a critical step for using
surveillance information for action, the last defining step of a
public health surveillance system.
Technology assists public health practitioners by spreading
information for action quickly and broadly, reaching program
partners and others responsible for action. An example occurred
at the start of the severe acute respiratory syndrome (SARS)
epidemic in 2003, when the need for a practical, consistent
case-finding tool quickly became evident. The Milwaukee
MMWR  /  October 7, 2011  /  Vol. 60

17

Supplement

Health Department was able to adapt an innovative informatics tool called the Regional Emergency Medical Internet
(REMI) to help find and triage SARS cases. The tool was
implemented rapidly and inexpensively in 27 hospital emergency departments (EDs) within 3 days after pilot-testing in
a single Milwaukee hospital (16). REMI had been designed
originally to assist EDs communicate when they must divert
ambulances and had been adapted by the health department
into a multi-ED surveillance system to tackle different syndromic illnesses, from heat-related syndromes to potential
biologic terrorism occurrences during international sporting
events (17). Another example of rapid, innovative adaptation of
surveillance technology occurred during the 2010 Deepwater
Horizon oil spill. CDC’s BioSense syndromic surveillance
system was used to help the five affected Gulf states monitor
the health (including mental health) of affected populations
after the spill. With a daily report from 86 coastal health-care
facilities, BioSense assisted with ongoing, up-to-the-day evaluation of possible health concerns (18).
Continued use of public health informatics promises more
efficiencies in public health surveillance. As time and mental
energy are freed for the surveillance scientist to focus on
developing and improving systems and applying evidence to
program implementation, usefulness of public health surveillance will continue to increase.

Expansion of Public Health
Surveillance beyond Communicable
Diseases
Until 1970, the “CDC” acronym stood for the Communicable
Disease Center, indicating the strict focus of CDC on prevention and control of communicable diseases. In 1970, the
agency’s name was changed to the Center for Disease Control;
then in 1980, to the Centers for Disease Control; and finally,
in 1992, to the Centers for Disease Control and Prevention.
The name change in 1970 signaled an expansion of CDC’s
mission to include prevention of unnecessary illness and premature death from all causes, infectious and noninfectious.
The focus of CDC’s activities broadened to include prevention of the major chronic conditions, including heart disease,
cancer, stroke, and unintentional injury, and their associated
risk behaviors (e.g., smoking, sedentary lifestyle, inadequate
nutrition, and use of passenger restraints). In 1984, a total of
15 states and CDC began collecting information monthly
about risk behaviors related to the leading causes of death
through the Behavioral Risk Factor Surveillance System (19).
In addition, CDC and its surveillance partners began communicating findings for action, including descriptions of the new
18

MMWR  /  October 7, 2011  /  Vol. 60

surveillance systems for injury (20), chronic diseases (21), and
environmental health tracking (22). MMWR, seeking a way
to standardize reporting of data from the increasing number
and types of surveillance systems and condition-specific surveillance reports, began publishing a new series called CDC
Surveillance Summaries in 1983, which continues today. The
first issue of CDC Surveillance Summaries contained reports
on multiple topics, including summer mortality from selected
cities and counties as reported by medical examiners, temporal
trends in malformation incidence reported to the birth defects
monitoring program, and psittacosis cases in the United States
in 1979 (23).
After the events surrounding September 11, 2001, interest
increased in using surveillance methods to detect unusual
health events that might indicate public health emergencies:
naturally occurring or human-made. Three outgrowths of
public health surveillance came from this. The first, syndromic
surveillance, is defined as the ongoing, systematic collection,
analysis, interpretation, and application of real-time (or near–
real-time) indicators for diseases and outbreaks that allow
for their detection before public health authorities otherwise
note them (24). Syndromic surveillance has been enhanced by
new technology and statistical methods that can help identify
disease patterns that would not be noted otherwise. The second outgrowth, biosurveillance, stemmed from a 2007 U.S.
homeland security presidential directive that addressed activities beyond the scope of public health surveillance to include
data collection for event detection, enhanced collection and
analysis for event characterization, further data collection for
situation awareness, and additional data collection for investigation and recovery activities (25). The third outgrowth was
the recognition that, with modern transportation, most of the
world’s populations live just one incubation period away from
other persons on the planet, and the health of one population
is related to the health of others. These developments have
kept CDC closely involved in international health (see global
health article in this issue), including international public
health surveillance. In 1992, CDC and WHO sponsored a
3-day international symposium on public health surveillance.
Held at the Carter Center in Atlanta, the symposium had three
goals: 1) foster an understanding of the role of public health
surveillance in reducing morbidity and mortality, 2) identify
topics for further development at future meetings, and 3) bring
experts together to describe a new global agenda for public
health surveillance (26).
A decade later, on the heels of the SARS epidemic (27) and
in the midst of threats of influenza pandemics, revision of
the International Health Regulations in 2005 (IHR 2005)
and their implementation in 2007 were crucial events for
international public health surveillance and served as a tool

Supplement

for countries to communicate about possible international
epidemics. IHR 2005 replaced the three notifiable diseases or
pathogens listed in the original IHR, written in 1969, with a
specifically defined “public health emergency of international
concern” (28). IHR 2005 requires all member states to report
a public health emergency of international concern within 24
hours. It also requires WHO to provide guidance and technical
assistance to member states to develop and strengthen public
health surveillance and response capacity. CDC participates
in similar technical assistance activities, with 35 self-sustaining
programs in 20 countries in which field epidemiology and
laboratory training programs help educate local public health
staff in surveillance methods as part of broader curricula since
1980 (29).

Advancement of Surveillance
Methods
Throughout the past 50 years of surveillance activities, public
health surveillance scientists have been developing methods to
advance the field by coordinating methods among systems,
applying advanced technology, and expanding systems to meet
the surveillance mission. Methods advancement has occurred
across the spectrum of the seven ongoing, systematic activities
of a surveillance system (Figure).
In 1986, CDC developed a comprehensive plan for what was
then called epidemiologic surveillance. This plan (30), developed
by CDC’s Surveillance Coordination Group, defined surveillance as follows:
The ongoing, systematic collection, analysis, and
interpretation of health data is essential to the planning,
implementation, and evaluation of public health practice,
closely integrated with the timely dissemination of these
data to those who need to know. The final link in the
surveillance chain is the application of these data to
prevention and control. A surveillance system includes
a functional capacity for data collection, analysis, and
dissemination linked to public health programs.
The 1986 plan included the first proposed method for evaluating a surveillance system (31), which was the precursor to
the more formal Guidelines for Evaluating Surveillance Systems
published in MMWR in 1988 (32) and its updated version,
Updated Guidelines for Evaluating Public Health Surveillance
Systems published in MMWR in 2001 (33).
The definition of public health surveillance has remained
stable across time, even as public health experts have debated
the purpose and meaning of surveillance. During the 1970s,
Langmuir argued that the boundaries of surveillance stopped

at “epidemiologic intelligence” and that it did not encompass
all of epidemiology (e.g., investigations and research) (34). In
1988, Thacker and Berkelman suggested a new name, public
health surveillance (35), to indicate its scope and context. In
2009, approximately 20 years after the last time the definition had been reconsidered, CDC gathered 100 surveillance
scientists to discuss special topics in public health surveillance
in the 21st century, including its definition. After careful
consideration addressing the drivers of health information in
the coming century, the group recommended maintaining
the existing definition of public health surveillance because it
remains applicable and flexible to accommodate public health
needs across the spectrum of topic areas. However, the group
recommended incorporating explicitly two key principles: 1)
the purpose of the activity must be to address a defined public
health problem or question and 2) the public health question(s)
must exist a priori, that is there must be a planned public health
purpose to the collection, storage, and use of the data.
A tenet of modern surveillance is that the utility of surveillance is determined largely by proper analysis of the data.
Herman Biggs, the 19th century physician who pioneered
public health surveillance in New York City, was known for
insisting that collected data be used to improve health, not
merely to keep “adding machines” busy (36). To be useful,
surveillance data must be converted into information for public health action. Fortunately, the tools used for analysis have
improved substantially since 1961. For example, the ability to
differentiate “noise” from true aberrations in the data has been
a problem keeping surveillance scientists occupied for years
(37). This problem plays out in surveillance for influenza, a
public health priority since 1918 when a system was established
by the U.S. Public Health Service in 50 cities based on death
certificates (and is still maintained today by CDC in 122 cities
and published weekly in MMWR). Influenza surveillance was a
priority for Langmuir, who worked with colleagues Serfling and
Sherman to develop a seasonal regression model that could help
analyze influenza mortality data more precisely than previous
methods based on the moving average (38). In 1979, pneumonia and influenza data were modeled by using time-series
analyses to identify aberrations in incidence (39,40); today,
other systems (e.g., anthrax [41] and syndromic surveillance
[42]) routinely use these methods to model surveillance data.
Application of epidemiologic study designs to examine efficacy
of different types of surveillance methods and approaches has
also been accomplished. In the early 1980s, two innovative
randomized clinical trials evaluated active surveillance strategies
compared with passive reporting. Both studies, one in Vermont
(43) and one in Monroe County, New York (44), demonstrated substantial improvements in completeness using active
surveillance strategies for communicable diseases. Differences
MMWR  /  October 7, 2011  /  Vol. 60

19

Supplement

in improvement were observed by disease and report source,
leading to the conclusion that in the analysis of surveillance
data, knowing and attending to the local context is desirable.
This conclusion remains critically important today.
By the early 1990s, many schools of public health in the
United States had begun to focus on the science of public
health surveillance, and the lack of a textbook was obvious. Until Public Health Surveillance was published in 1992
(45) and the first edition of Principles and Practice of Public
Health Surveillance was published in 1994 (46), surveillance
practitioners were able to rely only on journal articles, consultations convened by CDC, and professional exchanges to
share methodologic advances and preferred practices. Now
the Principles text is in its third edition (47), and additional
texts have been published, including one devoted to statistical
principles and methods of public health surveillance (48) and
another to infectious disease surveillance (49). As the science
of public health surveillance continues to evolve and the tools
of public health informatics become integral to the work of
surveillance practitioners, methods will continue to develop
that enable the public health epidemiologist to put data to use
in the most effective way.

The Future of Public Health
Surveillance
Evidence-based decision making in public health begins with
surveillance—and the demands on health data continue to
increase. The ways of knowing about the health of a community also continue to evolve as information technology eases the
effort to collect, collate, store, analyze, and disseminate data.
The integrity of the discipline of public health surveillance has
held fast for the past 50 years and most likely will continue for
the next 50 and beyond. The tools available to public health
surveillance practitioners and scientists will change as technology improves efficiency and frees practitioners to attend
to creative problem solving in such critical areas as program
planning and applying data to action. CDC will continue to
evaluate its efforts and move the field forward, welcoming the
opportunities that lie ahead.
References
1. Surveillance [editorial]. Int J Epidemiol 1976;5:3–7.
2. Thacker SB. Historical development [Chapter 1]. In: Lee LM, Teutsch
SM, Thacker SB, St Louis ME, eds. Principles and practice of public
health surveillance. 3rd ed. New York, NY: Oxford University Press;
2010: 1–17.
3. CDC. Manual of procedures for national morbidity reporting and public
health surveillance activities. Atlanta: US Department of Health and
Human Services, CDC; 1985.

20

MMWR  /  October 7, 2011  /  Vol. 60

4. World Health Organization. The global eradication of smallpox: final
report of the Global Commission for the Certification of Smallpox
Eradication. Geneva, Switzerland: World Health Organization; 1980.
5. Langmuir AD. The surveillance of communicable diseases of national
importance. N Engl J Med 1963;268:182–92.
6. Goodman RA, Kocher PL, O’Brien DJ, Alexander FS. The structure of
law in public health systems and practice [Chapter 2]. In: Goodman
RA, Hoffman RE, Lopez W, Matthews GW, Rothstein MA, Foster KL,
eds. Law in public health practice. 2nd ed. New York, NY: Oxford
University Press; 2007:45–69.
7. Glynn MK, Lee LM, McKenna MT. The status of national HIV case
surveillance, United States 2006. Public Health Rep 2007;122(Suppl 1):​
63–71.
8. CDC. Update on acquired immune deficiency syndrome (AIDS)—
United States. MMWR 1982;31:507–8, 513–4.
9. CDC. Revised surveillance case definitions for HIV infection among
adults, adolescents, and children aged <18 months and for HIV infection
and AIDS among children aged 18 months to <13 years—United States,
2008. MMWR 2008;57(No. RR-10).
10. Council of State and Territorial Epidemiologists (CSTE), Infectious
Disease Committee. HIV case reporting: reciprocal notification. Atlanta,
GA: Council of State and Territorial Epidemiologists; 2001. Position
statement 2001-ID-04. Available at http://www.cste.org/dnn/
AnnualConference/PositionStatements/tabid/191/Default.aspx.
11. Glynn MK, Ling Q, Phelps R, Lee LM. Accurate monitoring of the
HIV epidemic in the United States: case duplication in the national
HIV/AIDS surveillance system. J Acquir Immune Defic Syndr
2008;47:391–6.
12. CDC. Integrating public health information and surveillance systems.
Atlanta, GA: US Department of Health and Human Services, CDC;
1995. Available at http://www.cdc.gov/nedss/Archive/katz.pdf.
13. Cunningham R. Stimulus bill implementation: expanding meaningful
use of health IT. NHPF Issue Brief 2009;(834):1–16.
14. Anonymous. Meaningful use—final at last. Final rule adds flexibility to
objectives, eases measures. J AHIMA 2010;81(8):18–9.
15. CDC. National Program of Cancer Registries. United States cancer
statistics, technical notes. Atlanta, GA: US Department of Health and
Human Services, CDC; 2010. Available at http://www.cdc.gov/cancer/
npcr/uscs/2006/technical_notes/.
16. Foldy S, Barthell EN, Silva J, et al. SARS surveillance project—Internetenabled multiregion surveillance for rapidly emerging disease. In:
Syndromic surveillance: reports from a national conference, 2003.
MMWR 2004;53(Suppl):215–20.
17. Foldy SL. Linking better surveillance to better outcomes. In: Syndromic
surveillance: reports from a national conference, 2003. MMWR
2004;53(Suppl):12–7.
18. CDC. Emergency preparedness and response: health surveillance—Gulf
oil spill 2010. Atlanta, GA: US Department of Health and Human
Services, CDC; 2010. Available at http://www.bt.cdc.gov/gulfoilspill2
010/2010gulfoilspill/health_surveillance.asp.
19. CDC, National Center for Chronic Disease Prevention and Health
Promotion. Behavioral Risk Factor Surveillance System—BRFSS history.
Atlanta, GA: US Department of Health and Human Services, CDC;
2008. Available at http://www.cdc.gov/brfss/history.htm.
20. Graticer PL. The development of state and local injury surveillance
systems. J Safety Res 1987;18:191–8.
21. Thacker SB, Stroup DF, Rothenberg RB. Public health surveillance for
chronic conditions: a scientific basis for decisions. Stat Med
1995;14:629–41.
22. Thacker SB, Stroup DF, Parrish RG, Anderson HA. Surveillance in
environmental public health: issues, systems, and sources. Am J Public
Health 1996;86:633–8.
23. CDC. [Multiple reports.] MMWR Surveillance Summaries 1983;32(No.
SS-1):1–42.

Supplement

24. Sosin DM. Syndromic surveillance: the case for skillful investment.
Biosecur Bioterror 2003;1:247–53.
25. Sosin DM, Hopkins RS. Public health surveillance for preparedness and
emergency response: biosurveillance for human health [Chapter 14]. In:
Lee LM, Teutsch SM, Thacker SB, St Louis ME, eds. Principles and
practice of public health surveillance. 3rd ed. New York, NY: Oxford
University Press; 2010:306–20.
26. CDC. Proceedings of the 1992 International Symposium on Public
Health Surveillance. MMWR 1992;41(Suppl):1–218.
27. CDC. Outbreak of severe acute respiratory syndrome—worldwide,
2003. MMWR 2003;52:226–8.
28. World Health Organization (WHO). Communicable disease surveillance
and response, international health regulations (2005). Geneva,
Switzerland: WHO; 2008. Available at http://www.searo.who.int/en/
section10/section369_9695.htm.
29. CDC. Center for Global Health. 2010 Field epidemiology and
management capacity building programs [poster]. Atlanta, GA: US
Department of Health and Human Services; CDC; 2010. Available at
http://www.cdc.gov/globalhealth/FETP/pdf/factoid_poster.pdf.
30. CDC. Comprehensive plan for epidemiologic surveillance. Atlanta GA:
US Department of Health and Human Services, CDC; 1986.
31. Thacker SB, Parrish RG, Trowbridge FL. A method for evaluating systems
of epidemiological surveillance. World Health Stat Q 1988;41:11–8.
32. Klaucke DN, Buehler JW, Thacker SB, et al., and the Surveillance
Coordination Group. Guidelines for evaluating surveillance systems.
MMWR 1988;37(No. SS-5).
33. CDC. Updated guidelines for evaluating public health surveillance
systems: recommendations from the Guidelines Working Group.
MMWR 2001;50(No. RR-13).
34. Langmuir AD. Evolution of the concept of surveillance in the United
States. Proc R Soc Med 1971;64:681–4.
35. Thacker SB, Berkelman RL. Public health surveillance in the United
States. Epidemiol Rev 1988;10:164–90.
36. Fairchild AL, Bayer R, Colgrove J. Searching eyes: privacy, the state, and
disease surveillance in America. Berkeley, CA: University of California
Press; 2007.

37. CDC. Proposed changes in format for presentation of notifiable disease
report data. MMWR 1989;38:805–9.
38. Serfling RE, Sherman IL, Houseworth WJ. Excess pneumonia-influenza
mortality by age and sex in three major influenza A2 epidemics, United
States, 1957–58, 1960 and 1963. Am J Epidemiol 1967;86:433–41.
39. Choi K, Thacker SB. An evaluation of influenza mortality surveillance,
1962–1979: I. Time series forecasts of expected pneumonia and influenza
deaths. Am J Epidemiol 1981;113:215–26.
40. Choi K, Thacker SB. An evaluation of influenza mortality surveillance,
1962–1979: II. Percentage of pneumonia and influenza deaths as an
indicator of influenza activity. Am J Epidemiol 1981;113:227–35.
41. Buckeridge DL, Switzer P, Owens D, Siegrist D, Pavlin J, Musen M. An
evaluation model for syndromic surveillance: assessing the performance
of a temporal algorithm. In: Syndromic surveillance: reports from a
national conference, 2004. MMWR 2005;54(Suppl):109–15.
42. Ozonoff A, Forsberg L, Bonetti M, Pagano M. Research methods
bivariate method for spatio-temporal syndromic surveillance. In:
Syndromic surveillance: reports from a national conference, 2003.
MMWR 2004;53(Suppl):59–66.
43. Vogt RL, LaRue D, Klaucke DN, Jillson DA. Comparison of an active
and passive surveillance system of primary care providers for hepatitis,
measles, rubella, and salmonellosis in Vermont. Am J Public Health
1983;73:795–7.
44. Thacker SB, Redmond S, Rothenberg RB, Spitz SB, Choi K, White
MC. A controlled trial of disease surveillance strategies. Am J Prev Med
1986;2:345–50.
45. Halperin W, Baker EL, eds. Public health surveillance. New York, NY:
Van Nostrand Reinhold; 1992.
46. Teutsch SM, Churchill RE, eds. Principles and practice of public health
surveillance. New York, NY: Oxford University Press; 1994.
47. Lee LM, Teutsch SM, Thacker SB, St Louis ME, eds. Principles and
practice of public health surveillance. 3rd ed. New York, NY: Oxford
University Press; 2010.
48. Brookmeyer R, Stroup DF, eds. Monitoring the health of populations:
statistical principles and methods for public health surveillance. New
York, NY: Oxford University Press; 2004.
49. M’ikanatha NM, Lynfield R, Van Beneden CA, de Valk H. Infectious
disease surveillance. Malden, MA: Blackwell; 2007.

MMWR  /  October 7, 2011  /  Vol. 60

21

Supplement

Evolution of Epidemic Investigations and Field Epidemiology during
the MMWR Era at CDC — 1961–2011
Philip S. Brachman, MD1
Stephen B. Thacker, MD2
1Rollins School of Public Health, Emory University, Atlanta, Georgia
2Office of Surveillance, Epidemiology and Laboratory Services, CDC, Atlanta, Georgia
Corresponding author: Philip S. Brachman, MD, Rollins School of Public Health, Emory University, 1518 Clifton Road, Atlanta, GA 30322. Telephone:
404-727-0199; Fax: 404-272-4590; E-mail: [email protected].

Introduction
Since 1946, CDC has provided rapid assistance to states,
federal agencies, international organizations, and ministries of
health, often through formal requests for epidemic-assistance
investigations (Epi-Aids) (1). The Epi-Aid mechanism provides CDC with the agility to respond rapidly to serious and
urgent public health crises. Epi-Aids operationalize the tenets
of field epidemiology and are used to provide information, as
quickly as possible, on which the processes of selecting and
implementing interventions can be based to lessen or prevent
illness, injury, or death (2,3).
A total of 4,997 Epi-Aids have been conducted, of which
4,673 (94%) have occurred since 1960. Of the 556 international investigations, 551 (99%) have occurred since MMWR
was transferred to CDC in 1960. Approximately 90% of these
investigations have involved the approximately 3,000 Epidemic
Intelligence Service officers (EISOs) who have trained at CDC
since the program was initiated in 1951; however, only 218
EISOs came to CDC before MMWR arrived. EISOs assigned
to state and local health departments conduct additional
investigations within the states to which they are assigned.
During the past 50 years, EISOs collectively have conducted
approximately 5,000 state-based investigations without using
the formal Epi-Aid request mechanism.
The goal of Epi-Aids is to control an epidemic and to
prevent future epidemics attributable to the same or related
causes. The specific objectives of an investigation are to define
the parameters of the epidemic (i.e., time of illness onset and
conclusion of the epidemic, number of cases, and morbidity
and mortality), to identify control or prevention measures, and
possibly to identify new data relative to the epidemiology of the
health problem. Epi-Aids always are performed collaboratively
with partners domestically or internationally.
Justification for investigating epidemics include
• increased disease or injury severity (e.g., its morbidity or
mortality or other determinants of severity);
• occurrence of a rare or unknown disease or a change in
the pattern of the disease’s occurrence;

22

MMWR  /  October 7, 2011  /  Vol. 60

• opportunity to identify new information (e.g., risk factors
previously unassociated with that disease or a change in
transmission method);
• occurrence among a particular population (e.g., children
or older persons);
• public or political concern;
• opportunity to conduct research on a specific disease; and
• opportunity to train personnel (e.g., EISOs or state and
local field investigators) in the methodology of field
investigations.
The 13 steps in an epidemic field investigation (Box) are
adaptable to the circumstances of the problem, resources available, or cause or suspected cause of the disease. Altering the
order of the steps might be necessary (e.g., possibly instituting
control measures before completing data analyses), but all of
the steps should be completed. These steps are as valid today
as they were during the first field investigations over a half
century ago, but the methodology of field investigations has
evolved, as has the complexity of epidemics.
Four evolutionary changes throughout the past 50 years have
resulted in more comprehensive investigations, as observed
through MMWR. They include
• improved tools in science, technology, and communication;
• broader scope both in terms of geography and the nature
of the public health problems under investigation;
• a better trained and equipped workforce that includes not
only epidemiologists, public health advisors, microbiologists, and statisticians, but also behavioral and social scientists, economists, informaticians, toxicologists, and
chemists; and
• new or changed roles for CDC’s public health partners
(e.g., U.S. Environmental Protection Agency, Department
of Justice, Department of Housing and Urban
Development, Department of Homeland Security, and
Federal Bureau of Investigation and local law enforcement)
and enhanced collaborations with the Indian Health
Service; the U.S. Department of Agriculture; the Food
and Drug Administration; the National Institutes of
Health; the World Health Organization; and the private

Supplement

BOX. The 14 steps of an epidemic investigation

1. Confirm the existence of an epidemic.
2. Verify the diagnosis.
3. Develop a case definition.
4. Develop a case report form.
5. Count the cases (i.e., an approximate analysis).
6. Orient the data (i.e., time, place, and person).
7. Analyze the data (e.g., agent, transmission,
and host).
8. Develop a hypothesis.
9. Test the hypothesis.
10. Plan and implement control and prevention
measures.
11. Evaluate the implemented measures.
12. Establish or improve the public health surveillance.
13. Write a report.
14. Plan and conduct additional studies.
sector, including the business community, academia,
community-based organizations, health plans, professional
societies, volunteer agencies, and international organizations.
Before MMWR was transferred to CDC in 1960, most
Epi-Aids were conducted in response to infectious agents,
although environmental problems, including disasters, also were
addressed. Subsequent years continued to include investigations of infectious disease epidemics but increasingly included
environmental exposures, birth defects, genetic diseases,
reproductive health, tobacco, cancer, unintentional injury,
violence, legal debate, and terrorism. These Epi-Aids heralded
expansion of CDC’s mission and included new methods in
statistics and applied epidemiology. Recommendations from
these investigations have led to implementation, evaluation, or
modification of public health policies. For example, during the
1970s, salmonellosis among children throughout the country
was investigated, and the risk factor was contact with baby
semi-aquatic turtles sold in pet stores. Subsequently, sale of
these turtles was banned (4). During the 1990s, an epidemic of
Escherichia coli O157:H7 diarrhea was investigated, and the risk
factor was identified as eating undercooked hamburgers served
at multiple fast-food outlets of one chain (5). A new policy of
serving only well-cooked hamburgers was implemented.
The tools available to epidemiologists have evolved since
1961 and have been adapted to address whatever emergent
health problems arise. Evolution of statistical methods in the
acute setting of the Epi-Aid reflects a similar pattern in other
public health disciplines (6). Especially notable are 1) the
increased use of multivariate modeling beginning in the late
1970s, paralleling advances in computer hardware, especially

the laptop, and 2) advances in computer software, most notably
the CDC-sponsored Epi Info, an open-source software package
developed in the 1980s for practicing epidemiologists and now
translated into 14 languages (7).
Similarly, advances in laboratory practice have kept pace with
the complexities of the investigations (8). For example, in 1961,
the distance between the food source and the dinner table was
considerably shorter than today, when a substantial amount of
food is transported across the United States or imported from
abroad. A public health official 50 years ago usually could not
detect an outbreak until a substantial number of cases emerged
in a single area or from a single event (e.g., a picnic or party).
Today, in contrast, use of pulsed-field gel electrophoresis to create a DNA fingerprint enables associating a limited number of
cases of a disease throughout a wide geographic area with a single
common source. PulseNet, the laboratory-based foodborne
diseases surveillance system, benefits not only from enhanced
information science but also from increased diagnostic specificity (9). An example of the importance of this new technology
was the epidemic of Salmonella enterica serotype Tennessee
caused by contaminated peanut butter products in 2006–2007,
with cases occurring in 47 states (9,10). DNA identification
demonstrated that the cause of the epidemic was peanut butter
from one factory, which when investigated, revealed multiple
problems in its production process. Because the epidemiologic
capacity of state and local health departments is higher now than
in former years, for large outbreaks, CDC’s role today often has
become one of national coordination of multiple state-based
investigations. EISOs in the field join with state and local colleagues to conduct parts of a larger nationwide investigation.
These advances, as well as others (e.g., geographic information systems), have enabled extraction of more data from field
investigations and have increased the ability to determine the
cause of an adverse health outcome. Descriptive epidemiology
alone can help determine causation, but increasing knowledge of
the multifactorial causes of disease has made involvement of the
laboratorian and statistical analyses of the data of prime importance in deriving valid conclusions regarding cause and effect.

Steps in an Investigation
Despite the availability of new technology, what has not
changed is the need for careful and thorough data collection
and rigorous analysis of those data, thoughtful interpretation
of the findings, and the willingness to continue to question
the findings while confronted with the primary objective — to
control a problem quickly and effectively. The essential steps
remain the same as in 1960.

MMWR  /  October 7, 2011  /  Vol. 60

23

Supplement

When epidemiologists receive information about a possible
epidemic, they should confirm its existence by comparing
reported data with public health surveillance data collected
during previous years (Box). If surveillance data for a particular
disease or syndrome are unavailable, local health officials might
be able to provide an informal assessment of past occurrence of
the condition within their community. For many outbreaks,
investigators can help confirm the diagnosis by submitting
specimens for examination to a state or local laboratory, or
sometimes to CDC. However, for some outbreaks, methods
of confirmation are unavailable, and the investigation has to
be initiated without confirmation of the diagnosis.
In planning participation in an investigation, the investigator
must consider what materials should be taken into the field
that will be unavailable locally. This might include specimen
collection equipment; laboratory equipment; a calculator; a
laptop computer; a generic or standardized questionnaire;
reference material about the disease; and possibly, personal
protective equipment. In 1961, neither the calculator nor
the laptop was available. Specimen collection and laboratory
equipment, as well as personal protective equipment, have
changed dramatically, and today these tools often are available
locally. Today, many investigations that would have resulted
in an Epi-Aid request to CDC are handled locally, although
still often reported in MMWR (11).
For Epi-Aids involving invited CDC staff, upon arriving at
the scene of the epidemic, investigators meet with the local
health authorities who requested assistance to discuss the
information that has been developed locally. An immediate
decision should be made regarding who will be in charge of
the investigation and who will provide media reports. The
investigators should, with appropriate permissions, examine
selected patients to verify the diagnosis and develop a differential diagnosis of the cause of the outbreak. From the initial
assessment of the clinical and epidemiologic information, a
case definition should be established. Depending on the nature
of the disease and the objectives of the investigation, the case
definition should be either broad or narrow, which influences
its sensitivity and specificity.
Data collected every day should be analyzed at the end of that
day because identifying a control measure or measures before
all cases have been recognized might be possible. Clearly this
depends on the epidemic but is an important consideration
in all investigations. For example, an epidemic of hepatitis A
in Pascagoula, Mississippi, in 1961, might have disrupted
production by a local company of atomic submarines for the
U.S. Navy had it continued (12). Upon arrival in Pascagoula,
by using a local directory, the investigating epidemiologist

24

MMWR  /  October 7, 2011  /  Vol. 60

contacted patients by telephone. After completing interviews
with selected patients, the epidemiologist contacted an equal
number of controls. An analysis of these data at the end of the
first day of the investigation strongly indicated that ingestion of
raw shellfish was the risk factor involved. The epidemiologist
was able to come to this conclusion before interviewing all of
the patients. On the basis of these early findings, a decision
was made to publicize the problem and to recommend that
raw shellfish no longer be eaten. This action terminated the
occurrence of new exposures; after completing interviews with
all patients, the initial preliminary conclusion was confirmed.
Early in an investigation, categorizing cases as possible, probable, or confirmed on the basis of available data and knowledge
is often necessary. An example of the importance of categorization occurred during the investigation of Legionnaires disease
in Pennsylvania in 1976. The initial case definition required
that patients had been in the main conference hotel. Illnesses
of certain other patients met the clinical case definition except
that they had not been in the hotel; thus their illnesses were
put in a separate category called “Broad Street pneumonia.”
Later, after the etiologic agent was identified and a serologic test
developed, the Broad Street pneumonia cases were recognized
as cases of Legionnaires disease, just as the cases in the hotel.
The Board Street pneumonia cases were included in the final
tabulation for the outbreak.
The 1976 Legionnaires disease investigation also illustrates
the key role of MMWR in keeping the medical and public
health communities informed through updates in the weekly
report. The first report was published less than a week after
CDC was notified of the epidemic (13). Four more updates
followed, with the last reporting identification of the bacterium
that caused the disease (14) 11 months before publication in
a peer-reviewed journal (15). This last report was also the first
MMWR article published on a day other than Friday, highlighting the urgency in reporting the findings.
After all the patients have been interviewed during an investigation, the data should be oriented by time, place, and person.
Then a hypothesis should be developed on the basis of the data
that have been collected. It should be a unifying hypothesis
(i.e., one risk factor related to the epidemic), recognizing that
multiple risk factors might be involved. If uncertainty exists
about the hypothesis, an analytic investigation (e.g., a casecontrol or cohort study) might be needed. After a hypothesis
has been identified that fits the facts, corresponding control
and prevention measures should be determined and implemented. Surveillance must be maintained to evaluate whether
the hypothesis was correct and the control strategy is working. If the number of new cases decreases and the decrease is
believed to result from the control measures, the investigation

Supplement

can be completed by writing and disseminating the final report.
However, if cases continue to occur, the investigation has to
be continued and different hypotheses tested. This happened
during an outbreak of S. enterica serotype Saintpaul in 2008
in which approximately 1,400 persons in 43 states, the District
of Columbia, and Canada were infected (16). Preliminary
evidence implicated tomatoes as the transmission vehicle, but
further epidemiologic and microbiologic investigations identified jalapeno and serrano peppers as the primary vehicles.
Recently epidemiologists have used the Internet as a tool for
data collection, although the validity of that use remains under
scrutiny. As noted elsewhere in this supplement (17), MMWR
can reach tens of thousands of public health professionals in
a very short time. The fact that the weekly edition can, in
fact, be published electronically at any time, day or night, can
facilitate case ascertainment in an ongoing investigation. Along
with the effective outreach of Epi-X (a CDC-managed secure
communications network for public health professionals) to
public health partners, regional, national, and international
case ascertainment is expanded (18). Meanwhile, the WorldWide Web has opened channels of communication that are
more timely and far reaching than could have been imagined
in 1961. Well-crafted, timely, and accurate updates of an investigation help the medical and public health communities, as
well as the public, stay abreast of ongoing investigations, and
they assist in implementing timely interventions to protect
the public.
For CDC epidemiologists investigating outbreaks in the
field, just as in 1960, writing a report is critically important.
The report provides local public health departments an explanation of the parameters and the epidemic’s cause, which
enables timely and effective public health action. A secondary
benefit of a report is its value as a useful training document for
current staff and incoming epidemiologists. The report should
identify the risk factors that resulted in the epidemic, and the
report should be disseminated to the population involved in the
epidemic to educate the public about control and prevention
measures. Also, the report can be distributed to other public
health professionals to help prevent a future similar problem.
The results of an investigation often indicate the need for
other studies related to the disease or injury. For example,
investigation of epidemics of Ebola virus hemorrhagic fever
identified control measures (e.g., preventing contact with
bloody secretions from patients or contaminated needles and
syringes). What remains unknown and continues to be investigated is the reservoir for Ebola virus, which might be another
mammal (e.g., primates) (19).

Future of Epidemic Investigations
New science and technology will continue to improve the
epidemiologist’s approach to outbreak investigation. Rapid
technology development in the laboratory has improved
diagnostic precision and reduced the time necessary to make a
diagnosis. These improvements should continue, for example,
to identify pathogens in imported foods at the place of importation and among persons who now travel more extensively
and more rapidly around the globe. Similarly, increased use
of electronic health records will facilitate more timely and
accurate data collection as well as real-time dissemination of
recommended control measures to clinicians and health-care
facilities. Statisticians continue to develop new statistical methods that will provide insights through refined data analysis. For
example, mathematical modeling, especially in complex and
time-consuming investigations (e.g., pandemic influenza) can
enable application of control measures to reduce the number
of cases that are epidemic related. Improved techniques for
training also need to be developed so that the technology of
epidemic investigations can be used effectively by public health
personnel both in the United States and internationally.
Alexander D. Langmuir, the man who brought MMWR to
CDC in 1960, would be pleased with its first 50 years at CDC.
It still often publishes the first scientific report of an unfolding epidemic investigation, and the reports continue through
the different stages of the outbreak or incident. For example,
on April 21, 2009, MMWR published a rapid report of the
first cases of 2009 pandemic influenza A (H1N1) (20), and
then published 45 articles on the virus and the pandemic in
the subsequent several months, many reporting on ongoing
investigations and others providing recommendations based
on the findings of those investigations. Just as Langmuir
envisioned, MMWR remains an important mechanism for
reporting epidemic investigations in a timely and credible way.
References
1. Thacker SB, Stroup DF, Sencer DJ. Epidemic assistance by the Centers
for Disease Control and Prevention: role of the Epidemic Intelligence
Service. Am J Epidemiol 2011. In press.
2. Gregg MB, ed. Field epidemiology. 3rd ed. New York, NY: Oxford
University Press; 2008.
3. Koo D, Thacker SB. In Snow’s footsteps: commentary on shoe-leather
and applied epidemiology. Am J Epidemiol 2010;172:737–9.
4. Lamm SH, Taylor A Jr, Gangarosa EJ, et al. Turtle-associated
salmonellosis. I. An estimation of the magnitude of the problem in the
United States, 1970--1971. Am J Epidemiol 1972;95:511--7.
5. Bell BP, Goldoft M, Griffin PM, et al. A multistate outbreak of Escherichia
coli O157:H7–associated bloody diarrhea and hemolytic uremic
syndrome from hanburgers: the Washington experience. JAMA
1994;272:1349–53.

MMWR  /  October 7, 2011  /  Vol. 60

25

Supplement

6. Stroup DF, Lyerla RA. History of statistics in public health at CDC
1960–2010: the rise of statistical evidence. In: Public health then and
now: celebrating 50 years of MMWR at CDC. MMWR 2011;60(Suppl).
7. CDC. Epi Info™. Atlanta, GA: US Department of Health and Human
Services, CDC; 2011. Available at http://www.cdc.gov/epiinfo.
8. Dowdle WR, Mayer LW, Steinberg KK, Ghiya ND, Popovic T.
Laboratory contributions to public health. In: Public health then and
now: celebrating 50 years of MMWR at CDC. MMWR 2011;60(Suppl).
9. CDC. PulseNet. Atlanta, GA: Atlanta, GA: US Department of Health and
Human Services, CDC; 2011. Available at http://www.cdc.gov/pulsenet.
10. CDC. Multistate outbreak of Salmonella serotype Tennessee infections
associated with peanut butter—United States, 2006–2007. MMWR
2007;56:521–4.
11. CDC. Multiple-serotype Salmonella gastroenteritis outbreak after a
reception—Connecticut, 2009. MMWR 2010;59:1093–7.
12. Mason JO, McLean WR. Infectious hepatitis traced to the consumption
of raw oysters: an epidemiologic study. Am J Hyg 1962;75:90–111.
13. CDC. Respiratory infection—Pennsylvania, August 2, 1976. MMWR
1976;25:244.

26

MMWR  /  October 7, 2011  /  Vol. 60

14. CDC. Follow-up on respiratory illness—Pennsylvania. MMWR 1977;​
26:9–11.
15. Fraser DW, Tsai TR, Orenstein W, et al. Legionnaires’ disease: description
of an epidemic of pneumonia. N Engl J Med 1977;297:1189–97.
16. CDC. Outbreak of Salmonella serotype Saintpaul infections associated
with multiple raw produce items—United States, 2008. MMWR
2008;57:929–34.
17. Shaw FE, Goodman RA, Lindegren ML, Ward JW. A history of MMWR.
In: Public health then and now: celebrating 50 years of MMWR at CDC.
MMWR 2011;60(Suppl).
18. CDC. Epi-X: the epidemic information exchange. Atlanta, GA: US
Department of Health and Human Services; 2010. Available at http://
www.cdc.gov/epix.
19. Peterson AT, Bauer JT, Mills JN. Ecologic and geographic distribution
of filovirus disease. Emerg Infect Dis 2004;10:40–7.
20. CDC. Swine influenza A (H1N1) infection in two children—Southern
California, March–April 2009. MMWR 2009;58:400–2.

Supplement

Laboratory Contributions to Public Health
Walter R. Dowdle, PhD1
Leonard W. Mayer, PhD2
Karen K. Steinberg, PhD3
Neelam D. Ghiya, MPH4
Tanja Popovic, MD, PhD4
1Global Polio Eradication, Task Force for Global Health, Decatur, Georgia
2Division of Bacterial Diseases, National Center for Immunization and Respiratory Diseases, CDC, Atlanta, Georgia
3Division of Laboratory Sciences, National Center for Environmental Health, CDC, Atlanta, Georgia
4Office of the Associate Director for Science, Office of the Director, CDC, Atlanta, Georgia
Corresponding author: Walter R. Dowdle, PhD, Task Force for Global Health, 325 Swanton Way, Decatur, GA 30030; Telephone: 404-687-5608; Fax:
404-371-1087; E-mail: [email protected].

Introduction

The Public Health Laboratory of 1961

Alexander Langmuir, founder of the CDC Epidemic
Intelligence Service (EIS), was quoted in the early 1960s
instructing incoming EIS officers that the only need for the
laboratory in an outbreak investigation was to “prove their conclusions were right.” Understandably, this was not well received
by the CDC Laboratory Branch. However, Langmuir’s point
was not to denigrate the laboratory but to emphasize the power
of an investigation based on a solid clinical case definition and
established field epidemiologic principles. In truth, in 1960,
when CDC assumed responsibility for publishing MMWR, the
laboratory provided little added value in many investigations,
except to confirm “what the etiologic agent wasn’t.” Existing
diagnostic laboratory procedures for infectious and noninfectious diseases of public health importance were reasonably
reliable but basic and laborious. For diagnosis of many diseases and conditions, no laboratory procedures existed. Since
1961, advances in molecular sciences, analytical chemistry,
and technology have revolutionized the public health laboratory investigative capacity, capability, and specificity and have
emphasized the importance of more independent laboratory
research. The term “molecular epidemiology” is widely applied,
and the number of diseases for which laboratory diagnoses are
available today is substantially larger. This article describes the
principles and practices of the state-of-the-art public health
laboratory in 1961 and provides examples of scientific, technologic, and strategic advances since that time that characterize
the still evolving public health laboratory of the 21st century.
Browsing through MMWR, volume 10, week 1, January 13,
1961, provides insight into the public health laboratory of
1961 and the topics of most interest and visibility at that time.
Subsequently, progress and contributions made by the public
health laboratories are provided in a more detailed account by
using several illnesses and conditions of public health importance
as examples. They span both infectious and noninfectious arenas.
Some were listed in the first MMWR summary, but some were
not under consideration in 1961 or were yet to be discovered.

Poliomyelitis (3,190 cases in 1960) was the first disease
discussed in the Summary section of the January 13, 1961,
MMWR (1). The basic procedures for isolation and identification of polioviruses in cell cultures were slow but well
developed, benefitting from 30 years of concentrated laboratory research to understand the disease and develop a vaccine.
Week 33 published the Surgeon General’s announcement that
a license had been granted to Pfizer Inc. for the manufacture of
the Sabin live oral polio vaccine (OPV) type 1. This attenuated
strain was developed in the CDC laboratories in Montgomery,
Alabama. Although a remarkable humanitarian achievement,
the introduction of live vaccine into the environment and the
clinical and epidemiologic need to differentiate vaccine strains
from wild strains proved a major challenge to the laboratory.
Hepatitis was the second viral disease in the Summary
section. The national hepatitis epidemic occurred in 1961.
Shellfish were implicated for the first time. The laboratory
was of little help because the etiologic agents were unknown.
Outbreaks were differentiated into infectious or serum hepatitis
on the basis of clinical and epidemiologic grounds, and the
totals (72,651 cases in 1961) were combined.
Influenza A2 was the third disease noted in the Summary
section. Because development of an influenza virus vaccine
had been a high priority of the U.S. military during World
War II to avert another 1918 disaster, basic procedures for
virus isolation and serologic diagnoses were well established.
Classification according to H (hemagglutinin) and N (neuraminidase) antigens was yet to come.
Rabies was a notifiable disease in humans and animals,
with three and 3,599 cases reported, respectively, in 1961 (2).
Diagnostic procedures were evolving from the traditional histologic staining for Negri bodies to specific fluorescent antibody
staining, greatly increasing confidence in laboratory diagnosis.
Anthrax, commonly known as “wool-sorters disease,” totaled
14 cases in 1961 (2). The laboratory diagnosis of Bacillus
anthracis was based on traditional microbiologic methods,
MMWR  /  October 7, 2011  /  Vol. 60

27

Supplement

some of which are still the cornerstone of laboratory diagnostics
today: staining with the M’Fadyean polychrome methylene
blue stain (developed in 1903) and susceptibility to lysis by
the gamma phage (since 1951). Human vaccines for anthrax
had already been developed in the United Kingdom and the
United States. There were no prescribed special biosafety
laboratory facilities.
Outbreaks of salmonellosis, shigellosis, staphylococcal food
poisoning, pathogenic Escherichia coli, typhoid fever, and
botulism were commonly reported in volume 10, week 1.
Mingled among these reports were 25 apparent foodborne
disease outbreaks of unknown etiology by mid-year. The
need for discovery of new and more precise characterization
of already recognized etiologic agents of diarrhea was evident.
Listed clinical conditions of unproven etiology included
rubella, erythema infectiosum, and cat-scratch fever. Yet
to come were rotavirus, E. coli O157, and HIV infections;
Legionnaires disease; hemorrhagic fevers; and severe acute
respiratory syndrome, to name a few. Roseola infantum, now
known to be caused by one of eight human herpesviruses (type
6), exemplifies the progress made during the past 50 years.
Only one (herpes simplex virus) was recognized in 1961.
Except for one naturally occurring nicotinic acid (niacin)
toxin, MMWR contained no reports on noninfectious diseases. However, in 1961, CDC began a collaboration with
the National Heart, Lung, and Blood Institute to expand the
Cooperative Cholesterol Standardization Program with a goal
of standardizing cholesterol measurements and, ultimately,
decreasing deaths and disability from heart disease.
The following sections review these and other diseases and
provide some insight into the scientific and technical advances
that have revolutionized the public health laboratory capabilities during the past 50 years.

Poliomyelitis
The inability in 1961 to distinguish clearly between epidemic wild strains and attenuated OPV strains recovered from
fecal samples led to numerous disagreements among advisory
bodies on the etiology of potential cases of vaccine-associated
poliomyelitis. The biology-based laboratory test then in use
also figured prominently in the 1974 landmark legal ruling
(Reyes vs. Wyeth Laboratories) on the liability of the manufacturer for failure to warn the public of OPV risks (3), despite
the epidemiologic and biologic laboratory evidence that the
causative virus was most likely wild. More reliable nonbiologic
laboratory techniques were needed. By 1984, the laborious
but definitive newly developed oligonucleotide fingerprinting
technique confirmed the Reyes poliovirus isolate as wild (4).

28

MMWR  /  October 7, 2011  /  Vol. 60

The growing capabilities of the poliovirus laboratory coincided with the launch of the global polio eradication initiative
in 1988. Continuously evolving molecular techniques and
novel technologies eventually made possible the sequencing
and comparing of poliovirus genomes in real time. Linking
these advances to the newly established poliovirus evolutionary rate provided previously unimagined detailed information
about individual poliovirus isolates. In 2000, genome sequencing identified the first outbreak of circulating vaccine-derived
polioviruses, which continue to occur in areas with low rates
of OPV coverage and document the urgent need to replace live
with inactivated (killed) poliovirus vaccine (IPV) (5).
The 2010 MMWR report on polio eradication progress
illustrates current laboratory capabilities (6). The Islamabad,
Pakistan, polio laboratory, one of 147 laboratories in the polio
network, processed >15,000 fecal and sewage samples and isolated 137 polioviruses in 2009. Genomic sequencing of these
137 isolates from Afghanistan and Pakistan provided data that
identified virus origins, transmission zones of circulating wild
viruses, and viruses that were not closely related. Information
about virus origin and transmission inform the program of
inadequately immunized populations. Distantly related viruses
provide evidence of evolutionary gaps and inform the program
of surveillance weaknesses that must be improved. Molecular
epidemiology plays a key role in all aspects of the poliovirus
eradication initiative.

Hepatitis
In 1961, a report of an outbreak of infectious hepatitis A
among chimpanzee handlers (7) generated considerable interest, suggesting nonhuman primates might be possible models
for human hepatitis. However, 18 years would pass before the
virus would be propagated in cell culture, which would make
laboratory diagnosis and a vaccine possible (8). In 1963, the
serendipitous discovery of an antigen in human blood (9) led
to the eventual association of this protein with serum hepatitis
B and development of a highly effective vaccine in the early
1980s. The development of diagnostic tests for hepatitis A
and B viruses led to recognition of three other etiologic agents
(types C, D, and E). In few other infectious diseases has progress been as rapid and effects on disease reduction as dramatic.

Influenza
In 1961, lessons learned from the overwhelming laboratory workload during the A2 pandemic of 1957–58 were still
being implemented. Expanded serologic diagnostic tests were
being introduced for other newly recognized agents of acute

Supplement

respiratory disease (parainfluenza, respiratory syncytial virus,
and adenoviruses). The workhorse complement fixation (CF)
serologic test deserves special mention to illustrate the laborintense laboratory practices of the day. The test was performed
over a 3-day period in a large room with two big tables specially designed for the purpose in the new (1960) virology
laboratory building. The average run of paired serum samples
from 50 patients used approximately 4,000 test tubes (all to
be washed and reused), 60 wire test tube racks, and nearly
100 pipettes. On day 1, six antigens were prepared, test tubes
marked, and serum sequentially diluted (by mouth pipette).
On the morning of day 2, the four essential test reagents were
prepared and standardized. In the afternoon, 8–10 laboratory
personnel were rounded up; given instructions and pipettes;
and marched around the table adding one ingredient in precise
sequence. The racks were moved to a walk-in refrigerator. On
the morning of day 3, the final indicator reagent was added
and the results read, tube by tube, against the ceiling lights,
trusting no one had added materials to the wrong test tubes or
in the wrong sequence. Another 4 years would pass before that
resource-intensive CF procedure would be aided by microtechniques and, later, by automatic pipetting machines (Figure 1).
Today, the CF test is rarely employed, but other serologic tests
(neutralization and hemagglutination-inhibition), also used
in 1961 to detect and quantify antibodies in patient’s serum,
remain in principle unchanged. The greatest advances in understanding the influenza virus closely parallel the phenomenal
advances in molecular technology. Definitive characterization
FIGURE 1. Laboratorians reading and checking serologic tests to
determine presence of influenza A/NJ/8/76 (swine flu) and registering antibody rise to the swine influenza virus during vaccine testing
trials. 1976

Photo: CDC

of influenza viruses, as in all other areas of virology, relies heavily on genome sequencing. The pandemic virus of 1918 was
reconstructed by reverse genetics and genomic RNA recovered
from archived formalin-fixed lung autopsy materials and from
an influenza victim buried in the permafrost (10). The pandemic influenza A (H1N1) 2009 virus was demonstrated to be
a triple genetic reassortant with an antigenic structure similar
to those of the influenza viruses circulating early in the 20th
century (11). Yet to benefit from these major breakthroughs
in science is the killed influenza vaccine, which has seen only
incremental improvements since 1961.

Anthrax
Major advances in the laboratory identification of B. anthracis were made during the 1980s by sequencing the structural
genes located on one of the plasmids, pXO1, and encoding the
three anthrax toxins (12). However, the real scientific renaissance of B. anthracis began in the mid-1990s as inhalation
anthrax became the initial focus of the laboratory component
of biothreat preparedness in the United States. Development
of new diagnostic and molecular subtyping tools with emphasis
on standardization and quality control led the path for establishing the Laboratory Response Network that was instrumental in analyzing approximately 200,000 environmental
and clinical specimens during the 2001 anthrax attacks (13).
Polymerase chain reaction (PCR) detecting three B. anthracis–
specific loci allowed for rapid (a few hours) identification of
this organism directly from clinical specimens. Multiple locus
variable-number-of-tandem-repeat analysis (MLVA) made differentiating the B. anthracis strain and implicating the Ames
strain in 2001 possible. Identification of an identical MLVA
type in the clinical specimens of the patients and at their respective infection sources (e.g., offices, post offices) provided the
laboratory confirmation that the events were intentional and
not a result of natural exposure (14).
Laboratory research on B. anthracis continues post 2001.
Although the first report of naturally occurring anthrax toxin
genes in a species (B. cereus) other than B. anthracis adds
complexity to the identification process, it also emphasizes
the importance of vigilance and close collaboration between
those treating the patients, the public health community, and
the research community in ensuring that the true causative
agents are identified rapidly and reliably (15).
Rapid detection in clinical specimens and molecular subtyping of biothreat agents, which were demonstrated to be
of critical importance for public health response in 2001, are
now the standard in approximately 150 Laboratory Response
Network laboratories in the United States and worldwide.

MMWR  /  October 7, 2011  /  Vol. 60

29

Supplement

This ancient disease is likely to continue to shape research and
public health future issues.

Foodborne Diseases (PulseNet)
Methods for characterizing etiologic agents of diarrhea,
such as multilocus enzyme electrophoresis and ribotyping,
first became available and used during the 1980s. However,
no method was broadly accepted and standardized for use on
different organisms until after the E. coli experience of the
early 1990s.
From November 1992 through February 1993, approximately 700 laboratory-confirmed infections with E. coli
O157:H7 occurred in Washington, Idaho, California, and
Nevada associated with ground beef. Distinct clinical presentation associated with this pathogen was first described in
1983 and subsequently recognized as an important cause of
bloody diarrhea and the most common cause of renal failure
in children (hemolytic uremic syndrome) (16). During the
1992–93 outbreak investigations, CDC used pulsed-field gel
electrophoresis (PFGE) to characterize clinical and food isolates
and distinguish outbreak-related and nonoutbreak strains (17).
To satisfy the subsequent enormous nationwide demand for
PFGE subtyping, standardized methodology was transferred
to four state public health laboratories in 1995. This national
molecular subtyping network for foodborne disease surveillance later became known as PulseNet (18) and was officially
launched in 1998 by the White House.
PFGE continued to be an indispensable tool in a number
of E. coli O157 outbreaks. Over time, the primary role of
PFGE and PulseNet gradually shifted from a tool to investigate and compare outbreaks to a real-time surveillance,
cluster-detection, and outbreak investigation system. One such
PulseNet-detected outbreak in Colorado in 1997 resulted in the
largest meat recall thus far (19). PulseNet quickly expanded to
include other etiologic agents of foodborne diseases: Salmonella
and Shigella spp, Listeria monocytogenes, Campylobacter jejuni,
Vibrio cholerae, and Yersinia pestis (www.cdc.gov/pulsenet) and
has gone on to receive awards as one of the most innovative
government programs.
The impact of PulseNet on the nation’s health has been
enormous. PulseNet has been instrumental in improving
foodborne disease surveillance and outbreak investigations,
especially outbreaks in which the cause might be the same
but affected persons are geographically far apart. Outbreaks
and their causes now can be identified much faster. Critically
important is the PulseNet approach to building public health
infrastructure in state and local health departments with
methods, equipment, and training that can be used broadly.

30

MMWR  /  October 7, 2011  /  Vol. 60

Geographically localized outbreaks are no longer the norm.
Foodborne illnesses do not respect borders. Food distribution,
preparation, and consumption practices have changed worldwide during the past few decades so that food produced and
prepared in one place can be sold and consumed worldwide.
Consequently, PulseNet International, a network of national
and regional laboratories, was created to track foodborne infections worldwide. Each laboratory uses standardized methods
and shares the information within the network in real time.
PulseNet is committed to introducing new and improved
subtyping methods and strengthening collaboration with the
food industry to prevent outbreaks.
At the time of the first MMWR publication at CDC in
1961, little was known about viral agents as causes of enteric
diseases. Soon thereafter a number of viruses were identified,
detected in patients’ fecal specimens, and associated with
clinical symptoms: during the 1960s, enteric adenoviruses and
Norwalk virus (presently defined as noroviruses and belonging, along with the saporovirues, in the Caliciviridae family)
and in the 1970s rotaviruses, caliciviruses, and astroviruses
(20). Today, noroviruses are recognized as the most important
causes of nonbacterial epidemics of gastroenteritis; rotaviruses
account for almost one third of all diarrhea-related deaths in
children aged <5 years worldwide; and since 2006, two new safe
rotavirus vaccines have been licensed. Feces remains the main
clinical sample, and available laboratory diagnostic tests range
from isolation of viruses in cell culture to direct visualization
of viruses in clinical specimens (e.g., electron microscopy) to
detection of viral antigens (e.g., enzyme-linked immunosorbent assay) to detection of viral nucleic acid (e.g., PCR).

Legionnaires Disease
In July 1976, the disease became a household word when
approximately 200 American Legion conventioneers in
Philadelphia were stricken, resulting in 34 fatalities (21).
Initial media speculation focused on swine influenza, which
had caused an outbreak in Fort Dix, New Jersey, and media
excitement earlier in the year. An extensive epidemiologic
investigation indicated airborne transmission of an agent
in the environment, but the inability of the state and CDC
laboratories to identify quickly an infectious etiologic agent
intensified media attention and speculation about other
sources, including heavy metals or other poisons such as
paraquat and even terrorism. During fall 1976, a team of
nationally recognized pathologists visited CDC and reviewed
clinical findings, autopsy materials, and tissue sections and
concluded the causative agent could be a virus or a toxin but
not a bacterium, illustrating the pitfalls of using conventional

Supplement

techniques to identify an unknown, unconventional agent. In
December 1976, CDC identified the agent as a bacterium that
could not be detected by using ordinary tissue staining (22)
(Figure 2). Tissues from Guinea pigs inoculated with patient
specimens showed small pleomorphic rods by fluorescent antibody staining by using convalescent serum. The bacteria were
initially grown in eggs injected with tissue from Guinea pigs
and eventually on microbiologic media, allowing production
of reasonable amounts of materials for other studies.
The initial reports and presentations by CDC describing
the etiologic agent were met with considerable skepticism and
disbelief, but the etiology and the name Legionella pneumophila
became accepted as outbreaks were reported by others. The
identification of L. pneumophila as a new species of bacteria
was determined by using DNA–DNA hybridization (23).
Today, the genus Legionella contains 48 species, 20 of which
have been shown to cause human disease.
Outbreaks occurring as early as 1957 were retrospectively
associated with serologic evidence of Legionnaires disease (or
legionellosis). After L. pneumophila was identified and this
bacterium was delineated as a common cause of pneumonia,
several outbreaks have occured around the world, some as large
as 800 cases. Retrospective examples of legionellosis include an
outbreak of pneumonia among patients of the St. Elizabeth’s
Psychiatric Hospital, Washington, D.C., during 1965 with 94
cases and 16 deaths. Another form of this disease was shown
in visitors to and employees of the Pontiac, Michigan, health
department in 1968 with 144 cases of fever, headache, myalgia, and fatigue without pneumonia, resulting in no fatalities
(24). In addition to these serologic investigations that used
microbiologic analysis of bacteria stored at CDC, an unclassified agent isolated in 1947, was shown to be identical to
L. pneumophila by serologic, cultural, and DNA relatedness
studies. In these situations, the maintaining of large patient
specimen collections, serum banks, and culture collections was
shown to be of great value.
Although the bacterium is widespread in many freshwater
environments, the disease is usually associated with humanmade water systems, such as cooling towers, air conditioning,
fountains, spa baths, and water supply systems of buildings
(including showers). Although culture remains the standard,
PCR is increasingly used to detect Legionella spp. (25).
Understanding the modes of transmission and epidemiology of
legionellosis has resulted in major changes in construction and
maintenance recommendations for municipal, commercial,
and residential water systems.

FIGURE 2. Dr. Joseph E. McDade (left), and Dr. Charles C. Shepard,
working with a microscope in CDC’s leprosy and Rickettsia
laboratories in 1977. On January 14, 1977, they isolated the agent
that had caused the Legionnaires outbreak

Photo: CDC

Noninfectious Diseases
The inaugural CDC MMWR volume was devoted almost
exclusively to infectious diseases. Even at the time, however,
CDC and other laboratories were engaged in noninfectious
disease research that would make major contributions to
the identification and prevention of chronic, newborn, and
environmental diseases and conditions. Examples include 1)
standardizing cholesterol measurements that enabled longitudinal studies to establish the causal link between cholesterol
levels and cardiovascular disease (CVD); 2) identifying lead
in gasoline as a major source of lead exposure for children and
adults; 3) characterizing exposure to tobacco smoke and its
toxic constituents in smokers and nonsmokers; and 4) developing methods and providing quality assurance for screening
for conditions and diseases of newborns.
CVD remains the leading cause of death in the United States,
with reduction of low-density lipoprotein (“bad”) cholesterol
a major public health priority to prevent CVD and death
(26) (Figure 3). In 1957, CDC began collaboration with
the National Heart, Lung and Blood Institute to develop a
standardization program for total cholesterol measurements.
The initial program, called the Cooperative Cholesterol
Standardization Program, was later expanded to include triglycerides and high-density lipoprotein (“good”) cholesterol and
renamed the Lipid Standardization Program. These programs
had a goal of standardizing lipid and lipoprotein measurements
and, ultimately, decreasing deaths and disability from heart
disease (27). CDC’s cholesterol reference method has served as
the standard for cholesterol testing for approximately 35 years

MMWR  /  October 7, 2011  /  Vol. 60

31

Supplement

FIGURE 3. A laboratorian using a manual method for conducting a
cholesterol determination. 1966

Photo: CDC

and was essential to provide the accuracy base for cholesterol
measurements in the major epidemiologic studies and clinical trials that established the relationship between cholesterol
concentrations and risk for CVD (28). In addition to the Lipid
Standardization Program, CDC continues to standardize a
network of five laboratories that use the CDC accuracy base to
calibrate measurement of high-density liproprotein cholesterol,
low-density liproprotein cholesterol, and total cholesterol by
commercial instrumentation in the clinical laboratories that
measure the lipid levels of Americans.
Lead exposure is one of the oldest known environmental
and occupational hazards, but not until the early 1970s was
relatively low-level exposure recognized to cause neurodevelopmental impairment in children (29). Using highly precise and
accurate atomic absorption methods, CDC measured blood
lead levels in the U.S. population as a component of CDC’s
National Health and Nutrition Examination Surveys during
1976–1980 (30) and identified lead in gasoline as a major

32

MMWR  /  October 7, 2011  /  Vol. 60

exposure source for children and adults. This new and unexpected finding was a major factor in the U.S. Environmental
Protection Agency’s decision to remove lead from gasoline, an
effort that has been cited as one of the most important accomplishments of public health (31). Accurate blood lead measurements in the National Health and Nutrition Examination
Surveys documented that the removal of lead from gasoline
resulted in a >90% decrease in the percentage of children with
blood lead levels ≥10 µg/dL, the current level of health concern
(32,33). These data supported removal of lead from gasoline
in industrialized nations around the world, resulting in similar
reductions in lead exposure.
Development of methods to quantify approximately 100
addictive and toxic constituents of tobacco products led to
an especially sensitive and accurate measurement for serum
cotinine to quantify tobacco smoke exposure in smokers and
to nonsmokers exposed to secondhand smoke. Evidence that
88% of nonsmokers were exposed to secondhand smoke was
used during the early 1990s to justify restricting smoking in
public places and in the workplace (34). Follow-up of cotinine
measurements documented the reduction in average cotinine
levels for nonsmokers by approximately 70% (34). CDC
measurements of addictive and toxic constituents of tobacco
products, including tobacco-specific carcinogens, are the major
science underpinnings for regulation of tobacco products.
CDC standardizes diagnostic methods for >50 diseases of
newborns, ensuring the quality of measurements performed on
heel-stick blood spot specimens from >98% of all babies born
each year in the United States. Laboratory measurements for
early diagnosis usually lead to effective early treatment of many
diseases, including congenital hypothyroidism, congenital
toxoplasmosis, galactosemia, congenital adrenal hyperplasia,
sickle cell disease, maternal HIV infection, cystic fibrosis, fatty
acid oxidation disorders, and amino acid disorders.
CDC characterizes exposure of the U.S. population and vulnerable population groups to environmental chemicals known
or suspected to cause health problems (35). CDC can currently
measure 396 environmental chemicals in blood or urine—with
future plans to expand to more than 500. Studies of human
exposure and health effects particularly benefit from CDC
blood and urine measurements of these chemicals. In addition,
to bolster emergency response for chemical and radiologic terrorism, CDC has developed capability to measure, in blood
or urine, 150 chemical agents and nine radionuclides that are
priority terrorism agents. Future plans include expansion of
these capabilities, with special focus on measuring additional
radionuclides.

Supplement

The Public Health Laboratory
of the Future
The disease triangle is the basic tenet for causation of
infectious disease representing the interaction between three
entities: environment, pathogen, and host. Chronic diseases
are generally caused by the interaction of host factors and the
environment, including lifestyle factors and diet, with pathogens sometimes playing a causative role—for example, human
papillomavirus linked to cervical cancer and Helicobacter pylori
linked to the development of duodenal and gastric ulcers and
stomach cancer. Advances in laboratory sciences, including
informatics and bioinformatics, molecular biology and genomics, nanotechnology and technologies yet to come will facilitate
understanding of causation and epidemiology of infectious and
chronic diseases that threaten the public’s health.
Enormous progress has been made since the central dogma
of molecular biology (DNA to RNA to protein) was elucidated
some 50 years ago, and revised in 1970 with the discovery of
reverse transcription (36). Many new “-omics have appeared,”
including genomics, proteomics, glycomics, metabalomics,
and, transcriptomics. A Google search yielded about 60 million results for the term genome (37) alone. The development
of the PCR, for which Kerry Mullis won a Nobel Prize in
1993, made sequencing the human and other genomes feasible (38). Soon, single-molecule DNA sequencing will make
it possible to envision whole genomes, including the human
genome, to be sequenced in 1 day at a cost of <$1,000 (39).
Bioinformatics has made it possible to exploit these techniques,
generate algorithms, and rapidly analyze complex laboratory
and epidemiologic databases to identify virulence factors in
infectious diseases and detect biomarkers at the earliest stages
when diseases can be reliably predicted and prevented.
The laboratory of the future will build on the work being
done today in miniaturization and nanotechnology, considered
to be the third industrial revolution. Miniaturization of laboratory instruments at the point-of-care will allow public health
workers to obtain patient data in remote places. Ultrasensitive
immunosensors and arrays based on nanotechnology will have
the ability to quantify protein concentrations at the level below
micrograms/deciliter (40). Urinary tract infections will be
identified at the bedside in remote regions with miniaturized
electrochemical biosensors (41).
Continued advances in laboratory science and informatics are
critically important for all aspects of public health, especially
for public health surveillance where informatics is essential
for defining the baseline information about human health
and for evaluating progress. However, care must be taken
that the application of newer laboratory techniques and more

sophisticated health informatics introduced for the good of
public health do not also bring unintended harm. Society must
judge the ethics of implementing the scientifically possible,
whether it is the personal risk of the use of nanoparticles or
the privacy risk of placing a patient’s genome in an electronic
record.

Conclusions
Enormous advances have been made in the public health
laboratory in the past 50 years, greatly expanding disease
knowledge, revolutionizing diagnostic and surveillance relevance and capacity, and facilitating appropriate control strategies. From limited biologic capabilities, today’s public health
laboratory routinely uses a multitude of molecular technologies
and electronic applications. From a small number of laboratories with primarily an infectious disease focus, today’s public
health laboratory is responsible for emergency preparedness
and response, environmental health, food safety, global health,
infectious diseases, informatics, laboratory systems and standards, genetics and newborn screening, and research. From a
narrow local, state, or national perspective, today’s public health
laboratories are recognized as essential components of a vital
national and global surveillance system. The next 50 years are
anticipated to be equally exciting and the young public health
practitioners will see and benefit from this progress.
References
1. CDC. Provisional information on selected notifiable diseases in the
United States and on deaths in selected cities for week ended January 7,
1961. MMWR 1961;10:2.
2. CDC. Reported incidence of notifiable diseases in the United States,
1961. MMWR 1962;11(Suppl).
3. Mann ME. Mass immunization cases: drug manufacturers’ liability for
failure to warn. Vanderbilt Law Review 1976;29:235–66.
4. Kew OM, Nottay BK. Molecular epidemiology of polioviruses. Rev
Infect Dis 1984;6:499–504.
5. Kew OM, Sutter RW, de Gourville EM, Dowdle WR, Pallansch MA.
Vaccine-derived polioviruses and the endgame strategy for global polio
eradication. Annu Rev Microbiol 2005;59:587–635.
6. CDC. Progress toward poliomyelitis eradication—Afghanistan and
Pakistan, 2009. MMWR 2010;59:268–72.
7. Hillis WD. An outbreak of infectious hepatitis among chimpanzee
handlers at a United States Air Force base. Am J Hyg 1961;73:316–28.
8. Provost PJ, Hilleman MR. Propagation of human hepatitis A virus in
cell culture in vitro. Proc Soc Exp Biol Med 1979;160:213–21.
9. Alter HJ, Bloomberg BS. Further studies on a “new” human isoprecipitin
system (Australian antigen). Blood 1966;27:297–309.
10. Tumpey TM, Basler CF, Aguilar PV, et al. Characterization of the
reconstructed 1918 Spanish influenza pandemic virus. Science
2005;310:77–80.
11. Xu R, Ekiert DC, Krause JS, Crowe JE Jr, Wilson IA. Structural basis
of preexisting immunity to the 2009 H1N1 pandemic influenza virus.
Science 2010;328:357–60.
12. Mock M, Fouet A. Anthrax. Annu Rev Microbiol 2001;55:647–71.

MMWR  /  October 7, 2011  /  Vol. 60

33

Supplement

13. Jernigan DB, Raghunathan PL, Bell BP, et al. Investigation of
bioterrorism-related anthrax, United States, 2001: epidemiologic
findings. Emerg Infect Dis 2002;8:1019–28.
14. Hoffmaster AR, Fitzgerald CC, Ribot E, Mayer LW, Popovic T. Molecular
subtyping of Bacillus anthracis and the 2001 bioterrorism-associated
anthrax outbreak, United States. Emerg Infect Dis 2002;8:1111–6.
15. Hoffmaster AR, Ravel J, Rasko DA, et al. Identification of anthrax toxin
genes in a Bacillus cereus associated with an illness resembling inhalation
anthrax. Proc Natl Acad Sci USA 2004;191:8449–54.
16. CDC. Update: multistate outbreak of Escherichia coli O157:H7
infections form hamburgers—western United States, 1992–1993.
MMWR 1993;42:258–63.
17 Barrett TJ, Lior H, Green JH, et al. Laboratory investigation of a
multistate food-borne outbreak of Escherichia coli O157:H7 by using
pulsed-field gel electrophoresis and phage typing. J Clin Microbiol
1994;32:3013–7.
18. Swaminathan B, Barrett TJ, Hunter SB, Tauxe RV; CDC PulseNet Task
Force. PulseNet: the molecular subtyping network for foodborne
bacterial disease surveillance, United States. Emerg Infect Dis
2001;7:382–9.
19. CDC. Escherichia coli O157:H7 infections associated with eating a
nationally distributed commercial brand of frozen ground beef patties
and burgers—Colorado, 1997. MMWR 1997;46:777–8.
20. Christensen ML. Human viral gastroenteritis. Clin Microbiol Rev
1989;2:51–89.
21. Fraser DW, Tsai TR, Orenstein W, et al. Legionnaires’ disease: description
of an epidemic of pneumonia. N Engl J Med 1977;297:1189–97.
22. McDade JE, Shepard CC, Fraser DW, Tsai TR, Redus MA, Dowdle
WR. Legionnaires’ disease: isolation of a bacterium and demonstration
of its role in other respiratory disease. N Engl J Med 1977;297:​
1197–203.
23. Brenner DJ, Steigerwalt AG, McDade JE. Classification of the
Legionnaires’ disease bacterium: Legionella pneumophilia, genus novum,
species nova, of the family Legionellaceae, familia nova. Ann Intern Med
1979;90:656–8.
24. Kaufmann AF, McDade JE, Patton CM, et al. Pontiac fever: isolation
of the etiologic agent (Legionella pneumophilia) and demonstration of
its mode of transmission. Am J Epidemiol 1981;114:337–47.
25. Fields BS, Benson RF, Besser RE. Legionella and Legionnaires’ disease:
25 years of investigation. Clin Microbiol Rev 2002;15:506–26.
26. Xu J, Kochanek KD, Murphy SL, Tejada-Vera B; Division of Vital
Statistics. Deaths: final data for 2007. Natl Vital Stat Rep
2010;58:1–72.

34

MMWR  /  October 7, 2011  /  Vol. 60

27. Rifai N, Cooper GR, Brown WV, et al. Clinical Chemistry journal has
contributed to process in lipid and lipoprotein testing for fifty years.
Clin Chem 2004;50:1861–70.
28. Myers GL, Kimberly MM, Waymack PP, Smith SJ, Cooper GR, Sampson
EJ. A reference method laboratory network for cholesterol: a model for
standardization and improvement of clinical laboratory measurements.
Clin Chem 2000;46:1762–72.
29. Bellinger DC, Bellinger AM. Childhood lead poisoning: the torturous
path from science to policy. J Clin Invest 2006;116:853–7.
30. Pirkle JL, Brody DJ, Gunter EW, et al. The decline in blood lead levels
in the United States. The National Health and Nutrition Examination
Surveys (NHANES). JAMA 1994;272:284–91.
31. Pirkle JL, Kaufmann RB, Brody DJ, Hickman T, Gunter EW, Paschal
DC. Exposure of the U.S. population to lead, 1991–1994. Environ
Health Perspect 1998;11:745–50.
32. CDC. Blood lead levels—United States, 1999–2002. MMWR
2005;54:513–6.
33. Jones RL, Homa DM, Meyer PA, et al. Trends in blood lead levels and
blood lead testing among US children aged 1 to 5 years, 1988–2004.
Pediatrics 2009;123:e376–85.
34. Pirkle JL, Flegal KM, Bernert, JT, Brody DJ, Etzel RA, Maurer KR.
Exposure of the US population to environmental tobacco smoke: the
Third National Health and Nutrition Examination Survey, 1988 to
1991. JAMA 1996;275:1233–40.
35. CDC. Fourth national report on human exposure to environmental
chemicals. Available at http://www.cdc.gov/exposurereport/. Accessed
August 10, 2010.
36. Temin HM, Mizutani S. RNA-dependent DNA polymerase in virions
of Rous sarcoma virus. Nature 1970;226:1211–3.
37. National Center for Biotechnology Information, GenBank statistics.
Growth of GenBank (1982–2008). Available at http://www.ncbi.nlm.
nih.gov/genbank/genbankstats.html. Accessed August 10, 2010.
38. Mullis K, Faloona F, Scharf S, Saiki R, Horn G, Erlich H. Specific
enzymatic amplification of DNA in vitro: the polymerase chain reaction.
Cold Spring Harb Symp Quant Biol 1986;51(Pt 1):263–73.
39. Efcavitch JW, Thompson JF. Single-molecule DNA analysis. Annu Rev
Anal Chem 2010;3:109–28.
40. Rushing JF, Kumar CV, Gutkind JS, Patel V. Measurement of biomarker
proteins for point-of-care early detection and monitoring of cancer.
Analyst 2010. Epub 2010.
41. Pan Y, Sonn GA, Sin NL, et al. Electrochemical immunosensor detection
of urinary lactoferrin in clinical samples for urinary tract infection
diagnosis. Biosens Bioelectron 2010. Epub 2010 Jul 8.

Supplement

History of Statistics in Public Health at CDC, 1960–2010:
the Rise of Statistical Evidence
Donna F. Stroup, PhD1
Rob Lyerla, PhD2
1Data for Solutions, Inc., Decatur, Georgia
2Office of the Global AIDS Coordinator, US Department of State
Corresponding author: Donna F. Stroup, PhD, Data for Solutions, Inc., Post Office Box 894, Decatur, GA 30031-0894; Telephone: 404-218-0841; Fax:
404-377-9696; E-mail: [email protected].

‘‘A … firm grasp of the statistical method was as essential part of the outfit of the investigator in
that field [epidemiology] as was a grounding in bacteriology.”—Anonymous, 1913 (1)

Introduction

The 1960s

It is difficult for us to imagine the report of an epidemiologic
investigation without at least one 2×2 table, p value, or odds
ratio. We now recognize that an understanding of mathematical
methods and the use of statistics to assess data in epidemiology and public health are critical for identifying the causes of
disease, modes of transmission, appropriate control and prevention measures, and for prioritizing and evaluating activities.
When CDC was established in 1946 (as the Communicable
Disease Center), the U.S. Public Health Service borrowed statistical methods developed by Florence Nightingale and Edwin
Chadwick, who had applied these techniques to implement
sanitary measures in London (2). Based on William Farr’s use
of statistical induction to analyze death rates (3), Karl Pearson’s
creation of goodness-of-fit tests and correlation methods, and
Bradford Hill’s development of guidelines for establishing
causal relationships (4), Nightingale employed statistics in
her efforts to reform the British military health-care system
through the founding of training programs and definition of
sound professional standards (5).
During the 1950s, CDC’s activities emphasized the work
of sanitarians and laboratory scientists, and the analytic
component of most epidemiologic investigations rarely went
beyond descriptive analysis and 2×2 tables. However, with
the establishment of the Epidemic Intelligence Service (EIS),
rapid response to outbreak investigations, and involvement of
mathematical experts, epidemiologic methods advanced (6).
Case-control studies were used routinely by EIS officers. An
investigation of Staphylococcus in a newborn nursery was the
first CDC report to include a chi-square statistic and a p value
(CDC, unpublished data, 1957). By the middle of the decade,
an early dose-response analysis was included in an investigation of hepatitis in a housing project (CDC, unpublished
data, 1956).

With the acquisition of MMWR in 1961 under Alexander
Langmuir’s leadership, CDC had a vehicle for influencing
the practice of biostatistics. Langmuir’s training under Wade
Hampton Frost, the first professor of epidemiology in the
United States at the Johns Hopkins University School of
Hygiene and Public Health, led to Langmuir’s emphasis on
quantitative foundations for public health and the need to link
data acquisition with practical application through the practice
of public health surveillance (7).
During this decade, the first t test in an epidemic-assistance
investigation (Epi-Aid) is found in Carl Norden’s report of
infectious mononucleosis in Kentucky (CDC, unpublished
data, 1963). The first pie chart appears in James Bryan and Ron
Roberto’s Epi-Aid for suspected poliomyelitis in the Marshall
Islands (CDC, unpublished data, 1963). During this period,
the vast majority of requests for Epi-Aids collected data through
convenience survey methods or used existing surveillance data.
In only two of 502 Epi-Aids was the method of randomization
reported. Calculations were restricted to those that could be
done by hand or later on programmable calculators (Figure 1).
Eventually, however, surveillance and other data analyses used
mainframe computers and the punched card throughout the
late 1960s.

The 1970s
In 1970, the Communicable Disease Center’s name changed
to the Center for Disease Control. Beyond semantics, this represented a broadening of the mission beyond communicable
diseases. In 1971, the National Center for Health Statistics
(not yet part of CDC) conducted the first National Health
Assessment and Nutrition Examination Survey (NHANES).
The National Institute for Occupational Safety and Health

MMWR  /  October 7, 2011  /  Vol. 60

35

Supplement

FIGURE 1. Statistician at CDC using MonroMatic desktop calculator,
Model 8N-213. circa 1958

program, the Epidemiologic Analysis System, which was an
early forerunner of Epi Info™, a suite of lightweight software
tools for use in field epidemiology first released by CDC in
1985 (see below).

The 1980s

Photo: CDC

joined CDC in 1973 and brought use of methods for noninfectious conditions, such as large population-based studies.
This expansion of activity to environmental and occupational
problems brought expanded opportunities for the contribution of statistical and engineering methods to public health.
One example is the use of NHANES data combined with data
on lead in gasoline from the U.S. Environmental Protection
Agency to develop a model to predict human blood lead levels
(8). The results were used to provide evidence that subsequently
led to a ban on the use of lead in gasoline in the United States.
In 1974, CDC assumed leadership of a major national
immunization campaign. Although the theory behind herd
immunity was developed during the 1920s, the development
of vaccines coupled with advances in mathematical modeling in
epidemiology found a new synergy in a paper written in 1971
(9). Four years earlier, in 1967, the World Health Organization
had declared its intent to eradicate smallpox within 10 years,
and the U.S. Public Health Service had declared its intent to
eliminate measles from the United States within 1 year (10).
Both of these tasks were theoretically to be achieved by the
induction of herd immunity with vaccines.
The year 1976 saw the beginning of flexible computing in
public health. To address the swine flu crisis (11), an auditorium at CDC was filled with epidemiologists and a Digital
Equipment PDP 11 minicomputer the size of a large refrigerator. A program called SOCRATES, written in FORTRAN,
allowed an epidemiologist to define questions, enter data, and
summarize the results in tabular form without the aid of a
programmer or a trip across campus to a mainframe computer.
The SOCRATES program later formed the basis of another

36

MMWR  /  October 7, 2011  /  Vol. 60

In the 1980s, public health saw an expansion of emphasis on
statistical methods and more statistical sophistication among
epidemiologists and analysts. The computer-punched card
was gradually replaced as the primary means for data storage by magnetic tape, as better computers became available
(Figure 2). Punched cards were still commonly used for data
entry and programming at CDC until the mid-1980s, when
the combination of lower-cost magnetic disk storage and
affordable interactive terminals on less expensive minicomputers made punched cards obsolete. However, their influence
persists through many standard conventions and file formats.
For example, the terminals that replaced the mainframe card
readers displayed 80 columns of text, the same amount of space
on the punched card.
The first report in MMWR containing results from a logistic regression model appeared in 1982, only 3 years after the
software package BMDP provided the LOGIT routine as part
of its software (12). In this investigation of typhoid fever in
Michigan, the model was unable to identify risk associated
with any food item because of a small number of cases and
little variation in food-consumption patterns. Since this first
use, logistic regression has become a standard technique in
public health and has contributed to policy formulation in
FIGURE 2. Computer workstation at CDC, 1980s

Photo: CDC

Supplement

many areas. For example, the results from a logistic regression
analysis were used to implement a requirement that tobaccocontrol programs should include opportunities for community
participation and interaction for maximal impact. (13).
In the early 1980s, CDC launched a major case-control
study as part of the nascent investigation of human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome
(AIDS) (14), which provided a platform for development of
new statistical methods for surveillance and estimation of
disease incubation periods (15). A major challenge for HIV/
AIDS surveillance was poor data quality due to underreporting,
reporting delay (16), and risk redistribution (17). To address
these problems, statistical scientists adapted methods from
correlation analysis (18) and developed a technique known as
back-calculation (19).
Back-calculation uses the number of AIDS cases diagnosed
per month or calendar quarter (which can be estimated from
AIDS surveillance data) and the probability distribution of the
incubation period (the time from HIV infection to diagnosis of
AIDS) to estimate the number of persons infected with HIV.
This incubation distribution must be estimated from cohort
studies. On the basis of these data, back-calculation methods
provide estimates of the number of persons infected with HIV
during each month or calendar quarter necessary to account
for the number of persons in whom AIDS has been diagnosed
during those same periods. The number of persons in whom
AIDS will be diagnosed in the future can then be projected
from the estimated HIV epidemic curve and the incubation
period distribution (20).
The back calculation method proved useful in navigating
two major changes in the way HIV/AIDS surveillance was
conducted. One was a 1993 change in the surveillance case
definition for AIDS to include all HIV-infected persons who
have <200 CD4+ T-lymphocytes/µL or a CD4+ T-lymphocyte
percentage of total lymphocytes <14, or in whom pulmonary
tuberculosis, invasive cervical cancer, or recurrent pneumonia
has been diagnosed (21). The other was the development and
widespread use of pharmacotherapy (zidovudine) (22). These
and other statistical challenges in HIV/AIDS surveillance
illustrated well the ability of statistical methods to respond to
developing public health problems.
During the mid-1980s, with the increasing availability of
microcomputers, CDC epidemiologists first began using computers during field investigations, but no user-friendly software
existed for the purpose. To remedy this problem, in the early
1980s, CDC began development of Epi Info, a general-purpose
computer program that could be used for epidemic investigations and surveillance (Table). Early versions of Epi Info were
used in field investigations on large “luggable” computers (23)

(Figure 3). The widespread distribution of Epi Info and the
responsiveness of its developers to the needs of epidemiologists
in the field drove the application of statistical methods in field
investigations throughout the world (24). A recent search of
MEDLINE found >23,000 citations mentioning Epi Info in
the peer-reviewed literature. Add to this countless other citations in reports not indexed, and the impact of its development
on the field of statistics is apparent. In addition, Epi Info aided
in early efforts to coordinate surveillance activities to reduce
the workload of state health departments (25).
During this period, statistical methods for surveillance also
advanced. The availability of methods of forecasting by using
time series methods augmented previous regression results
(26,27). An investigation in response to food poisoning in
Peru was the first documented field investigation to implement a time series analysis (CDC, unpublished data, 1986).
Use of these methods, developed during the 1920s, was aided
by the availability of computers that allowed computations to
be conducted in a reasonable amount of time.
More broadly, methods were developed to investigate
changes in patterns of surveillance data to aid in epidemic
detection and control (28). This development was further
aided in 1987, when the National Center for Health Statistics
became part of CDC and brought its expertise in vital statistics
and surveys (29).

The 1990s
Innovations continued during the 1990s in such areas as
the detection of statistical aberrations, and changes in patterns
of data reported over time (30–33). A 1988 Symposium on
Statistics in Surveillance (34) became the foundation for ongoing CDC symposia on the statistics of cluster investigations
(35), statistics for rare events and small areas (36), statistics as a
basis for public health decisions (37), emerging statistical issues
(38), complicated designs and data structures (39), methods for
decisions in uncertainty (40), methods for addressing health
inequities (41), and use of multisource data (42). Over time,
these symposia were accompanied by short courses to educate
the public health community about statistical methods (43). In
addition, CDC began giving awards for outstanding statistical
work that had public health impact (Figure 4).
Despite considerable achievements in reducing smoking
prevalence as the 20th century closed, tobacco use remained
responsible for one of every five U.S. deaths. In 1999, CDC’s
Office on Smoking and Health created the National Tobacco
Control Program to encourage coordinated efforts to reduce
tobacco-related diseases and deaths (44). The National Youth
Tobacco Survey measured the tobacco-related beliefs, attitudes,

MMWR  /  October 7, 2011  /  Vol. 60

37

Supplement

TABLE. Examples of software systems developed by CDC in the 1980s and 1990s
Sofware system name

Primary use

IDEAS (Interactive Data Entry and
Analysis System)

Reference

Support hospitals’ participation in CDC’s
nosocomial infection surveillance activities

Horan TC, White JW, Jarvis WR, et al. Nosocomial infection surveillance,
1984. MMWR 1986;35(No. SS-1).

SAMEC (Smoking-Attributable Mortality Allow states and local areas to estimate the
and Economic Costs)
impact of smoking-attributable illness and
mortality

CDC. State-specific estimates of smoking-attributable mortality and
years of potential life lost—United States, 1985. MMWR
1988;37:689–93.

Software for Congenital Syphilis
Surveillance

Assist states in reporting cases of
congenital syphilis

Dunn RA, Webster LA, Nakashima AK, Sylvester GC, Surveillance for
geographic and secular trends in congenital syphilis—United States,
1983–1991, MMWR 1993;42(No. SS-6).

ARDI (Alcohol-Related Disease Impact)

Estimate the impact of alcohol consumption

CDC. Deaths and hospitalizations from chronic liver disease and
cirrhosis—United States, 1980–1989. MMWR 1993;41:969–73.
CDC. Alcohol-Related Disease Impact (ARDI). Available at http://apps.
nccd.cdc.gov/ardi/homepage.aspx.

SURVTB

Support state health departments in TB case
surveillance and prevention

CDC. Expanded tuberculosis surveillance and tuberculosis morbidity—
United States, 1993. MMWR 1994;43:361–6.

STELLAR (Systematic Tracking of
Elevated Lead Levels & Remediation)

Support state activities in prevention of
elevated blood lead levels

CDC. State activities for prevention of lead. MMWR 1993;42:165,171–2.

PHLIS (Public Health Laboratory
Surveillance System)

Support reporting from state public health
laboratories

Bean NH, Martin SM, Bradford H, Jr. PHLIS: an electronic system for
reporting public health data from remote sites. Am J Public Health
1992;82:1273–6.

Epi Info

Support data collection and analysis from
field investigations; to support state
surveillance activities

Dean AG, Dean JA, Burton AH, Dicker RC. Epi Info: a general-purpose
microcomputer program for public health information systems. Am J
Prev Med 1991;7:178–82.

FIGURE 3. “Luggable” Osborne computer, circa 1981

the global HIV epidemic, as well as malaria and tuberculosis.
Subsequent work on modeling diseases has been used to monitor and model the impact of influenza outbreaks. During the
1990s, laboratory techniques improved enough so that strains
of viruses could be mapped and links made to the epidemiologic investigation.

The 2000s

Photo: CDC

and behaviors of youth and was the first to gather data from
both high school and middle school students. Findings were
used to design strategies for youth-focused antitobacco campaigns (45). In 1994, economic methods were used to measure
smoking-attributable costs (46).
In 1992, Anderson and May published Infectious Disease
of Humans (47), documenting their work in mathematical
modeling transmission of infectious diseases, which was critically important to understanding the ongoing work in fighting

38

MMWR  /  October 7, 2011  /  Vol. 60

Although today the consequences of unhealthy dietary
choices, sedentary lifestyles, and “supersized” food portions
are familiar, during the late 1990s, their potential for harm
was underestimated. Research published in 1999 documented
the nation’s rapidly increasing obesity rates in all U.S. states,
regions, and demographic groups (48). In 2001, Congress
appropriated $125 million for CDC to develop a national
media campaign to change children’s health behaviors. CDC
responded through VERB, an innovative and expansive campaign based on behavioral science theory and contemporary
principles of marketing, which produced measurable positive
results (49). Once again, CDC epidemiologists were using
statistical analytic methods that had previously been used in
other disciplines. For example, Bayesian methods used by
businesses and marketers to model personal and community
decision making preferences (50) or cluster analysis and
marketing segmentation methods were being used to inform
health intervention and evaluation of health programs (51).

Supplement

FIGURE 4. CDC’s Statistical Achievement Ceremony 1993: Award for
statistical methods to Investigation of 2,3,7,8-tetrachorodibeno-pdioxin half-life heterogeneity in Veterans of Operation Ranch Hand.
Claire V. Broome (presenter), James Pirkle, Samuel Caudill, and
Mitchell Gail (National Institutes of Health)

Photo: CDC

Statistical methods in longitudinal analysis and mixed models
used commonly in social research also contributed to the evaluation of results (52). Likewise, a method developed in 1896
for studies in biological sciences, capture-recapture analysis,
was adapted for evaluating surveillance systems (53,54). This
method facilitated the estimation of total number of cases from
two surveillance sources, each of which might not be complete.
In response to the terrorism events of 2001, statisticians
began to develop methods for use in defense and national
security (55). The rise of spatial statistics and geographic
information systems meant that epidemiologists could better
map prevalence data to suggest gaps in response or impact of
disease or injury (56). Economic data could be mapped for
use in cost-effectiveness studies, and overlaying data types
(prevalence, economic costs, demographics) could be used
for better decision making and for evaluation of programs.
Mapping the cholera outbreak in John Snow’s time seemed
to have come full circle.
Many of the techniques of spatial analysis depend on statistical measures and methods, including univariate statistical
measures and directional analysis (57). Additionally, statistical
methods have been developed to address the specific needs of
spatial datasets. The nature of these extensions differs from
the ways in which multivariate statistics are derived from their
univariate counterparts because of concepts of distance, direction, contiguity, and scale. For example, classical hypothesis
testing and inferential procedures might not be appropriate for
spatial problems because the datasets do not satisfy classical
independence or distributional requirements or because the
sampling frame may be unknown or poorly specified.

The Future of Statistics
In the future, epidemiologists will continue to pursue new
statistical techniques that can increase the impact of their
analyses on public health. For example, the coming decades
might bring innovations in new data collection modalities
(e.g., hand-held data collection methods, cellular phones) and
methods needed to evaluate new public health and medical
interventions, and they will all be packed into a shrinking
global village. A large body of methods (e.g., canonical correlations, factor analyses, exposure assessment, nonparametric
statistics, infectious disease modeling) can be brought to bear
on new public health problems. However, the use of these new
technologies also comes with challenges.
For example, the introduction of parallel sequencing technologies (58) has led to an exponential increase in the amount
of available DNA sequence information for epidemiologic
investigations. Because sequence data are now produced faster
than they can be meaningfully analyzed, new approaches to
the analysis of this information is one of the most important
recent challenges for epidemiologists, bioinformaticians, and
statisticians. Beyond methods to carefully sample and organize
the massive amount of data, challenges include development
of quantitative methods and models to estimate errors for the
various sequencing platforms; algorithms and mathematical
estimates of the reliability of genomes assembled from shortgapped reads; approaches to distinguish sequence-determination errors from biological polymorphism and mutation; and
means to distinguish among multiple genomes within a single
dataset, particularly when the relative sizes of those different
genomes vastly differ.
Challenges especially relevant to the area of biodetection
include development of models for rapid identification of the
differences between the genomes of individuals of a species and
for distinguishing between naturally occurring biological heterogeneity and newly emerged or artificially produced pathogenic
sequences in complex samples. Mathematical models and methods to estimate the significance of genomic variability currently
exist, and the use of these models and methods will increase as
they become easier to use. Nanotechnology, the understanding
and control of matter at dimensions of roughly 1–100 nanometers (10–9 meter), where unique phenomena enable novel
applications, presents specific challenges to statistical methods:
in understanding high variation in experimental results, in
developing sampling plans to model the nanofabrication process
efficiently, and in helping to improve low-quality and unpredictable product reliability. As they have during the past 50 years,
in the coming decades statistical methods will play a major role
in strengthening the evidence base for decisions affecting the
well-being of communities.

MMWR  /  October 7, 2011  /  Vol. 60

39

Supplement

References
1. Anonymous. International Congress of Medicine. Med Officer 1913;10:104.
2. Satcher D. Public Health Service: on the job for 200 years. Public Health
Rep 1998;113:201– 3.
3. Farr W. Report on the mortality from cholera in England, 1848–1849,
London: Her Majesty’s Stationery Office; 1852 [Also published as Farr
W. Registrar General’s report on cholera in England 1849–1850.
London: W. Clowes & Son; 1852].
4. Susser M. Epidemiology in the United States after World War II: the
evolution of technique. Epidemiol Rev 1985;7:147–77.
5. Cohen IB. Florence Nightingale. Sci Am 1984;3:128–37.
6. Thacker SB, Stroup DF, Sencer DJ. Epidemic assistance by the Centers
for Disease Control and Prevention: role of the Epidemic Intelligence
Service. Am J Epidemiol. In press, 2011.
7. Langmuir AD. The surveillance of diseases of national importance. The
challenge of epidemiology: issues and selected readings. Washington,
DC: Pan American Health Organization;13:855–67.
8. Pirkle JL, Brody DJ, Gunter EW, et al. The decline in blood lead levels
in the United States. JAMA 1994;272:284–91.
9. Fox JP, Elveback L, Scott W, et al. Herd immunity: basic concept and
relevance to public health immunization practices. Am J Epidemiol
1971;94:179–89.
10. Sencer DJ, Dull HB, Langmuir AD. Epidemiologic basis for eradication
of measles in 1967. Public Health Rep 1967;82:253–6.
11. Sencer DJ, Millar JD. Reflections on the 1976 swine flu vaccination
program. Emerg Infect Dis 2006;12:29–33.
12. CDC. Typhoid fever—Michigan. MMWR 1982;31:544, 549–50.
13. Wipfli HL, Fujimoto K, Valente TW. Global tobacco control diffusion:
the case of the framework convention on tobacco control. Am J Public
Health 2010;100:1260–6.
14. CDC. A cluster of Kaposi’s sarcoma and Pneumocystis carinii pneumonia
among homosexual male residents of Los Angeles and Orange Counties,
California. MMWR 1982;31:305–7.
15. Jaffe HW, Choi K, Thomas PA, et al. National case–control study of
Kaposi’s sarcoma and Pneumocystis carinii pneumonia in homosexual
men: part 1, epidemiologic results. Ann Intern Med 1983;99:145–51.
16. Jager JC, Heisterkamp SH, Brookmeyer R. AIDS surveillance and
prediction of the HIV and AIDS epidemic: methodological
developments. AIDS 1993;7(Suppl 1):S67–72.
17. Song R, Hall HI, Frey R. Uncertainties associated with incidence
estimates of HIV/AIDS diagnoses adjusted for reporting delay and risk
redistribution. Stat Med 2005;24:453–64.
18. Morgan WM, Curran JW. Acquired immunodeficiency syndrome:
current and future trends. Public Health Rep 1986;101:459–65.
19. Gail MH, Brookmeyer R. Methods for projecting course of acquired
immunodeficiency syndrome epidemic. J Natl Cancer Inst 1988;​
80:900–11.
20. CDC. HIV prevalence estimates and AIDS case projections for the
United States: report based upon a workshop. MMWR 1990;39(No.
RR-16).
21. CDC. 1993 Revised classification system for HIV infection and
expanded surveillance case definition for AIDS among adolescents and
adults. MMWR 1992;41(No. RR-17).
22. Rosenberg PS, Gail MH, Schrager LK, et al. National AIDS incidence
trends and the extent of zidovudine therapy in selected demographic and
transmission groups. J Acquir Immune Defic Syndr 1991;4:392–401
23. Dean AG, Dean JA, Burton AH, Dicker RC. Epi Info: a general-purpose
microcomputer program for public health information systems. Am J
Prev Med 1991;7:178–82.
24. Nieves E, Jones J. Epi Info™: now an open-source application that
continues a long and productive “life” through CDC support and
funding. Pan African Medical Journal 2009;2:6. Available at http://www.
panafrican-med-journal.com/content/feature/2/6/.

40

MMWR  /  October 7, 2011  /  Vol. 60

25. CDC. National Electronic Telecommunications System for Surveillance—
United States, 1990–1991. MMWR 1991;40;502–3.
26. Choi K, Thacker SB. An evaluation of influenza mortality surveillance,
1962–1979. I. Time series forecasts of expected pneumonia and influenza
deaths. Am J Epidemiol 1981;113:215–26.
27. Stroup DF, Thacker SB, Herndon JL. Application of multiple time series
analysis to the estimation of pneumonia and influenza mortality by age,
1962–1983. Stat Med 1988;7:1045–59.
28. Stroup DF, Williamson GD, Herndon JL, Karon JM. Detection of
aberrations in the occurrence of notifiable diseases surveillance data. Stat
Med 1989;8:323–9.
29. CDC. Notice to readers: NCHS National Center for Health Statistics
joins CDC. MMWR 1987:36;390.
30. Stroup DF, Thacker SB. A Bayesian approach to the detection of
aberrations in public health surveillance data. Am J Epidemiol
1993;4:435–43.
31. Nobre FF, Stroup DF. A monitoring system to detect pattern changes
in public health surveillance data. Int J Epidemiol 1994;23:408–18.
32. Simonsen L, Clark M, Stroup DF, et al. A method for timely reporting
of influenza-associated mortality in the United States. Epidemiology
1997;8:390–5.
33. Hutwagner L, Thompson W, Seeman GM, Treadwell T. The bioterrorism
preparedness and response Early Aberration Reporting System (EARS).
J Urban Health 2003;80:i89–96. Available at http://www.syndromic.
org/syndromicconference/2002/Supplementpdf/Hutwagner.pdf.
34. Symposium on statistics in surveillance. Stat Med 1989;8:251–400.
35. CDC. Guidelines for investigating clusters of health events. MMWR
1990;39(No. RR-11):1–16.
36. Smith SJ, ed. Symposium on small area statistics in public health: design,
analysis, graphic and spatial methods. Stat Med 1996;15:1907–86.
37. Falter KH, Betts DR, Rolka DB, Rolka HR, Sieber WK, eds. Symposium
on Statistical Bases for Public Health Decision Making: from exploration
to modelling. Stat Med 1999;18:3159–375.
38. Sieber WK, Green TA, Haugh GS, et al., eds. Symposium on emerging
statistical issues in public health for the 21st century, Stat Med
2001;20:1307–561.
39. Lin LS, Conn JM, Green TA, Johnson CH, Odencrantz JR, Sieber WK
Jr, eds. 8th Biennial CDC and ADSTR Symposium on Statistical
Methods: issues associated with complicated designs and data structures.
Stat Med 2003;22:1359–626.
40. Lipman H, Cadwell BL, Kerkering JC, Lin LS, Sieber WK, eds. Study
design and decision making in public health. Proceedings of the 9th
Biennial U.S. Centers for Disease Control/Agency for Toxic Substances
and Disease Registry (CDC/ATSDR) Symposium on Statistical
Methods. January 27–-29, 2003. Atlanta, Georgia, USA. Stat Med
2005;24:491–669.
41. Davis KE, O’Connor KS, eds. Statistical issues in addressing health
inequalities. Stat Med 2008;27:3925–4144.
42. Utilization of multi-source data: InfoFusion. Available at http://www.
cdc.gov/sag.
43. Sieber WK, Green T, Williamson GD. Statistics and public health at
CDC. MMWR 2006;55(Supl 2):22–4.
44. CDC. Ten great public health achievements—United States, 1900–1999.
MMWR 1999;48:241–3.
45. Nelson DE, Kirkendall RS, Lawton RL, Chrismon JH, et al. Surveillance
for smoking-attributable mortality and years of potential life lost, by
state—United States, 1990. MMWR 1994;43(SS-1):1–8.
46. Nelson DE, Lawton RL, Chrismon JH, et al. Surveillance for smokingattributable mortality and years of potential life lost by State – United
States, 1990. MMWR 1994;43(SS1):1-8.
47. Anderson RM, May RM. Infectious diseases of humans: dynamics and
control. New York, NY: Oxford University Press; 1992.
48. Mokdad AH, Serdula MK, Dietz WH, Bowman BA, Marks JS, Koplan
JS. The spread of the obesity epidemic in the United States, 1991–1998.
JAMA 1999;282:1519–22.

Supplement

49. Huhman ME, Potter LD, Duke JC, Judkins DR, Heitzler CD, Wong
FL. Evaluation of a national physical activity intervention for children:
VERB campaign, 2002–2004. Am J Prev Med 2007;32:38–43.
50. Grover R, Vriens M. The handbook of marketing research: uses, misuses,
and advances. Thousand Oaks, CA: Sage Publications; 2006.
51. Böcker F. Marketing science around the world. Journal of Marketing
1981;45:169–72.
52. Onweugbuzie AJ, Collins KMT. A typology of mixed methods sampling
designs in social science research. Qual Rep 2007;12:281–316.
53. Hall HI, Song R, Gerstle JE 3rd, Lee LM; HIV/AIDS Reporting System
Evaluation Group. Assessing the completeness of reporting of human
immunodeficiency virus diagnoses in 2002-2003: capture–recapture
methods. Am J Epidemiol 2006;64:391–7.

54. Southwood TRE, Henderson P. Ecological mortality. 3rd ed. Oxford:
UK: Blackwell Science; 2000.
55. Elbert Y, Burkom HS. Development and evaluation of a data-adaptive
alerting algotithm for univariate temporal biosurveillance data. Stat Med
2009;28:3226–48.
56. Robinson TP. Spatial statistics and geographical information systems in
epidemiology and public health. Adv Parasitol 2000;47:81–128.
57. De Smith MJ, Goodchild MF, Longley PA. Geospatial analysis—a
comprehensive guide. 3rd ed. London;Winchelsea Press;2009. Available
at http://www.spatialanalysisonline.com/.
58. Pearson TA, Manolio TA. How to interpret a genome-wide association
study. JAMA 2008;299:1335–44.

MMWR  /  October 7, 2011  /  Vol. 60

41

Supplement

Changing Methods of NCHS Surveys: 1960–2010 and Beyond
Monroe G. Sirken, PhD1
Rosemarie Hirsch, MD2
William Mosher, PhD3
Chris Moriarity, PhD4
Nancy Sonnenfeld, PhD5
1Office of the Director, National Center for Health Statistics, CDC, Hyattsville, Maryland
2Division of Health and Nutrition Examination Surveys, National Center for Health Statistics, CDC, Hyattsville, Maryland
3Division of Vital Statistics, National Center for Health Statistics, CDC, Hyattsville, Maryland
4Division of Health Interview Statistics, National Center for Health Statistics, CDC, Hyattsville, Maryland
5Division of Health Care Statistics, National Center for Health Statistics, CDC, Hyattsville, Maryland
Corresponding author: Monroe G. Sirken, PhD, 3114 Gracefield Road, Apt. 405, Silver Spring, MD 20904; Telephone: 301-572-5767; E-mail: [email protected].

Introduction
The year 2011 marks the 50th anniversary of CDC’s publication of MMWR. It also marks the 24th anniversary of the
National Center for Health Statistics (NCHS) joining CDC in
1987. One of NCHS’s greatest contributions to public health
has been in surveys and survey methodology. Today, more than
50 years after NCHS was formed in 1960, NCHS continues
to conduct some of the leading health surveys of the United
States. This report describes some of the many innovations and
changes in NCHS survey methods during the past 50 years and
briefly previews how the methods might change in the future.

A Brief History of NCHS and NCHS
Health Surveys
NCHS is the designated federal statistical agency for compiling, analyzing, and disseminating national health and vital
statistics and for monitoring the health of and health care in
the nation (http://www.cdc.gov/nchs/about/mission.htm).
NCHS was established in 1960 with the merger of two U.S.
Public Health Service agencies, the National Office of Vital
Statistics and the National Health Survey Program (NHS). The
National Office of Vital Statistics, which had been part of the
Public Health Service since transferring from the U.S. Bureau
of the Census in 1946, was responsible for producing national
vital statistics on births, deaths, fetal deaths, marriages, and
divorces. NHS had been created in 1956 after passage of the
Public Health Service Act. Section 306 of the Act authorizes
NCHS to collect national statistics on 1) the extent of illness
and disability; 2) the impact of illness and disability on the
economy; 3) environmental, social, and other health hazards;
4) determinants of health; 5) health resources; 6) use of
health-care resources; 7) health-care costs and financing; and

42

MMWR  /  October 7, 2011  /  Vol. 60

8) family formation, growth, and dissolution. The Act also
directs NCHS to conduct research to develop and improve
methods of health surveys.
Since its founding in 1960, NCHS has conducted 15 distinct major surveys (http://www.cdc.gov/nchs) (Table 1). The
National Health Interview Survey (NHIS) and the National
Health Examination Survey (NHES) were started as part of
NHS in 1957 and 1959, respectively, and continued after
NCHS was established in 1960. The National Health and
Nutrition Examination Survey (NHANES) replaced the
NHES in 1971. The National Survey of Family Growth
(NSFG) was started in 1973, and the first of eight components
of the National Health Care Surveys (NHCS) was started in
1965. The vital records follow-back surveys linked to national
samples of birth and death records have been discontinued
and two random digit-dialed telephone surveys—the National
Immunization Survey and the State and Local Area Integrated
Telephone Survey—have been introduced.

Examples of Major Innovations in
NCHS Survey Methods
Innovations in NCHS survey methods during the past 50
years have been driven largely by advances in information technology and in the statistical, behavioral, and cognitive sciences.
One way to examine these innovations is to categorize them
by the six stages of the survey measurement process to which
they apply: sample design, questionnaire design, data collection, data processing, data dissemination, and data analysis.
Six examples of innovations in NCHS surveys are presented,
one innovation for each measurement stage.

Supplement

TABLE. Principal surveys conducted by the National Center for Health Statistics
Survey*

Periodicity

Household and examination surveys
National Health Interview Survey (NHIS)
National Health Examination Survey (NHES)
National Health and Nutrition Examination Survey (NHANES)
National Survey of Family Growth (NSFG)
Vital record–linked surveys
National Mortality Follow-back Survey (NMFS)
National Natality Follow-back Survey (NNFS)
Health-care surveys
National Hospital Discharge Survey (NHDS)
National Ambulatory Medical Care Survey (NAMCS)
National Nursing Home Survey (NNHS)
National Home and Hospice Care Survey (NHHCS)
National Hospital Ambulatory Medical Care Survey (NHAMCS)
National Survey of Ambulatory Surgery (NSAS)
National Survey of Residential Care Facilities (NSRCF)
National Hospital Care Survey
Random-digit dialed telephone surveys
National Immunization Survey (NIS)†
State and Local Area Integrated Telephone Survey (SLAITS)

Year established

Most recent active year

Annually
Periodically
Annually since 1999
Annually since 2006

1957
1959
1971
1973

2011
1970
2011
2011

Periodically
Periodically

1961
1963

1995
1988

Annually
Annually since 1989
Periodically
Periodically
Annually
Periodically
Periodically
Annually

1965
1973
1973
1992
1992
1994
1989
2011

2010
2011
2004
2007
2011
2006
2010
2011

Annually
Annually

1994
1997

2011
2011

* See Reference 1 for survey descriptions.
† Conducted with the National Center for Immunizations and Respiratory Diseases.

Stage 1. Sample Design:
Network Sampling
Network sampling was introduced by NCHS staff during the
1970s to improve the precision of sample surveys of rare and
elusive populations (2). Network sampling also was applied in
the 1977 NHIS to estimate the national prevalence of diabetes
(3). Subsequently, it was used in the National Ambulatory
Medical Care Survey (NAMCS) to transform estimates of the
numbers of physician office visits into estimates of the number
of persons who visited physicians’ offices (4) and to transform
estimates of the number of practicing physicians into estimates
of the numbers of physician practices (5).

Stage 2. Questionnaire Design: The
Cognitive Research Laboratory
A cognitive research laboratory is a workplace for designing and testing survey questionnaires. Cognitive interviewing
methods are used to detect and eliminate cognitive problems
that respondents have in answering survey questions (6). The
NCHS Questionnaire Design Research Laboratory (QDRL)
was established in 1985. It was the first permanent cognitive
research laboratory in a statistical agency or elsewhere, and it
served as a model for cognitively testing survey questionnaires
that has been adapted by many survey research organizations in
the government and private sectors in this country or elsewhere.

In 2002, the QDRL initiated the development of Q-Bank, a
computerized database of cognitively tested questions. Under
the QDRL’s management, the Q-Bank serves as the federal
interagency repository of cognitively tested survey questions
(http://www.cdc.gov/qbank/home.aspx).

Stage 3. Data Collection: Administrative
Record Linkage
Formally established in the late 1990s, the NCHS
Administrative Record Linkage Program links NCHS data
files with administrative record files (http://www.cdc.gov/
nchs/data_access/data_linkage_activities.htm). However,
some NCHS data files have been linked to some administrative record files since the early and mid-1980s. The Program
expanded the scope of NCHS surveys and increased their
analytic power to examine factors affecting disability, chronic
diseases, health-care use, and illnesses and death (http://www.
cdc.nchs/data_access/data_linkage _activities.htm). The program links NCHS survey files with death records from the
National Death Index; air monitoring data from the U.S.
Environmental Protection Agency; Medicare enrollment and
claims data from the Centers for Medicare and Medicaid
Services; and Retirement, Survivor, and Disability Insurance
and Supplemental Social Security Income benefit data from
the Social Security Administration. A pilot study is under

MMWR  /  October 7, 2011  /  Vol. 60

43

Supplement

way to link NHANES data to state administrative records
for Supplemental Nutrition Assistance Program (formerly
called the Food Stamp Program) and Temporary Assistance
for Needy Families.

Stage 4. Data Processing: Multiple
Imputation for Missing Data
Multiple imputation is a model-based technique for imputing values of missing data in which missing values are independently imputed two or more times (7). Thus, multiple
imputation retains the advantages of single imputation by
decreasing bias due to missing data (if the imputation model
is valid) and allowing data analysts to obtain valid assessments
of variability due to imputation. NHANES III (1988–1994)
became one of the first large-scale multiple imputation applications to impute values of missing data on several variables in a
large public-use data file. NHIS has used multiple imputation
annually since 1997 to impute missing values of personal earnings and family income.

Stage 5. Data Dissemination by Remote
Access: The Research Data Center
In 1988, NCHS established the Research Data Center
(RDC) (http://www.cdc.gov/rdc) to provide off-site researchers
access to NCHS restricted data files while maintaining data
confidentiality. The Research Data Center was modeled after
the Census Bureau’s research data centers. Remote access allows
a researcher to run statistical programs against an analytic data
set created specifically for the approved use. After the output
has been checked for disclosure risk by an NCHS automated
system, it is sent to the researcher. This automated tool for
remote access is unique in the federal statistical system and is
a key element in expanding access to data for the public health
research community.

Stage 6. Data Analysis: Secondary
Analyses of Survey Data
During the 1960s, analyses of NCHS survey data were limited largely to descriptive statistics. However, recent advances
in statistical methods and computer software appropriate for
secondary analyses of data collected in complex sample surveys
has greatly expanded the use of NCHS survey data for research
purposes. For example, NCHS staff pooled 3 NHIS data
years, 1998–2000, to bridge the changes in the classification
of race from single-race reporting to multiple-race reporting
before and after the 2000 population census (8). Advances
in statistical methods and computer software have provided

44

MMWR  /  October 7, 2011  /  Vol. 60

analysts of NCHS public-use data files with capabilities to
address important issues in cancer research (9).

Examples of Survey-Specific
Methodology Changes
The founders of NCHS introduced four complementary
surveys, NHIS, NHANES, NHCS, and NSFG. They viewed
these four surveys as collectively capable of producing the wide
range of national health statistics authorized by NCHS’ legislation. The examples discussed below illustrate how methods of
these surveys have changed during the past 50 years in response
to the evolving needs for health statistics.

The National Health Interview Survey
NHIS, the principal source of national information about
the health of the U.S. civilian population living in households
(10), annually collects information through personal interviews on the reported incidence of acute illness and injuries,
prevalence of chronic conditions and impairments, extent of
disability, use of health services, and in-depth demographic
and socioeconomic data. Collection of these data allows continuing monitoring of the nation’s health (http://www.cdc.
gov/nchs/nhis.htm).

Questionnaire Revisions
The NHIS household questionnaire has undergone revision
approximately every 10 years, reflecting changes in health
measurements, new concepts of health and disease, and evolving factors associated with illness and health. Comparisons of
early with later NHIS questionnaires demonstrate an evolution of perspectives, including 1) shifting from an emphasis
on detailed medical-care use to general access to and use of
health-care services, health behaviors, and perceived health
status; 2) changing from focusing exclusively on the family
unit to including questions about both family and randomly
selected sample persons’ (adults and children) health characteristics, along with requiring self-response from the selected
adult; 3) moving from a paradigm of individual body systems
to a more holistic health approach; and 4) recognizing the need
to address health disparities by collecting information for as
many minority populations as possible within the constraints
of the sample size.
Changes in survey questions have reflected societal changes in
the understanding of health and methodologic refinements in
ways to address issues of importance, such as proxy responses,
recall periods, and definitions of health concepts. In addition to the evolution in concepts and the refinement of key
measurements, the NHIS has adapted to changing methods,

Supplement

moving from pencil and paper administration of the survey
to Computer Assisted Personal Interviewing, which when
adopted in 1997, increased the flexibility of the instrument
and the quality of the resulting data.

Decennial Sample Redesigns
The NHIS household sample has been redesigned after each
Population Census to reflect changes in the size and distribution of the national population. The redesign after the 1980
Census also included an important change in the household
sampling frame. This change enabled NCHS to analyze data in
greater geographic detail; link NHIS files with administrative
records; and use NHIS address listings as sampling frames for
population surveys, including the NCHS’s NSFG, and the
Medical Expenditure Panel Survey conducted by the Agency
for Health Care Research and Quality (11).

The National Health and Nutrition
Examination Survey
NHANES collects data on the health and nutritional
status of the civilian noninstitutionalized U.S. population
through physical examinations and laboratory tests conducted
by trained medical personnel in mobile medical centers.
NHANES enables assessment of diagnosed and undiagnosed
health conditions (12–14). Chronic disease, health and risk
factor status, infectious disease, oral health, nutrition, environmental health, and genetic data are collected (http://www.cdc.
gov/nchs/nhanes.htm).

NHANES Web Tutorial
After NHANES data were made accessible on the NCHS
website in 1998 and personal computer–based statistical software became available, the NHANES user base dramatically
increased and diversified. In 2005, the NHANES Web Tutorial
(NWT) was developed to overcome analytic barriers and
promote broader and more proficient use of NHANES data
(http://www.cdc.gov/nchs/tutorials/). It was the first NCHS
Web tutorial developed and was a collaboration among research
analysts, statisticians and programmers, information technology specialists, instructional designers, and science writers.
NWT is a self-guided, distance-based, multimedia interactive learning tool instructing NHANES users how to 1) efficiently locate pertinent information on the NCHS website; 2)
quickly retrieve NHANES data files and variables to prepare
an analytic dataset; and 3) correctly conduct statistical analyses
with appropriate attention to the nuances of NHANES data,
given its complex sample design, weighting requirements, and
data structure. The tutorial offers analysis tracks in SAS Survey
Procedures, SUDAAN, and Stata. It is a textbook of best

practices for analyzing NHANES data. It is part of the accredited CDC online learning courses and has been used in several
graduate-level university programs. The NWT allows 24/7
data and analysis assistance and has reduced the timeframe for
NHANES analysis proficiency from 3–4 months to 3–4 weeks
for new staff. Because of the success of the initial NWT, five
additional tutorials (environmental health; NHANES I, II, and
III supplemental tutorials; and a full dietary tutorial) have been
developed, and a sixth (physical activity) is being developed.

Community-Level Health Examination Statistics
Although NHANES serves the health examination data
needs on a national level, no comparable program is available for states, local communities, or special populations.
To address these gaps, NHANES provides local areas with
technical expertise to conduct their own health examination
surveys. For example, two projects funded by interested subnational communities have been undertaken. In 2003–2004,
NHANES helped the New York City Department of Health
and Mental Hygiene successfully conduct the first New York
City HANES by using comparable NHANES data collection
and information technology methods for selected conditions,
such as diabetes, high blood pressure, high cholesterol, and
depression (15,16). During 2008–2009, NHANES helped
Oregon prepare for a landmark, statewide study of health and
access to care using similar measures.
These projects stimulated another initiative currently in the
evaluation stage that, if successful, might offer a way to obtain
community-level estimates nested within future NHANES
redesigns for large counties such as Los Angeles County,
California, that are part of NHANES sample every year. A special dataset comprising information collected from NHANES
participants in Los Angeles County during 1999–2004 was
created for this evaluation study (17).

The National Survey of Family Growth
NSFG is based on in-person interviews with national samples
of men and women 15–44 years of age in the household population of the United States. NSFG collects data on marriage
and divorce, sexual activity, infertility, pregnancy outcomes,
contraceptive use, and reproductive health (18,19). These data
help to explain trends and differences in birth and pregnancy
rates, reproductive health, and family formation (http://www.
cdc.gov/nchs/nsfg.htm).

Audio Computer Assisted Interviewing
When NSFG began during the 1970s, it focused on contraceptive use, infertility, and pregnancy among ever-married
women because a relatively small percentage of births were to

MMWR  /  October 7, 2011  /  Vol. 60

45

Supplement

unmarried women (20). However, as the percentage of births
to unmarried women increased (to 18% in 1980 and 39% in
2006 [20]), collecting a wider range of sensitive data became
more important. To do this, in 1993, NCHS began to collect
part of the NSFG interview using Audio Computer Assisted
Survey Interviewing (ACASI). ACASI is a means of collecting
sensitive information in face-to-face interviews in a way that
respects the privacy of respondents and encourages complete
and accurate reporting of sensitive behaviors. In ACASI, the
respondent uses a laptop computer to read the questions while
listening to them through headphones and then enters his or
her responses directly into the computer. The interviewer does
not see or hear the questions or the answers. This method
gives the respondent greater privacy, and it yields more complete reporting of sensitive behaviors than does a paper and
pencil questionnaire (21). In the 1995 NSFG, ACASI was
used primarily to collect data on pregnancy outcomes, but in
2002, the ACASI section of the questionnaire was expanded
to collect data on behaviors that increase the risk for HIV and
other sexually transmitted infections, including male–male sex,
numbers of sex partners, and drug use (22–24).
When NSFG changed from periodic to continuous data collection in 2006, collecting real-time administrative data about
the survey data collection process became increasingly important to manage the survey. Hence, NSFG began to routinely
collect data about the data collection process, called paradata,
including the times of day interviews were conducted, length
of interviews, and number of attempts to complete interviews.
The availability and use of paradata with a 1-day lag between
field actions and receipt of the paradata are helping NSFG
control both the costs and quality of data collection (18,25).
The use of paradata for survey management and cost control
is in its early developmental stages, and much more remains
to be learned about using the paradata to control survey costs,
improve data quality, and maximize response rates (18,25).

The National Health Care Surveys
The National Health Care Surveys, a family of national
surveys of patient encounters with health-care providers in
different settings (Table), collects data directly from health-care
providers on patients’ diagnoses and treatments and on services
provided to patients. These surveys also collect information
about the health providers. The data are used to assess national
patterns in the use, payment, organization, quality, and delivery
of health-care services (http://www.cdc.gov/nchs/nhcs.htm).

46

MMWR  /  October 7, 2011  /  Vol. 60

Survey Integration
As a consequence of introducing new surveys whenever
new settings for delivering health services emerge, NHCS has
conducted eight distinct and independent provider surveys
since 2004. Reducing the number of distinct surveys while
retaining the capability of surveying all providers is simplifying
planning, making the surveys easier to conduct, and potentially
lowering survey costs.
For example, the National Hospital Ambulatory Medical
Care Survey (NHAMCS) was initially fielded in 1992 and
collects information about patients seen in emergency and
outpatient departments of hospitals. The National Survey of
Ambulatory Surgery (NSAS) was initially fielded in 1994–
1996 and collects information about surgical procedures performed in freestanding and hospital-based ambulatory surgery
centers. Initially, NHAMCS and NSAS were independently
designed. After a feasibility study demonstrated a cost-effective
way to integrate the NSAS and NHAMCS sample designs and
data collection methods without loss of data quality, NSAS
was combined with the NHAMCS beginning in 2009. The
vast majority of freestanding surgery centers were selected
from within the NHAMCS primary sampling units, and
hospital-based ambulatory surgery centers were selected from
hospitals already included in NHAMCS. Information about
surgical encounters and patients’ procedures was collected by
using the same data collection form in both freestanding and
ambulatory settings, and data collection forms and methods
were standardized with NHAMCS’s outpatient department
patient record forms.
The increasing use of the electronic medical record system
will be a key issue in designing NHCS in the future as increasingly more health-care providers adopt this technology. NHCS
has been collecting information about the use of electronic
medical records in virtually all of its health-care provider surveys
(http://www.cdc.gov/nchs/data/hestat/emr_ehr/emr_ehr.htm).
At the present time, gathering national data solely from electronic sources would yield highly unrepresentative estimates.
NCHS, however, recognizes that it must prepare for a future
in which data may be gathered mainly from electronic systems.
Many methodologic problems remain to be addressed. These
include identifying the range of data available electronically,
defining the items of interest, defining the properties of these
data (including their levels of completeness and accuracy compared with conventional paper medical records), developing
methods to securely transfer large volumes of confidential data
electronically in a manner acceptable to health-care providers
surveyed, and developing methods to combine data from disparate noninteroperable systems to produce usable data files.

Supplement

Future Directions of NCHS’ Survey
Methods Research Program
Changes in NCHS survey methods will depend on the vigor,
rigor and imagination of its survey methods research program
in maintaining the statistical standards of the Center’s surveys,
while also developing and applying innovative survey methods to meet the ever changing needs for health statistics. The
survey methods research program is an NCHS-wide effort but
is one of the primary missions of the Office of Research and
Methodology (ORM). The principal domains of the NCHS
program are as follows: short-term and long-term research oriented to NCHS’ mission and basic survey research oriented to
the future data needs of the Federal Statistical System. However,
the boundaries between domains are porous, and the findings
of research projects in one domain often lead to new research
projects in other domains.

Mission-Oriented Survey Research
Short-term mission-oriented research responds to the
ongoing programming needs of an NCHS survey, whether
it is NHIS, NHANES, NSFG, or NHCS, and it is usually
conducted by the Survey Division’s staff and often with ORM
support. Examples of ongoing short-term mission-oriented
survey research projects are as follows: NHIS post 2010 Census
sample redesign, NHANES Web tutorials, NSFG’s ACASI,
and NHCS’s integration of the sample designs of NHAMCS,
NSAS, and other health-provider surveys.
Long-term mission-oriented research anticipates the future
programmatic needs of NCHS surveys. Examples of possible
future long-term mission-oriented survey research projects are
as follows: integrating the sample designs of NCHS population
and provider surveys, developing analytic methods to assess
the health effects of social networks in NCHS population
surveys, and assessing the World-Wide Web and the Internet
as potential sampling frames and data-collection modes for
NCHS surveys.

Basic Survey Research
NCHS collaborates with other federal agencies in conducting basic interdisciplinary surveys oriented to the future data
needs of the Federal Statistical System. For example, NCHS
was instrumental in establishing the Funding Opportunity in
Survey and Statistical Research (FOSSR), a grants program that
annually supports investigator-initiated basic survey research
projects related to future needs of federal statistical agencies
(26). Examples of FOSSR-funded research projects are as

follows: cognitive and visual issues in Web survey designs,
model-based replication variance estimators for sample surveys,
and adaptive sample designs in network and spatial settings.
FOSSR is jointly funded by NSF and a consortium of about
a dozen federal statistical agencies, including NCHS, and is
jointly administered by NSF and the Office of Management
and Budget’s Federal Committee on Statistical Methodology.
Acknowledgements
The authors appreciate the comments of Ed Sondik, Jennifer
Madans, Sandra Smith, Iris Shimizu, Van Parsons, Diane Makuc,
Sandra Decker, and Frederic Shaw.
References
1. Kovar MG. Data systems of the National Center for Health Statistics.
Vital Health Stat 1 1989;March:1–21.
2. Sirken MG. Network sampling. In: Armitage P, Colton T, eds.
Encyclopedia of biostatistics. New York, NY: Wiley; 1997: 2977–986.
3. Sirken MG, Graubard BI, McDaniel MJ. National network surveys of
diabetes. Proceedings of the survey methods section (1978). Alexandria,
VA: American Statistical Association; 1978;631–5. Available at http://
www.amstat.org/sections/srms/Proceedings/papers/1978_133.pdf.
4. Burt CW, Hing E. Making patient level estimates from medical encounter
records using a multiplicity estimator. Stat Med 2007:26,1762–74.
5. Hing E, Burt CW. Office-based medical practices: methods and estimates
from the National Ambulatory Medical Care Survey. Adv Data 2007;Mar
12(383):1–15.
6. Sirken MG, Bercini DH. Jobe JB. A PHS laboratory for designing
questionnaires. NCHS Data Line 1990;105:538–9.
7. Rubin DR, Schenker N. Imputation and multiple imputation [Chapter
38]. In: Balakrishman N, ed. Methods and applications of statistics in
the life and health sciences, Hoboken, NJ: Wiley; 2010: 425–40.
8. Ingram DD, Parker JD, Schenker N, et al. United States Census 2000
population with bridged race categories. Vital Health Stat 2 2003
Sep;(135):1–55.
9. Graubard BJ, Korn EL. Analyzing health surveys for cancer related
objectives. J Natl Cancer Inst 1999:91:1005–16.
10. Botman SL, Moore TF, Moriarity CL, Parsons VL. Design and estimation
for the National Health Interview Survey, 1995–2004. Vital Health Stat
2 2000 Jun;(130):1–31.
11. Cohen SB. Sample design of the 1996 medical expenditure panel survey,
medical provider component. Journal of Economics and Social
Measurement 2002:24:25–53.
12. Khrisanopulo MP. Origin, program, and operation of the US National
Health Survey. Vital Health Stat 1 1963 Aug;(27):1–41.
13. Birkner R. Plan and initial program of the health examination survey.
Vital Health Stat 1 1965 Jul;(125):1–43.
14. Miller HW. Plan and operation of the health and nutrition examination
survey. United States—1971–1973. Part A, development, plan, and
operation. Vital Health Stat 1 1973 Feb;(10a):1–46.
15. Thorpe LE, Gwynn RC, Mandel-Ricci J, et al. Study design and
participation rates of the New York City Health and Nutrition
Examination Survey, 2004. Prev Chronic Dis 2006;;3:A94. Epub 2006
Jun 15.
16. Gwynn RC, Garg RK, Kerker BD, Frieden TR, Thorpe LE.
Contributions of a local health examination survey to the surveillance
of chronic and infectious diseases in New York City. Am J Public Health
2009;99:152–9.

MMWR  /  October 7, 2011  /  Vol. 60

47

Supplement

17. Goud VG, Kruszon-Moran D, Porter KS, McQuillan G, Kim-Farley R.
Herpes simplex virus type 1 and type 2 seroprevalence in Los Angeles
County. Finding from the National Health and Nutrition Examination
Survey, 1999–20004. APHA Meetings Online Program, 2010. Available
at http://apha.confex.com/apha/138am/webprogram/Paper226744.
html.
18. Groves RM, Mosher WD, Lepkowski JM, Kirgis NG. Planning and
development of the continuous National Survey of Family Growth. Vital
Health Stat 1 2009 Sep;(48):1–64.
19. Mosher WD, Jones J. Use of contraception in the United States: 1982
–2008. Vital Health Stat 23 2010 Aug;(29):1–44.
20. Martin JA, Hamilton BE, Sutton PD, Ventura SJ, Menacker F, Kirmeyer
S. Births: final data for 2006. Natl Vital Stat Rep 2009;57:1–101.
21. Turner C, Ku L, Rogers S, et al. Adolescent sexual behavior, drug use,
and violence: increased reporting with computer survey technology.
Science 1998;280:867–73.
22. Martinez GM, Chandra A, Abma JC, Jones J, Mosher WD. Fertility,
contraception, and fatherhood: data on men and women from cycle 6
(2002) of the National Survey of Family Growth. Vital Health Stat 23
2006 May;(26):1–142.

48

MMWR  /  October 7, 2011  /  Vol. 60

23. Mosher WD, Chandra A, Jones J. Sexual behavior and selected health
measures: men and women 15–44 years of age, United States, Adv Data
2005 Sep 15;(362):1–55.
24. Anderson JE, Mosher WD, Chandra A. Measuring HIV risk in the US
population aged 15–44: results from cycle 6 of the National Survey of
Family Growth. Adv Data 2006 Oct 23;(377):1–27.
25. Groves RM, Benson G, Mosher WD, et al. Plan and operation of cycle
6 of the National Survey of Family Growth. Vital Health Stat 1 2005;
Aug;(42):1–86.
26. Sirken M. Charting the interdisciplinary history of the Funding
Opportunity in Survey and Statistical Research. In: Seminar on the
Funding Opportunity in Survey and Statistical Research: Statistical
Policy Paper 36. Washington, DC: Office of Management and Budget,
Statistical Policy Office; 2004.

Supplement

Vaccine-Preventable Diseases, Immunizations,
and MMWR — 1961–2011
Alan R. Hinman, MD1
Walter A. Orenstein, MD2
Anne Schuchat, MD3
1Task Force for Global Health, Decatur, Georgia
2Rollins School of Public Health, Emory University, Atlanta, Georgia
3National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia
Corresponding author: Alan R. Hinman, MD, Task Force for Global Health, 325 Swanton Way, Decatur, GA 30030; Telephone: 404-687-5636;
Fax: 800-765-7520; E-mail: [email protected].

Introduction
In the 50 years since MMWR became a responsibility of
CDC, understanding has been enhanced of diseases now prevented by vaccines, many new vaccines have been introduced,
the occurrence of most of these diseases has been dramatically
reduced, and some challenges not previously anticipated have
appeared. This article summarizes some of these changes over
three periods: 1961–1988, 1989–1999, and 2000–2010.
In 1961, children in the United States received vaccines to
prevent five diseases: diphtheria, tetanus, pertussis, poliomyelitis, and smallpox. Now children receive vaccines to prevent
16 conditions: diphtheria; Haemophilus influenza type b,
hepatitis A, hepatitis B, and human papillomavirus infections;
influenza, measles, meningococcal disease, mumps, pertussis,
pneumococcal disease, poliomyelitis, rotavirus infections,
rubella, tetanus, and varicella (Table 1). Immunization coverage
rates among preschool-aged children are high (Figure 1), and
most diseases have declined to historically low levels (Table 2).

1961–1988: Establishment of a
Nationwide Immunization Program
Vaccination Assistance Act
Before 1962, no formal nationwide immunization program
existed. Vaccines were administered in private practices and
local health departments and paid for out of pocket or provided
by using state or local government funds with some support
from federal Maternal and Child Health Block Grant funds.
In 1962, the Vaccination Assistance Act (Section 317 of the
Public Health Service Act) was passed to “achieve as quickly
as possible the protection of the population, especially of all
preschool children…through intensive immunization activity
over a limited period of time…” The initial intention was to
allow CDC to support mass, intensive vaccination campaigns.
However, the Vaccination Assistance Act also established a
mechanism to provide ongoing financial support to state or

TABLE 1. Year of U.S. licensure of selected childhood vaccines
Vaccine

Year of first US licensure

Tetanus toxoid
Trivalent inactivated influenza
Tetanus and diphtheria toxoids
Inactivated polio
Oral polio
Diphtheria–tetanus–pertussis
Diphtheria–tetanus–acellular pertussis
Measles–mumps–rubella
Hepatitis B
Haemophilus influenzae type b conjugate
Hepatitis A
Varicella
Pneumococcal conjugate
Live attenuated influenza
Tetanus–diphtheria–acellular pertussis
Meningococcal conjugate
Rotavirus
Human papillomavirus

1943
1945
1953 for children aged >7 yrs;
1970 for children aged <7 yrs
1955
1963
1970
1991
1963 (measles); 1967 (mumps);
1969 (rubella); 1971 (measles–
mumps–rubella combined)
1981 (plasma derived); 1986
(recombinant)
1987 for children aged ≥18 mos;
1990 for infants
1995
1995
2000 (7-valent); 2010 (13-valent)
2003
2005
2005
2006
2006

local health departments and direct support “in lieu of cash.”
The direct support included provision of vaccines and of CDC
Public Health Advisors to assist in managing the programs.
Section 317 has been reauthorized repeatedly since 1962 and
remains one of the most important means of supporting health
department immunization activities with federal funds (1).
At the initiation of the 317 funding program in 1963,
the only vaccines routinely recommended for children were
diphtheria and tetanus toxoids and pertussis vaccine (DTP),
polio, and smallpox. Measles vaccine was licensed in 1963,
and in 1966, a goal was set to eradicate measles from the
United States (2). Measles incidence declined dramatically
after large vaccination campaigns, but transmission was not
interrupted. The licensure of rubella vaccine in 1969 led to
mass campaigns to immunize children to avert an anticipated
repeat of the tragic epidemic of 1964–65, which resulted in
the births of approximately 20,000 infants with congenital

MMWR  /  October 7, 2011  /  Vol. 60

49

Supplement

FIGURE. Increasing vaccine-specific coverage rates among preschool-aged children — United States, 1967–2009
100

80

DTP/DTaP (3+)*
PCV 7
(4+)

Percentage

Hep B (3+)
60

MMR (1+)
Polio (3+)
40

Rotavirus
(3+)

Hib (3+)

Varicella
(1+)

20

0
1967

1970

1973

1976

1979

1982

1985

1988

1991

1994

1997

2000

2003

2006

2009

Year
Abbreviations: MMR = measles-mumps-rubella; DTP/DTaP = diphtheria and tetanus and acellular pertussis; Hib = Haemophilus influenza type b; Heb B = heptatitis B;
PCV7 = 7-valent pneumococcal conjugate vaccine; USIS = United States Immunization Survey; NHIS = National Health Interview Survey; NIS = National Immunization
Survey; NCHS = National Center for Health Statistics; NIP = National Immunization Program; NCIRD = National Center for Immunization and Respiratory Diseases.
* DTP(3+) is not a Healthy People 2010 objective. DTaP(4) is used to assess Healthy People 2010 objectives.
Note: Children in the USIS and NHIS were 24–35 months of age. Children in the NIS were 19–35 months of age.
Source: USIS (1967–1985), NHIS (1991–1993) CDC, NCHS, and NIS (1994–2009), CDC, NIP and NCHS; No data during 1986–1990 due to cancellation of USIS because
of budget reductions.

rubella syndrome. The rubella campaigns diverted attention
and funding from measles, resulting in a resurgence of measles.
Federal funding for Section 317 declined during the early to
mid-1970s. Immunization coverage fell, and disease increased.
In April 1977, a Childhood Immunization Initiative was
announced with two goals: attainment of immunization levels
of 90% in the nation’s children by October 1979 and establishment of a permanent system to provide comprehensive
immunization services to the 3 million children born each
year in the United States. Increased funding was provided
through Section 317, and a major effort was made to review
vaccination records of school children and vaccinate those in
need. State and local public health personnel reviewed >28
million records during a 2-year period. In addition, state and
local authorities enacted and enforced school immunization
requirements. By 1980, all 50 states had such laws, and since
1981, immunization levels of students entering schools have
been ≥95%. Thus, the first target of the initiative was met.
Achieving the second target would take considerably longer.
A major weakness of Section 317 in its early years was the
assumption that state and local health departments could

50

MMWR  /  October 7, 2011  /  Vol. 60

provide the infrastructure necessary to actually administer vaccines. Consequently, Section 317 funds were not authorized
for paying salaries of persons who administered the vaccines.
The result was that local health departments became increasingly unable to provide the services necessary to ensure that
preschool-aged children received vaccines on time, and private
sector clinicians were not filling this need, particularly in lowincome communities. Additionally, no system was in place to
monitor immunization coverage in preschool-aged children, so
obtaining an accurate picture of population susceptibility was
not possible. Inevitably, this situation led to an accumulation
of susceptible children and a consequent resurgence of measles
by the end of the decade.

Advisory Committee on Immunization
Practices
Until 1964, recommendations about the use of vaccines in
the United States were made by the American Academy of
Pediatrics, the American Public Health Association, and other
professional groups. The federal government’s involvement

Supplement

TABLE 2. Comparison of annual morbidity from vaccine-preventable
diseases during the 20th century and 2009
Disease
Diphtheria
Hepatitis A
Hepatitis B, acute
Haemophilus influenzae type b
in children aged <5 yrs.
Measles
Mumps
Pertussis
Pneumococcus, invasive
All ages
<5 yrs
Poliomyelitis, paralytic
Rotavirus, hospitalizations
Rubella
Congenital rubella syndrome
Smallpox
Tetanus
Varicella

20th Century*
21,053
117,333
66,232
20,000

2010†
0
8,493§
9,419§
240¶

% Reduction
100
93
86
99

530,217
162,344
200,752

63
2,612
27,538

>99
98
86

63,607
16,069
16,316
62,500**
47,745
152
29,005
580
4,085,120

44,000††
4,700††
0
28,125§
5
0
0
26
408,572§

30
72
100
55
>99
100
100
96
90

* Estimated annual average number of cases in the prevaccine era for each
disease. Source: JAMA 2007;298:2155–63.
† Source: MMWR 2011;60(32):1088–1101.
§ 2009 estimate.
¶ 23 type b and 223 unknown serotype (among children <5 years of age).
** Source: MMWR 2009;58(No. RR-2).
†† Source: http://www.cdc.gov/abcs/reports-findings/survreports/spneu09.html.

occurred through convening ad hoc expert advisory groups to
address individual issues, such as the results of the field trial
of Jonas Salk’s inactivated polio vaccine (IPV) and the subsequent incident of paralysis related to incompletely inactivated
vaccine manufactured by Cutter Laboratories. Federal ad hoc
groups also provided advice about the influenza pandemic
of 1957, Albert Sabin’s attenuated oral polio vaccine (OPV),
and soon-to-be licensed measles vaccines. The frequency and
complexity of issues led CDC to propose an ongoing Advisory
Committee on Immunization Practices (ACIP), which was formally established in 1964. ACIP served as a technical advisory
committee to the Public Health Service. It comprised eight
members, including the CDC Director, who served as Chair.
Today, ACIP continues to provide formal advice to CDC and
the U.S. Department of Health and Human Services; after
approval, ACIP recommendations are published in MMWR
and are available on the Internet (3,4).
Initially ACIP directed its recommendations to public health
agencies; recommendations for private practitioners were
developed by the American Academy of Pediatrics and other
professional societies. To improve consistency in recommendations, liaison members from the societies have been appointed,
and since 1994, all childhood vaccination recommendations
have been standardized and endorsed by the Public Health
Service and by professional societies. ACIP recommendations
have major impact on immunization policies and practice in
the United States and in other countries.

Monitoring of Adverse Events
The importance of monitoring and investigating adverse
events following immunization (AEFI) is exemplified by the
Cutter incident of 1955 and investigations into paralysis associated with OPV during the early 1960s. Investigations into
adverse events associated with routine smallpox vaccination
contributed substantially to the U.S. decision to discontinue
routine smallpox vaccination in 1972, years before smallpox
was eradicated globally. Reports of Guillian-Barré syndrome
after receipt of swine influenza vaccine in 1976 led to nationwide investigations and contributed greatly to the development
of CDC’s Monitoring System for Adverse Events Following
Immunization. This system was the forerunner of the current
Vaccine Adverse Event Reporting System (VAERS), which was
established legislatively by the National Childhood Vaccine
Injury Act of 1986. VAERS is a passive surveillance system
receiving reports of AEFI from providers, parents, and others. Approximately 30,000 such reports are received each year.
VAERS reports describe a temporal association and cannot
prove causal relationships. CDC and others have developed
additional systems to permit investigation of causality. Premier
among these is the Vaccine Safety Datalink, a network of
eight large medical-care organizations that tracks all medical
encounters (including receipt of vaccine) in approximately 9
million persons (approximately 3% of the U.S. population) (5).

Influenza
Surveillance of influenza disease activity and virologic characteristics are published regularly in MMWR, as are ACIP’s
recommendations for influenza vaccine use. The emergence
of influenza A (H3N2) virus caused the influenza pandemic
of 1968–69, and response to an A (H1N1) virus in 1976 led
to the national “swine flu” vaccination program that year.

Vaccine Liability and the National
Childhood Vaccine Injury Act
Manufacturers’ concerns about their liability exposure to
lawsuits related to AEFI (particularly paralysis after receipt
of OPV) led them to transfer responsibility to the U.S. government for informing recipients of vaccine risks, as well as
benefits, for vaccines administered in the public sector. The
result was development of Vaccine Information Statements
describing the risks and benefits and a federal requirement
that each recipient (or parent) receive this notification for
each dose of each vaccine. Lawsuits against manufacturers of
DTP vaccine increased dramatically in the early 1980s after
allegations that DTP caused permanent brain damage and
sudden infant death syndrome. Some DTP manufacturers left
MMWR  /  October 7, 2011  /  Vol. 60

51

Supplement

the market, and prices of DTP from the remaining producers
rose dramatically. In 1986, the National Childhood Vaccine
Injury Act was enacted, which put in place a no-fault compensation program for persons who had been injured after receipt
of a vaccine that was universally recommended for children
(no matter the age of the recipient). This Act also formally
established VAERS, the National Vaccine Program Office,
the National Vaccine Advisory Committee, and the Advisory
Commission on Childhood Vaccines. Lawsuits against manufacturers declined dramatically.

Introduction of New Vaccines and
Reduction of Disease during the
1960s–1980s
The incidence of polio declined dramatically after introduction of IPV in 1955 and further after introduction of OPV
in 1961. The last case of paralysis from indigenously acquired
polio infection in the United States occurred in 1979; the
entire region of the Americas was certified free of polio in
1994. Introduction of measles vaccine in 1963 led to calls
for eradication in 1966 and subsequently for elimination by
October 1, 1982. Neither target was met, but measles incidence
declined greatly. Introduction of rubella vaccine in 1969 led to
a dramatic decline in reported rubella and congenital rubella
syndrome and interrupted the cycle of recurrent epidemics at
6–9-year intervals that preceded vaccine availability.
The Certification Panel declared eradication of smallpox on
December 9, 1979, and the World Health Assembly adopted
the resolution declaring eradication on May 8, 1980. The last
naturally occurring case occurred in 1977. Smallpox remains
the only disease of humans to have been eradicated from the
world thus far, but polio and dracunculiasis are nearing their
eradication goals.

1989–1999: Measles Resurgence
and Response
In 1989, after almost a decade (1980–1988) during which
an average of approximately 3,000 measles cases were reported
annually, a major resurgence began that fundamentally changed
the immunization program in the United States (6). During
1989–1991, approximately 55,000 measles cases were reported,
resulting in approximately 11,000 hospitalizations and 123
deaths. Early in the outbreak, multiple outbreaks were identified among college and high school students for whom coverage with a single dose of measles vaccine was high. During the

52

MMWR  /  October 7, 2011  /  Vol. 60

1980s, recognizing that measles could be transmitted among
the 2%–5% of persons who did not make a primary immune
response to a first dose of measles vaccine, ACIP-recommended
mass revaccination campaigns as part of measles outbreak control efforts. These emergency responses were costly and logistically difficult to implement and required major diversions of
resources toward outbreak control from other immunization
and public health priorities. Efforts to control the multiple
outbreaks among college students brought this issue to a head,
and in 1989, ACIP recommended a routine second dose of
measles–mumps–rubella vaccine (MMR) be administered to
all children, usually at entry to school (4–6 years of age).
The major problem with measles during the resurgence
was disease, not in college students, but in unimmunized
preschool-aged children, often living in inner cities, and disproportionately members of racial and ethnic minority groups (7).
Initially, the cause of the lack of vaccination was believed to be
lack of access to measles vaccine. A series of studies showed that
most children had access to a provider and that many had seen
a health-care provider during a time when they were eligible
for measles vaccination but that vaccination was not offered.
Reasons for health-care providers to fail to take advantage of
opportunities to vaccinate children included adherence to
presumed contraindications that were not valid, reluctance to
offer several vaccines simultaneously when multiple vaccines
were indicated, and referral of children from private providers when parents could not pay for vaccines to public clinics
where vaccines were free. The measles resurgence spurred
efforts to develop comprehensive state- and community-based
Immunization Action Plans that laid out the steps needed to
achieve at least 90% immunization coverage of preschool-aged
children for all recommended vaccines at the recommended
ages during the first 2 years of life.
In 1991, the National Vaccine Advisory Committee issued
recommendations laying out the blueprint for the future
immunization program (6,7). Some of those recommendations
included using federal Section 317 grant funds for actual delivery of vaccines and not simply for vaccine purchase and program administration; developing “Standards for Immunization
Practice,” guidelines to optimize vaccine delivery to reduce
vaccine-preventable diseases; building coalitions of public and
professional partners for immunization; ensuring children in
other public programs (such as Women, Infants, and Children
programs) were vaccinated; and enhancing assessment of
immunization coverage of preschool-aged children to determine population susceptibility gaps so actions could be taken
to prevent outbreaks of vaccine-preventable diseases.

Supplement

Childhood Immunization Initiative
and Development of the Vaccines for
Children Program
In 1993, a second Childhood Immunization Initiative was
undertaken with the goal of achieving, by 1996, 90% immunization coverage among preschool-aged children for vaccines
recommended during the first 2 years of life. A critical part of
the Childhood Immunization Initiative was to eliminate financial
barriers to vaccination and ensure children could be vaccinated
at their site of usual care (“medical home”), typically a private
provider’s office. The Vaccines for Children (VFC) program,
established through the Omnibus Reconciliation Act of 1993,
initiated an entitlement program for vaccines recommended
by ACIP for children who were Medicaid eligible, completely
uninsured, or American Indian/Alaska Native. In addition,
VFC covered children whose insurance did not cover vaccinations (“underinsured”)—but only if they received vaccines
at Federally Qualified Health Centers (8). Importantly, VFC
authorized ACIP to play the decisive role in which vaccines
would be covered, automatically financing vaccines ACIP voted
into the program. The VFC grew to cover approximately 45%
of U.S. children, including about 70% of African-American and
Hispanic children.
Another critical component of Childhood Immunization
Initiative was the establishment of the National Immunization
Survey (NIS). Starting in 1994, the NIS, through randomdigit dialing surveys, obtained statistically valid immunization
coverage rates for all 50 states and several urban areas, allowing
tracking of progress toward meeting national goals and identification of problem areas for special interventions. The NIS
documented that in 1996, ≥90% coverage was achieved for the
following vaccines routinely recommended for preschool-aged
children: DTP (three or more doses), polio (three or more
doses), MMR (one dose), and Haemophilus influenza type b
(Hib) (three or more doses). The Childhood Immunization
Initiative goal of 70% coverage with three or more doses of
hepatitis B vaccine also was met. Furthermore, racial and ethnic
disparities in immunization rates, once as high as 20 percentage
points for measles, had substantially narrowed (9).

Introduction of New Vaccines and
Reduction of Disease, 1989–1999
During 1987–1999, several new vaccines were added to the
childhood immunization schedule (Table 1), including Hib
conjugate vaccines and hepatitis B vaccines for infants, IPV
(replacing OPV), replacement of whole-cell pertussis vaccines

with acellular vaccines, and varicella vaccine for all children
during the second year of life.
Before the availability of Hib vaccine, an estimated 20,000
children each year developed invasive Hib disease, including
12,000 who developed meningitis. Extensive use of Hib vaccine
markedly reduced these numbers and was associated with not
only direct protection but with herd immunity as well (10).
Children who acquire chronic hepatitis B virus inf ection in
early life have a 15%–25% lifetime risk for early death from
liver failure and liver cancer. Before hepatitis B vaccine was
available, >25,000 cases of acute hepatitis B virus infection
were reported to CDC annually, and an estimated 30%–40%
of chronic infections resulted from perinatal or early childhood
infections. Initial efforts to reduce the lifetime burden of hepatitis B infection acquired in early life focused on screening highrisk (1984) and then all pregnant women (1988) for chronic
hepatitis B virus infection and timely postexposure vaccination
and hepatitis B immunoglobulin for their infants. Since 1991,
hepatitis B vaccination has been recommended for all infants
to reduce their lifetime risk for hepatitis B virus infection and
to provide a safety net for infants who might otherwise not
receive timely postexposure prophylaxis. In a strategy to eventually eliminate transmission of hepatitis B virus infection in the
United States, vaccination has been recommended for adults at
high risk for hepatitis B infection (since 1982) and all unvaccinated children and adolescents 0–18 years (since 1999). By
2000, at least 90% of infants were being vaccinated annually.
In 2007, declines in reported cases of acute hepatitis B since
1998 were 92% for persons aged <20 years, 59% for persons
20-49 years, and 46% for persons ≥50 years (11).
During the early 1980s, allegations surfaced that whole-cell
pertussis vaccines, the standard vaccines in use in the United
States at the time, caused serious adverse reactions, including
permanent brain damage. Although studies did not confirm
these allegations, extensive efforts were made to develop acellular pertussis vaccines. These acellular vaccines were associated
with substantially lower rates of fever and local reactions than
were whole-cell vaccines. In 1991, acellular vaccines became
available for the fourth and fifth doses of the five-dose DTP
series; in 1997, acellular vaccines were recommended for the
first three doses as well.
In 1995, varicella vaccine was licensed. Varicella accounted
for an estimated 10,000 hospitalizations and 100 deaths each
year in the United States. In 1996, ACIP recommended that all
children be vaccinated against varicella with a single dose of vaccine. A universal two-dose regimen was recommended in 2006.
The last outbreak of wild-virus polio occurred in the United
States in 1979. However, as a result of the exclusive use of
OPV, approximately seven to eight cases of polio caused by the
vaccine were reported each year (vaccine-associated paralytic
MMWR  /  October 7, 2011  /  Vol. 60

53

Supplement

polio [VAPP]). These cases occurred in OPV recipients and in
contacts of recipients. Persons with immune defects (primarily
B cell) were at highest risk. With progress in the worldwide
effort to eradicate polio, ACIP recommendations were updated
in January 1997 to promote a sequential schedule of two doses
of IPV followed by two doses of OPV to reduce the occurrence of VAPP. Because VAPP continued to occur in contacts
of vaccine recipients, in June 1999, ACIP recommended that
an all-IPV schedule be implemented no later than 2000. The
all-IPV schedule has resulted in the near elimination of VAPP
in the United States (12).
Diarrhea and dehydration caused by rotavirus accounted
for an estimated >400,000 health-care provider visits,
55,000–70,000 hospitalizations, and 20–60 deaths annually in
the United States. In 1998, RotaShield (Wyeth Laboratories,
Marietta, Pennsylvania), a rotavirus vaccine derived from a
strain isolated from rhesus monkeys and reassorted with three
other (human) strains, was licensed. The vaccine was recommended universally for young infants. However, postlicensure
surveillance documented a clustering of intussusception cases,
primarily within the 3–14 days after the first dose. ACIP recommended routine vaccination stop pending further studies.
A subsequent large case–control study confirmed an attributable risk for intussuception of approximately one in 10,000
first doses associated with the rhesus reassortant vaccine, and
RotaShield vaccine was withdrawn (13). No documented cases
of intussuception were reported following vaccine administered
after July 16, the date of the MMWR publication, suggesting
that the notice in MMWR led to marked reductions in rotavirus vaccine use.

Thimerosal
Thimerosal, an ethyl mercury–containing preservative, was
added to several inactivated vaccines in multidose vials to avoid
bacterial overgrowth of those vials should bacteria be introduced on repeated entry to withdraw additional doses. Before
1990, the only thimerosal-containing vaccine recommended
for infants was DTP. However, recommendations for Hib and
hepatitis B vaccines increased the amount of thimerosal to
which infants were exposed. Overall, during the first 6 months
of life, the amount of ethyl mercury in vaccines recommended
for infants could exceed the levels recommended for safety
by the U.S. Environmental Protection Agency for methyl
mercury (a more toxic compound) but not the safety levels
recommended by the Agency for Toxic Substances and Disease
Registry or the Food and Drug Administration. At the time this
level was recognized in 1999, no data existed to suggest any
harm from the amount of ethyl mercury in vaccines. However,

54

MMWR  /  October 7, 2011  /  Vol. 60

as a precaution, CDC recommended in 1999 that manufacturers work to decrease the amount of thimerosal in their vaccine
products as soon as feasible (14). Use of thimerosal-containing
vaccines was still recommended, until an adequate supply of
vaccines not requiring a thimerosal preservative was available,
to avoid the known consequences of a potential resurgence of
serious vaccine-preventable diseases. Thimerosal as a preservative was generally removed by adopting single-dose packaging.
Subsequent studies, including extensive research on an alleged
link of thimerosal in vaccines with autism, have not supported
a causal role of thimerosal in a variety of neurodevelopmental
disorders, including autism (15).

2000–2010: New Century, New
Vaccines, New Challenges
During the first decade of the 21st century, several new
vaccines were introduced in the United States. Pneumococcal
conjugate (PCV7 [2000]; PCV13 [2010]), meningococcal conjugate (2005), tetanus–diphtheria–acellular pertussis (Tdap,
adult formulation, 2005), rotavirus (2006), human papillomavirus (2006), and zoster (2006) vaccines were recommended
for routine use during this period (Table 1). Recommendations
for influenza vaccines were incrementally expanded; this
trend culminated in a universal influenza vaccination policy
adopted in 2010. The vaccines licensed during this decade
were substantially more expensive than were earlier vaccines,
and consideration of the cost-effectiveness of each new vaccine
became a major component of ACIP’s deliberations related
to routine use. During this decade, disease was substantially
reduced within the vaccination-targeted age groups, as well
as within unvaccinated populations. Major herd immunity
benefits were associated with use of pneumococcal conjugate
(16) and hepatitis A vaccines, in particular. Immunization
coverage for the infant vaccination series (DTap–IPV–MMR–
Hib–hepatitis B–varicella) neared the Healthy People 2010
target of 80% (17). For each birth cohort vaccinated with this
series, an estimated 20 million fewer illnesses occur, 42,000
premature deaths are prevented, and $13.6 billion in direct
medical costs are saved. Direct and indirect savings to society
are estimated to total $69 billion (18).

The Changing Epidemiology of
Vaccine-Preventable Disease
Although most vaccine-preventable diseases were at record
low levels during this decade, several communities or institutions experienced resurgences of some vaccine-preventable

Supplement

diseases, especially pertussis, mumps, and varicella. Certain
factors associated with resurgent disease prompted new
immunization policies (19). Waning immunity associated with
pertussis vaccines administered during childhood prompted
development of pertussis vaccine formulations that were suitable for older age groups and led to Tdap recommendations
for routine adolescent and adult immunization. A single dose
of varicella vaccine proved to be 85% effective, not sufficient
to prevent varicella outbreaks; this finding prompted the 2006
recommendation for a routine two-dose series. Outbreaks of
mumps concentrated in the midwestern United States during
2006 and the northeastern United States during 2009–2010
occurred in colleges or religious schools, despite high twodose coverage. Indigenous measles and rubella were declared
eliminated in 2000 and 2004, respectively. After elimination of
endemic transmission of measles in the United States in 2000,
importation of measles virus continued in low numbers annually, with limited spread. However, in 2008 more than twice
the average number of annual cases occurred, associated with
clustering of unimmunized children whose parents had intentionally avoided vaccinating their children (20). In some states,
the rate of personal belief exemptions from school requirements
for measles vaccine increased. Recognition of parental concerns
about the number and timing of early childhood vaccines
has renewed efforts to address communication needs of both
providers and parents (21) and strengthen understanding of
changing attitudes associated with immunization decisions.

Public Health Emergencies
and a Pandemic
Public health emergencies during the 2000s led to some
extraordinary mass vaccination efforts. The 2001 bioterrorist
anthrax attack resulted in postexposure antimicrobial prophylaxis followed by voluntary vaccination of approximately
1,700 persons who had occupational exposure to envelopes
contaminated with Bacillus anthracis spores. Preparedness for
additional bioterrorist threats led the federal government to
implement a smallpox vaccination program for civilian public
health responders that reached nearly 40,000 workers) (22).
These emergency programs were dwarfed in magnitude by the
immunization program mounted in response to the first influenza pandemic in 41 years. The vaccination program against
2009 pandemic influenza A (H1N1) resulted in vaccination
of an estimated 80 million U.S. residents with >90 million
doses of monovalent (H1N1) vaccine (23). The pandemic
influenza immunization program in the United States was
accompanied by unprecedented levels of public and media
communication and enhanced vaccine safety monitoring to

optimize public acceptance. Results available thus far suggest
that the monovalent pandemic (H1N1) vaccine had similar
safety performance to seasonal trivalent influenza vaccines
and much lower risk for Guillain Barré syndrome than that
seen with the 1976 swine influenza vaccination program (24).

Immunization Information Systems
Immunization information systems (IIS, immunization
registries) are confidential, population-based, computerized
databases that record all vaccine doses administered by participating providers to persons residing within a given geopolitical
area. IIS have been under development since the early 1990s
and now are in place in 48 of 50 states. As of December 31,
2008, 75% of children aged <6 years were enrolled in an IIS,
with at least two vaccinations recorded. An increasing proportion of IIS now cover the lifespan of the individual. The Task
Force on Community Preventive Services recently reviewed the
evidence base for the effectiveness of IIS and recommended IIS
on the basis of strong evidence of effectiveness in increasing vaccination rates. Public health efforts are under way to improve
interoperability between IIS and electronic medical records.

Global Efforts
Global efforts to reduce vaccine-preventable disease accelerated during this period, aided by catalytic investments of the
Bill & Melinda Gates Foundation (www.gatesfoundation.org),
as well as the formation in 2000 of the Global Alliance for
Vaccines and Immunization and the associated Vaccine Fund
(now GAVI Alliance) (www.gavialliance.org). Use of hepatitis B and Hib vaccines in resource-poor countries increased
markedly. The World Health Organization (WHO) now
recommends all infants receive hepatitis B vaccine as soon as
possible after birth and all regions and associated countries
develop goals for hepatitis B control. The Measles Initiative, a
partnership of the American Red Cross, CDC, WHO, United
Nations Children’s Fund, and the United Nations Foundation,
spearheaded efforts to reduce global deaths from measles by
90% from 2000 to 2010. Tremendous progress has been
achieved, especially in the African region, through sustaining
strong immunization services and second-dose opportunities
through supplemental immunization activities (SIAs) or as a
routine second dose. Maintenance of these activities will be
vital to maintaining progress (25). Outbreaks of measles were
reported in 30 countries in Africa during 2010 as a result of
delays in carrying out SIAs.

MMWR  /  October 7, 2011  /  Vol. 60

55

Supplement

Vaccine-Preventable Diseases,
Immunizations, and MMWR

During the second decade of the Global Polio Eradication
Initiative (26), the number of countries in which endemic transmission had never been interrupted fell to four: Afghanistan,
India, Nigeria, and Pakistan. However the program suffered a
major setback in 2003 when Nigeria temporarily stopped polio
vaccination. Cases increased substantially in Nigeria, and the
virus was exported to 20 previously polio-free countries during 2003–2006, requiring major response efforts. By summer
2010, both Nigeria and India had documented substantial
reductions in wild poliovirus infections compared with earlier
years. However, a large outbreak of wild poliovirus type 1 in
Tajikistan detected during spring 2010 emphasized the fragility
of elimination efforts that have been achieved in some regions
and the importance of supporting strong routine immunization efforts and sustaining heightened surveillance for poliovirus and acute flaccid paralysis. Attainment of Millennium
Development Goal 4—to reduce child mortality by two thirds
by 2015 from 1990—will depend in part on strengthening
immunization systems and introducing pneumococcal and
rotavirus vaccines to areas of high mortality in sub-Saharan
Africa and Asia.

MMWR has played a major role in chronicling key events
related to vaccine-preventable diseases and immunization, carrying articles about outbreaks of vaccine-preventable diseases
(even before vaccines were available for many of them), the
effect of vaccines, vaccine coverage, AEFI, and the recommendations of ACIP. A review of the tables of contents of articles
published in the MMWR weekly during 1965–2009 (tables
of contents were not published before 1965) indicates >2,500
articles published—an average of approximately one article per
week over the entire period (Table 3). Articles on influenza were
most numerous (684), followed by measles (451), polio (249),
“other” (238), and ACIP recommendations (237). Many of the
episodes first reported in MMWR were subsequently published
in peer-reviewed journals.

The Future
During the past 50 years, immunization has led to elimination or near elimination of several vaccine-preventable diseases
in the United States and has substantially reduced deaths, disabilities, and illness. Maintaining success depends on sustaining

TABLE 3. MMWR articles in which vaccines and vaccine-preventable diseases are the sole or primary topic, 1965–2009*
Topic
Articles from ACIP
Diphtheria
Hepatitis A
Hepatitis B
Hepatitis, other§
Hib
HPV
Influenza
Measles
Meningococcal
disease
Mumps
Pertussis
Pneumococcal
disease
Poliomyelitis
Rotavirus
Rubella
Smallpox
Tetanus
Varicella
Zoster
Other¶
Total
Grand total

1965–1969 1970–1974 1975–1979 1980–1984 1985–1989 1990–1994 1995–1999 2000–2004 2005–2009
23
19
0
1
40/1†
0
0
73/22†
137
33/1†
3
2
0

16
20/2†
12/1†
10
18
4
0
63/21†
48/1†
10/2†
4
0
0

27/3†
0
4
8/36†
5/1†
1
0
1
377/64†
441

10/7†
0
17/2†
3/36†
1
5
8
3
252/72†
324

34
5/1†
4
2
10
1/1†
0
65/40†
48/3†
8/1†

27
1
4
6
2
0
0
86/10†
79/4†
1

2
4/1†
1/3†

4/1†
5/1†
2

12/11†
0/1†
18
5/20†
1
0/1†
7
7
234/83†
317

5/5†
0
16
7/4†
0
2/1†
2
4/1†
253/27†
280

29
0
1
8
4/1†
3
0
67/9†
36/3†
1/1†
4
2
3
2/6†
0
11
1/1†
3
1
0
10
186/21†
207

25
0/1†
3
9
1
4
0
29/4†
17/1†
1/1†
0
3
1
3/15†
0
4
0
4/1†
2
0
44¶/1†
150/24†
174

31
2/4†
7
7
2
5
0
29/7†
10/11†
5
1
5
6
3/45†
4
3
0/2†
4/1†
7
0
68*/3†
199/73†
272

22
2
3
13
4/1†
2
0
48/4†
11/16†
3/1†
0
6
13
1/56†
2/1†
2
21
2
6
0
57*/2†
218/81†
299

Total
237
49/8†
42/1†
63/1†
91/3†
24/2†
0
564/120†
395/56†
74/7†

237
57
43
64
94
26
0
684
451
81

8
7
9/1†

26/1†
34/2†
35/4†

27
36
39

4/34†
3/1†
3/1†
8
0
7
0
33/4†
267/63†
330

67/182†
9/3†
78/3†
53/99†
20/3†
31/2†
17
227/11†
2,136/508†
2,644

249
12
81
152
23
33
17
238
2,644

Abbreviations: ACIP = Advisory Committee on Immunization Practices; Hib = Haemophilus influenzae type b; HPV = human papillomavirus.
* Includes years when monthly or quarterly immunization tables were printed.
† Cases from United States or US leads/cases from other countries or reported globally.
§ Hepatitis, other indicates viral hepatitis, hepatitis not otherwise specified, non-A non-B hepatitis, or hepatitis C.
¶ Other includes vaccination coverage surveys or multidisease or combination vaccine articles.

56

MMWR  /  October 7, 2011  /  Vol. 60

Grand total

30
0
8
7/1†
10
5/1†
0
104/3†
9/17†
12

Supplement

a strong vaccine-delivery system in both public and private
sectors, while ensuring adequate surveillance of disease and of
vaccine coverage. Key opportunities for future progress in the
United States include improved access to preventive services,
such as vaccines among adults through implementation of the
Patient Protection and Affordable Care Act of 2010, and performance improvements and efficiency that should result from
enhanced interoperability of IIS and electronic health records.
The health and economic benefits of vaccines and immunization already evident in wealthier countries are potentially
achievable throughout the world through the introduction of
new and underused vaccines reaching the 20% of children not
yet covered through routine immunization efforts, and effectively integrating other interventions into routine immunization services. Research advances may bring new transformative
interventions, such as an effective malaria vaccine, during what
Bill Gates has dubbed the Decade of the Vaccine (27). The
future could also implement a key lesson learned from the
outbreak of 2009 pandemic influenza A (H1N1) by investing
in innovative technologies that will permit faster production of
large quantities of influenza vaccine, which could improve the
effectiveness of response to the next influenza pandemic and
improve the control of seasonal influenza. In future decades,
the long-term benefits of vaccinating girls against human
papillomavirus, both in developed countries and around the
world, should be manifested by major reductions in cervical
cancer and its precursors. Successful eradication of polio in the
remaining reservoir countries will be a permanent gift from
this generation to all future ones.
References
1. Hinman AR. Immunizations and CDC. Proceedings of the 30th
Immunization Conference, Washington, DC, April 9, 1996. Atlanta,
GA: US Department of Health and Human Services, CDC;1996: 7-13.
2. Sencer DJ, Dull HB, Langmuir AD. Epidemiologic basis for eradication
of measles in 1967. Public Health Rep 1967;82:253–6.
3. CDC. Advisory Committee on Immunization Practices (ACIP).
Available at http://www.cdc.gov/vaccines/recs/acip/default.htm.
4. Smith JC, Snider DE, Pickering LK, Advisory Committee on
Immunization Practices. Immunization policy development in the
United States: the role of the Advisory Committee on Immunization
Practices. Ann Intern Med 2009;150:45–9.
5. Davis RL, Kolcazk M, Lewis E, et al. Active surveillance of vaccine safety:
a system to detect early signs of adverse events. Epidemiology 2005;​
16:336–41.

6. Orenstein WA. The role of measles elimination in development of a
national immunization program. Pediatr Infect Dis 2006;25:1093–101.
7. The National Vaccine Advisory Committee. The measles epidemic: the
problems, barriers and recommendations. JAMA 1991;266:1547–52.
8. Santoli JM, Rodewald LE, Maes EF, Battaglia MP, Coronado VG.
Vaccines for Children program, United States, 1997. Pediatrics
1999;104:e15.
9. CDC. Status report on the Childhood Immunization Initiative: national,
state, and urban area vaccination coverage levels among children aged
19–35 months—United States, 1996. MMWR 1996;46:657–64.
10. Adams WG, Deaver KA, Cochi SL, et al. Decline of childhood
Haemophilis influenzae type b (Hib) disease in the Hib vaccine era. JAMA
1993;269:264–6.
11. CDC. Vaccination coverage in the U.S. Available at http://www.cdc.
gov/vaccines/stats-surv/imz-coverage.htm.
12. Alexander LN, Seward JF, Santibanez TA, et al. Vaccine policy changes
and epidemiology of polio in the United States. JAMA 2004;​
292:1696–701.
13. CDC. Intussusception among recipients of rotavirus vaccine—United
States, 1998–1999. MMWR 1999;48:577–81.
14. CDC. Notice to Readers. Thimerosal in vaccines: a joint statement of
the American Academy of Pediatrics and the Public Health Service.
MMWR 1999;48:563–65
15. Thompson WW, Price C, Goodson B, et al. Early thimerosal exposure
and neuropsychological outcomes at 7 to 10 years. N Engl J Med 2007;​
357:1281–92.
16. CDC. Direct and indirect effects of routine vaccination of children with
7-valent pneumococcal conjugate vaccine on incidence of invasive
pneumococcal disease—United States, 1998–2003. MMWR 2005:​
54:893–7.
17. Office of Disease Prevention and Health Promotion, US Department
of Health and Human Services. Healthy people 2010. Objective 14-24a,
Available at http://www.healthypeople.gov/2010/document/html/
objectives/14-24.htm.
18. CDC. Ten great public health achievements—United States,
2001–2010. MMWR 2011;60;619–23.
19. Schuchat A, Bell BP. Monitoring the impact of vaccines post-licensure:
new challenges, new opportunities. Expert Rev Vaccines 2008;7:437–56.
20. Sugarman DE, Delea MG, Ortega-Sanches IR, et al. Measles outbreak
in a highly vaccinated population, San Diego, 2008: role of the
intentitonally undervaccinated. Peditarics 2010;125:747–55.
21. CDC. Provider resources for vaccine conversations with parents.
Available at www.cdc.gov/vaccines/conversations.
22. Strikas RA, Rotz L, Cono J, Knutson D, Henderson J, Orenstein WA.
US civilian preparedness and response smallpox program. Clin Infect
Dis 2008:46(Suppl 3):S157–67.
23. CDC. Interim results: state-specific influenza A (H1N1) 2009
monovalent vaccination coverage—United States, October 2009–
January 2010. MMWR 2010;59:363–8.
24. CDC. Safety of influenza A(H1N1) 2009 monovalent vaccines—United
States, October 1–November 24, 2009. MMWR 2009;58:1351–6.
25. CDC. Global measles mortality, 2000–2008. MMWR 2009;​58:1321–6.
26. Global Polio Eradication Initiative. Available at www.polioeradication.org.
27. Bill & Melinda Gates Foundation. Bill and Melinda Gates pledge $10
billion in call for Decade of Vaccines. Available at http://www.
gatesfoundation.org/press-releases/Pages/decade-of-vaccines-wecannouncement-100129.aspx.

MMWR  /  October 7, 2011  /  Vol. 60

57

Supplement

Control of Health-Care–Associated Infections, 1961–2011
Richard E Dixon, MD
Health Net of California, Rancho Cordova, California
Corresponding author: Richard E. Dixon, MD, Regional Medical Director; Health Net of California, Inc., 11971 Foundation Place; Rancho Cordova, CA
95670; Telephone: 916-935-1941; Fax 800-258-3506; E-mail: [email protected].

Introduction
For centuries, hospitals have been known as dangerous
places. In 1847, Ignaz Semmelweis presented evidence that
childbed fever was spread from person to person on the unclean
hands of health-care workers (1). Semmelweis’s findings did
not immediately improve sanitary conditions in hospitals, but
surgeons gradually adopted aseptic and antiseptic techniques
and became leading innovators of techniques to reduce patients’
susceptibility to postoperative infections. Concerns about the
spread of infection by air, water, and contaminated surfaces
gradually changed practices in hospitals, making them safer.
During the 1950s, epidemic penicillin-resistant Staphylococcus
aureus infections, especially in hospital nurseries, captured the
public’s attention and highlighted the importance of techniques
to prevent hospital-acquired infections, now also referred to
as health-care–associated infections (HAIs; i.e., nosocomial
infections) (2). By the mid-20th century, some surgeons,
microbiologists, and infectious disease physicians had focused
their studies on the epidemiology and control of HAIs (3,4).
From the efforts of these pioneers grew the notion that hospitals had the ability—and the obligation—to prevent HAIs.
By the 1960s, hospital-based infection control efforts had
been established in scattered hospitals throughout the United
States. The number of hospitals with HAI control programs
increased substantially during the 1970s, and HAI control
programs were established in virtually every U.S. hospital
by the early 1990s. The remarkable spread and adoption of
programs designed to prevent and control HAIs hold valuable
lessons about the ways that other public health initiatives can be
designed, developed, and implemented. This report traces the
strategic and tactical steps used to bring about a major public
health success: the ubiquity of formal established infection
control programs in virtually all U.S. hospitals and expanding
into other health-care settings.

Developing the Public Health Model
for Hospital Infection Control
By the late 1950s and early 1960s, a small proportion of
hospitals had begun to implement programs designed to
understand and control HAIs. The pioneering leaders of those
58

MMWR  /  October 7, 2011  /  Vol. 60

efforts were located mostly in large, academic medical centers,
not in public health agencies. Although state, local, and federal
public health agencies were sporadically called on to provide
epidemiologic or laboratory support to investigate particular
problems, they did not consider hospitals as communities
needing ongoing public health resources. Nor did hospitals
routinely see themselves as communities needing such assistance. During the 1950s and even afterwards, many hospitals
saw themselves as “the doctor’s workshop” and their roles as
providers of space and personnel to support practicing physicians. In most communities, a hospital was perceived as good
because doctors who practiced there were perceived as good,
not because the hospital’s outcomes were better than its competitors’. Focused on patients and doctors as individuals, most
hospitals neither tracked nor had systems in place designed
to improve their overall outcomes; public health–based and
population-based principles often were not important management priorities. The nosocomial staphylococcal epidemics of
the 1950s began to change those attitudes.
History did not record who first understood—or when it
was first recognized—that hospitals are discrete communities
in which public health principles could be used to prevent and
control HAIs. But by the 1960s, hospital-based clinicians and
CDC epidemiologists clearly were beginning to apply a public
health model to HAIs. That model was built around systematic
surveillance to identify HAIs; ongoing analysis of surveillance
data to recognize potential problems; application of epidemic
investigation techniques to epidemic and endemic HAIs;
and implementation of hospitalwide interventions to protect
patients, staff, and visitors who seemed to be at particular risk.
One might assume that the public health system would
have managed the public health approach to HAIs. It did
not. Instead, a different approach evolved. Hospitals built
and managed their own infection control programs. The historical record is murky as to why infection control programs
became the responsibility of hospitals, rather than local, state,
or national public health agencies. Although many exceptions
certainly existed, hospitals generally did not work closely with
their local health departments, and when they did interact,
the health departments were sometimes seen to be regulators,
not colleagues. A perception at the time was that most health
departments had little interest in the hospitals’ clinical activities.

Supplement

Given the absence of a tradition of collaboration between
community hospitals and local health departments, two of
CDC’s first public health research and development activities
were embedded in hospitals themselves. One was a national
network of hospitals that volunteered to conduct HAI surveillance by using CDC methods and to report those data to CDC
each month. That voluntary surveillance system, the National
Nosocomial Infection Surveillance program, has changed over
the years but remains active as the National Healthcare Safety
Network (NHSN; http://www.cdc.gov/nhsn/) and continues
to provide information about the changing patterns of HAIs.
The second of CDC’s research projects also was located in
community hospitals, and it profoundly affected the evolution
of infection control programs. The Comprehensive Hospital
Infections Project (CHIP) was begun in 1965 (5). Eight community hospitals, which were located in different cities across
the country, participated in the project. Those hospitals served
as the laboratories where surveillance and control techniques
were developed. CDC funded those activities, and Atlantabased CDC staff actively collaborated in the research. Physician
and nurse epidemiologists, along with CDC microbiologists,
visited CHIP hospitals regularly and conducted studies to learn
the epidemiology of HAIs. CHIP studies helped to define how
HAIs could be identified and distinguished from communityacquired infections. Hospital staff and CDC epidemiologists
explored what data were needed to improve practices and how
those data should be analyzed and reported. That direct field
epidemiology experience gave CDC important insights into
the ways that community hospitals worked. The close interactions with the hospitals undoubtedly helped CDC develop
unique recommendations that were credible to hospitals and
practical for them to use.
CDC’s decision to use community hospitals for some of
its early research was a strategic one. Most hospital inpatients
were—and still are—treated in community hospitals. Although
CDC staff interacted closely and shared ideas with leading
infectious disease experts in the United States and Europe,
CDC’s involvement with community hospitals made the
resulting infection control models and techniques more likely
to be appropriate for use in the kinds of institutions where
most patients get hospital care.

Promoting the Public Health Model
to All U.S. Hospitals
As the infection control community developed confidence
in the value of infection control programs, the next task was to
assist other hospitals to adopt them voluntarily. Two barriers
were obvious. First, hospitals were not required to have such

programs, so the value of the activities had to be promoted
to hospital administrators and clinical staffs. Because they
recognized such programs as advantageous to the hospital and
its patients, many hospitals voluntarily adopted and paid for
such programs.
The second problem posed a larger challenge. Because local
and state health departments did not have the resources to
place their personnel in every hospital needing an infection
control program, where would the trained infection control
specialists come from? Existing hospital personnel had to be
recruited and trained to use entirely new public health and
epidemiologic skills.
The new jobs were often filled by existing staff nurses and
laboratorians who built new careers as infection control practitioners (ICPs). The ICPs usually were supervised by hospital
epidemiologists—typically physicians selected from the existing medical staff, such as pathologists or infectious disease–
trained physicians. These doctoral-level program directors
often were hired to provide this service part time, and many
volunteered to serve without pay. Both positions—ICP and
hospital epidemiologist—were newly created positions, and at
the time, few ICPs or hospital epidemiologists had more than
cursory formal training in epidemiology or any other public
health discipline.
Training for these new careers often took place informally,
on the job, by networking with colleagues in other hospitals,
and by taking brief training courses. Many of the pioneer
infection control programs were staffed by practitioners who
had either attended a week-long training course conducted at
CDC or had been trained by another practitioner who had
been trained at CDC. As a result, the knowledge and attitudes of the earliest infection control staff had considerable
uniformity. Those pioneers soon became the leaders of their
new fields and naturally became the teachers and consultants
for new practitioners. The public health model became an
unofficial standard of practice; it focused on active prospective
surveillance, data analysis, and reporting, and it emphasized
prevention programs that relied on the education of hospital
staff about infection control techniques.
Although using existing hospital staff and retraining them for
their new jobs provided many advantages, this practice also had
unanticipated disadvantages. Few infection control pioneers
brought investigative experience to their new positions. As a
result, when problems were discovered by surveillance, instead
of basing interventions on locally acquired epidemiological and
laboratory evidence, often they were based merely on established
guidelines and recommendations that seemed logically to make
the most sense. The evidence base for many of those guidelines
was not strong, however, because effectiveness studies of intervention programs had rarely been conducted.
MMWR  /  October 7, 2011  /  Vol. 60

59

Supplement

Infection Control Becomes a
Profession

Transforming Infection Control from
Movement to Mandate

The rapid growth and acceptance of infection control
programs was undoubtedly stimulated by the new career possibilities offered by the emerging infection control field. Staff
nurses, microbiologists, pathologists, and infectious disease
clinicians were eager to become part of a field that provided new
skills and offered new opportunities. The professionalization
of infection control practice was strengthened when, in 1972,
infection control practitioners formed a professional society,
the Association of Practitioners in Infection Control (APIC,
now the Association for Professionals in Infection Control and
Epidemiology). APIC was formed to provide practitioners with
continuing professional interaction, education, and growth. A
certifying program based on practitioners’ education, experience, and test scores followed in 1980, further establishing
infection control as an attractive career.
The hospital epidemiologists followed soon afterwards in
forming their own professional society, the Society of Hospital
Epidemiologists of America (SHEA), now The Society for
Healthcare Epidemiology of America. Its initial membership
requirements allowed only physicians to join, and physician
infectious disease subspecialists accounted for most of its
early members. Only several years after its founding were
nonphysician epidemiologists, sanitarians, microbiologists,
and other doctoral-level practitioners able to join SHEA. The
doctoral-level societies were also divided. Surgeons interested
in hospital-acquired infections formed their own society: the
Surgical Infection Society (SIS). SIS, like the other professional
associations, has expanded membership to other categories
of physicians, nurses, and others with an interest in surgical
infections. SIS, SHEA, and APIC have not merged, although
they have developed collegial working relationships and have
important collaborations.
Although the development of trained professional cadres of
infection control experts in every hospital seems to be an obvious benefit, it must be asked whether infection control would
have been more innovative and might have advanced faster if the
practitioners of the new careers had welcomed other disciplines
and other kinds of expertise into the field earlier. Would that have
promoted innovation? Would it have led to faster development of
an evidence base for infection control? Perhaps so. Public health
officials need also to consider this question as they develop and
deploy new approaches to public health practice.

By the late 1970s, the infection control field was well established. It had strong presences in hospitals across the country,
organized work forces, a coherent model that guided the field’s
activities, and a rapidly expanding body of scientific publications. A decade earlier, during the late 1960s and early 1970s,
however, that degree of success was not certain. During the
early 1970s, the hospital infection control movement faced the
same challenges as many other public health initiatives have
before it: how to increase adoption by more communities and
how to convert a good idea into a virtual mandate for action.
By the mid-1970s, HAIs were recognized as a major threat
associated with medical care. Despite the increasing public and
professional concern about HAIs, it became apparent during
the mid-1970s that not all hospitals were adopting infection
control programs. CDC had ready access to national professional societies, health-care trade associations, accrediting
organizations, and regulatory agencies, but infection control
programs, although encouraged, were not mandated. Some
hospitals had no programs at all. Other hospitals had programs,
but no requirement existed to ensure they were properly staffed,
well structured, or effective. The absence of a requirement that
hospitals have effective infection control programs to protect
the public was due, in part, to the fact that the evidence for the
effectiveness of the public health model for infection control
programs was mostly only anecdotal. It had a compelling story;
it seemed like a good thing to do; but it was not evidence based.
CDC determined that a rigorous scientific assessment of the
effectiveness of infection control programs would be necessary
to propel widespread adoption of hospital-based programs. That
decision led to the Study on the Effectiveness of Nosocomial
Infection Control (SENIC), a rigorous assessment of infection
control effectiveness that compared outcomes in hospitals with
and without CDC-style infection control programs (6). The
study was designed to determine whether infection control
programs using CDC-recommended practices actually reduced
the risks from HAIs. To conduct the study, 338 U.S. hospitals
were randomly selected and were stratified by geography, inpatient bed capacity, and teaching status. Approximately half of
the study hospitals had established infection surveillance and
control programs. When that study showed that hospitals with
infection control programs had significantly lower rates of
HAIs than did hospitals without such programs (7), expectations for hospital programs changed. With strong scientific
evidence supporting the value of such programs, accrediting
organizations such as the Joint Commission on Accreditation of
Hospitals (now The Joint Commission) mandated that accredited hospitals have infection control programs similar to those

60

MMWR  /  October 7, 2011  /  Vol. 60

Supplement

recommended by CDC and the professional organizations of
hospital epidemiologists and infection control practitioners.
The Joint Commission made this an accreditation requirement
in 1976 (8).
The SENIC study converted a movement into a mandate.
Although it is widely agreed that new treatment interventions
for individual patients should be tested in rigorous clinical
trials, such trials are much less common for large populationbased interventions. The design and conduct of assessments for
population-based interventions can be difficult scientifically,
legally, and ethically. They also can be expensive, and often
no commercial company is interested enough to sponsor such
studies. As a result, SENIC-style studies are rarely conducted
by public health agencies.
Beyond its revolutionary effect on infection control practices in hospitals, the SENIC study served as an example that
rigorously conducted public health research can change the
credibility and acceptability of public health interventions
and can speed adoption of important programs. It established
how, when a public health problem is important enough, a
scientifically rigorous population-based assessment can be used
to propel the implementation of effective programs. In the
future, public health programs are likely to face ever-greater
demands for proof of worth and more competition for support,
and more SENIC-style studies may be needed.

Hospital Epidemiology in the New
Century
CDC continues to play an important role in HAI prevention
research. CDC’s Division of Healthcare Quality Promotion
(DHQP) has substantial expertise in HAI control, stemming
in part from decades of experience in HAI epidemiologic investigations. That, along with its central role in the public health
infrastructure, gives CDC a unique opportunity and responsibility to guide and support research that directly addresses the
knowledge gaps most relevant to the public health.
In addition to the important research contributions that arise
directly from the core activities of outbreak investigation, laboratory support, and HAI surveillance, CDC dedicates funds
for innovative extramural HAI prevention research through its
Prevention Epicenter Program. DHQP began the Prevention
Epicenters Program in 1997 as a way to work directly with academic partners to address important scientific questions about
the prevention of health-care–associated infections, antibiotic
resistance, and other adverse events associated with health
care. Through a collaborative funding mechanism, DHQP
staff work closely with a network of academic centers to foster
research on the epidemiology and prevention of HAI, with

an emphasis on multicenter collaborative research projects.
The program has provided a unique forum in which leaders
in health-care epidemiology can collaborate with each other
and with CDC to pursue innovative research endeavors that
bring into alignment both academic and public health research
goals and objectives and create important synergies that might
not be possible for a single academic center or without the
benefit of cross-fertilization of ideas between academic and
public health experts.
Research conducted through the Epicenters program has
produced valuable contributions to the field and to the mission of DHQP. The program has resulted in approximately
150 peer-reviewed publications that cover a broad array of
topics relevant to HAI prevention, including the epidemiology of infections caused by multidrug-resistant organisms
and Clostridium difficile; development and testing of novel
prevention strategies, such as the use of chlorhexidine bathing
to prevent bloodstream infections and pathogen transmission
among intensive-care unit patients; and development of novel
HAI surveillance strategies that are helping to shape the future
of HAI surveillance through the National Healthcare Safety
Network. CDC should seek to maintain an active participatory
role in HAI research.
As CDC plans its research agenda, another lesson taught
by the development of infection control as a public health
discipline should be remembered: sometimes public health
agencies need to actually conduct research, not just fund it.
CDC’s credibility obtained through its own research was an
essential factor in its ability to promote infection control programs. Working in hospitals, collecting data, and conducting
field studies alongside hospital workers gave CDC a unique
understanding of the challenges that hospital-based infection
control personnel face. As a result, CDC recommendations
were more likely to be useful and appropriate than they would
have been had CDC simply funded others to do its research.
Learning the subtleties of what did not work or what was
impractical to implement was perhaps more important than
learning what did work, and this was learned best by the agency
conducting the research itself.
The landscape of infection control and health-care epidemiology began another dramatic shift with the publication of
the Institute of Medicine (IOM) report, To Err is Human, in
1999 (9). This report revealed that thousands of patients in
U.S. hospitals were injured or died each year because of medical
errors—many of which might have been preventable. HAIs
were recognized as a leading cause of these preventable harms.
This report was followed by an influential series of investigative articles on health-care–associated infections published by
the Chicago Tribune. These reports underscored the findings
of the IOM report on the major public health effects of HAIs
MMWR  /  October 7, 2011  /  Vol. 60

61

Supplement

and criticized hospitals for failing to prevent these infections
and keeping secret the scope of the problem. The IOM report
and Chicago Tribune articles touched off an active debate
about HAI prevention and spurred action by consumers and
legislatures. In 2002, four states (Illinois, Florida, Missouri,
and Pennsylvania) passed laws to mandate that health-care
facilities report HAIs to the public. Proponents of the legislation argued that health-care facilities would finally begin to
take real steps toward preventing HAIs if they had to disclose
them more openly.
Public interest in HAIs reached an important tipping point
in 2005–2006 with the publication of two studies about the
prevention of central line–associated bloodstream infections
(CLABSIs). One study was a collaboration between CDC and
the Pittsburgh Regional Healthcare Initiative and the other a
collaboration between researchers at Johns Hopkins University
Hospital and the Michigan Hospital Association (10,11).
Both studies brought together staff from a large number of
intensive-care units who collaborated to reduce CLABSIs by
implementing a relatively simple set of interventions. The
results of the studies were striking and consistent. In each,
CLABSIs were reduced by roughly 65%.
Increasing awareness of the scope of the HAI problem,
coupled with the recognition that a substantial portion of
these infections could be prevented, galvanized even more
consumers and policy makers to take action. Many other state
legislatures began to debate and pass laws to mandate the public
reporting of HAIs. In recognition of the growing interest in
so-called public reporting, CDC worked with the Healthcare
Infection Control Practices Advisory Committee to develop
recommendations to help guide future legislation (12). These
laws have now become widespread. Twenty-eight states have
passed legislation that requires the public reporting of one or
more HAIs, and legislation is pending in others. Federal lawmakers also have taken up the HAI issue. In 2008, as part of
the larger deficit-reduction act, Congress mandated that the
Center for Medicare and Medicaid Services (CMS) stop giving
hospitals increased payments for the care of patients with HAIs.
CMS worked closely with CDC to identify HAIs that were
“reasonably preventable” to support implementation of this
requirement. In 2010, Congress incorporated HAI prevention
into the Value Based Purchasing program of the Affordable
Care Act. CMS has elected to implement the requirement by
requiring national public reporting of HAIs, beginning with
CLABSIs in 2011.
CDC is playing a central role in supporting legislative mandates on HAI reporting and prevention. Laws in 22 of the 28
states that require reporting of HAIs specifically stipulate that
facilities use the CDC’s NHSN as the platform for that reporting. Likewise, the new CMS mandate will require submission
62

MMWR  /  October 7, 2011  /  Vol. 60

of data to NHSN. These requirements have led to a dramatic
expansion in NHSN enrollment, from roughly 300 hospitals
in 2006 to approximately 3,500 in 2010. Increasingly, state
health departments, with support from CDC, are leading
HAI prevention efforts. Their role in HAI prevention was
recognized and greatly enhanced in 2009 with passage of the
American Recovery and Reinvestment Act. That legislation
included $50 million to support state-based HAI prevention
efforts. American Recovery and Reinvestment Act funds were
distributed through CDC’s Epidemiology and Laboratory
Capacity grant to support state efforts to build HAI infrastructure and expand surveillance and prevention efforts. CDC
staff and experts are now supporting HAI prevention efforts in
49 funded states, the District of Columbia, and Puerto Rico.
Specifically, CDC subject-matter experts are helping guide
the expansion and validation of HAI surveillance data and the
initiation and expansion of HAI prevention.

Conclusions
Efforts to prevent and control HAIs have led to profound
changes in the ways that those infections are perceived and
managed in the United States and abroad. Programs focused
on preventing and controlling HAIs were rare in U.S. hospitals in the early 1970s; now, they are present in virtually every
hospital in the nation and in many hospitals abroad.
Among the main factors that led to this success was, most
importantly, CDC’s decision to use a rigorous scientific study, the
SENIC study, to demonstrate that infection control programs
were effective. This evidence obtained from SENIC converted
infection control programs from being something worth doing
into programs that must be implemented to reduce illness and
death. Before SENIC, the evidence for the effectiveness of infection control programs was insufficient to make these programs
mandatory. With evidence from SENIC, it was virtually impossible for hospitals to avoid implementing them.
CDC’s ability to work with others to design and refine infection control programs was almost certainly aided by CDC’s
direct field experience investigating epidemics. Perhaps even
more important was CDC’s experience working directly with
hospitals over a long period to design and test surveillance and
control techniques. That first-hand field epidemiology helped
CDC to learn how hospitals function and to design infection
control programs that were practical and could be implemented.
CDC and other pioneers helped to define a new field (hospital epidemiology) and new professional disciplines (infection
control and hospital epidemiology). When no training courses
or job descriptions existed for those essential hospital workers,
CDC provided the key early training and job-development

Supplement

resources used by a large proportion of infection control
pioneers. Because of CDC’s early dominance in defining
the work of these new disciplines, CDC profoundly affected
knowledge base, work activities, and extent of the practitioners’
responsibilities.
Finally, hospital epidemiology was, for many years, a misleading title for a field that mainly focused on HAIs. As the
patient safety movement has vividly shown, the opportunities
for strong public health skills in hospitals extend far beyond
mere infection control. CDC has the capacity to continue to
support that effort and thereby help prevent the range of errors,
omissions, and other preventable mishaps that still plague the
organizations that should heal, not harm.
References
1. Semmelweis I. Etiology, concept and prophylaxis of childbed fever.
Madison, WI: University of Wisconsin Press; 1983.
2. Wise RI, Ossman EA, Littlefield DR. Personal reflections on nosocomial
staphylococcal infections and the development of hospital surveillance.
Med J Aust 1978;12:543–6.
3. Finland M, McGowan JE Jr. Nosocomial infections in surgical patients.
Observations on effects of prophylactic antibiotics. Arch Surg 1976;​
111:143–5.

4. McGowan JE Jr, Barnes MW, Finland M. Bacteremia at Boston City
Hospital: occurrence and mortality during 12 selected years (1935–
1972), with special reference to hospital-acquired cases. J Infect Dis
1975;132:316–35.
5. CDC. Nosocomial infections in community hospitals, report no. 4, July
1968–1969. Atlanta, GA: US Department of Health, Education, and
Welfare, CDC; 1969.
6. Haley RW, Quade D, Freeman HE, et al. The SENIC project: Study
on the Efficacy of Nosocomial Infection Control (SENIC PROJECT):
summary of study design. Am J Epidemiol 1980;111:472–85.
7. Haley RW, Culver DH, White JW, et al. The efficacy of infection
surveillance and control programs in preventing nosocomial infections
in US hospitals. Am J Epidemiol 1985;121:182–205.
8. Weinstein RA. Nosocoomial infection update. Emerg Infect Dis 1998;​
4;416–20.
9. Institute of Medicine. To err is human: building a safer health system.
Washington, DC: National Academies Press; 2000.
10. CDC. Reduction in central line--associated bloodstream infections
among patients in intensive care units—Pennsylvania, April 2001–March
2005. MMWR 2005;54:1013–6.
11. Pronovost P, Needham D, Berenholtz S, et al. An intervention to decrease
catheter-related bloodstream infections in the ICU. N Engl J Med 2006;​
355:2725–32.
12. McKibben L, Horan T, Tokars JI, Guidance on public reporting of
healthcare-associated infections: recommendations of the Healthcare
Infection Control Practices Advisory Committee. Am J Infect Control
2005;33:217–26.

MMWR  /  October 7, 2011  /  Vol. 60

63

Supplement

AIDS: the Early Years and CDC’s Response
James W. Curran, MD1
Harold W. Jaffe, MD2
1Rollins School of Public Health, Emory University, Atlanta, Georgia
2Office of the Director, CDC, Atlanta, Georgia
Corresponding author: James W. Curran, MD, Rollins School of Public Health, Emory University, 1518 Clifton Road, NE, Room 8011, Atlanta, GA 
30322; Telephone: 404-727-8720; Fax 404-712-8879; E-mail: [email protected].

Initial Reports
The MMWR description of five cases of Pneumocystis carinii
pneumonia (PCP) among homosexual men in Los Angeles was
the first published report about an illness that would become
known as acquired immunodeficiency syndrome (AIDS) (1).
Appearing 4 months before the first peer-reviewed article
(2), the timeliness of the report can be credited to the astute
clinical skills and public health sensitivity of Dr. Michael
Gottlieb and his colleagues at the University of California, Los
Angeles, School of Medicine and Cedars-Sinai Hospital, who
worked closely with Dr. Wayne Shandera, the CDC Epidemic
Intelligence Service (EIS) officer assigned to the Los Angeles
County Department of Health Services.
The Parasitic Diseases Division of CDC’s Center for
Infectious Diseases already had become concerned about
other reports of unusual cases of PCP. The Division housed
the Parasitic Disease Drug Service, which administered the
distribution of pentamidine isethionate for PCP treatment.
Because PCP was rare and pentamidine was not yet licensed
in the United States, it was available only from CDC. A review
of requests for pentamidine had documented that PCP in the
United States was almost exclusively limited to patients with
cancer or other conditions or treatments known to be associated with severe immunosuppression (3). Recent requests for
this drug from physicians in New York and California to treat
PCP in patients with no known cause of immunodeficiency
had sparked the attention of Division staff.
Shortly after the first report, additional cases of other lifethreatening opportunistic infections (OIs) and a malignancy,
Kaposi sarcoma (KS), were reported (4). After learning of
these first cases, CDC, under the leadership of its Director,
Dr. William Foege, formed a Task Force on Kaposi’s Sarcoma
and Opportunistic Infections to begin surveillance and conduct
epidemiologic investigations. Despite the fiscal constraints
at the time, approximately 30 CDC EIS officers and staff
participated in the Task Force during the summer of 1981.
The first step for the Task Force was to establish a case definition for surveillance and investigation of the outbreak. The key
underlying factor for the disease appeared to be severe suppression of the cellular immune system. The OIs initially reported

64

MMWR  /  October 7, 2011  /  Vol. 60

were life-threatening and often fatal. Although KS was a known
but infrequent cancer in the United States, the classical form
of the disease was rarely life-threatening and typically occurred
among elderly men. Another epidemiologic form of KS was
seen among immunosuppressed renal transplant recipients.
To track KS/OI, the surveillance case definition had to
emphasize specificity and accuracy of diagnosis. Thus, the
original CDC case definition included 1) biopsy-proven KS
among persons <60 years of age or biopsy- or culture-proven
life-threatening or fatal OIs and 2) no known underlying
illness (e.g., cancer or immune deficiency disease) or history
of immunosuppressive therapy. This definition was soon
adopted both in the United States and worldwide and was
used for surveillance in countries where diagnostic capacities
were available. The CDC case definition for what came to be
called AIDS was modified in 1985 (5), 1987 (6), and 1993
(7). The World Health Organization employed a modified case
definition for use in settings with limited diagnostic capacity
(usually developing countries).
By the end of 1981, 159 cases of KS and OIs had been
reported in the United States, with the earliest cases retrospectively identified in 1978 (8). By month of illness onset,
cases demonstrated a clear increase over time (Figure 1).
About half of the reports were for KS alone and 40% for PCP
alone; 10% of patients were reported with both KS and PCP.
Seventy-five percent of cases were reported from New York
City or California, and all but one case were in men. Within 6
months, it was clear that a new, highly concentrated epidemic
of life threatening illness was occurring in the United States.
The co-occurrence of KS and OIs suggested that the epidemic
was one of immunosuppression and that KS or OIs were a
consequence of the immunosuppression.
Although the case definition’s specificity was crucial for identifying the emerging epidemic, it lacked sensitivity. In fact, the
reported KS/OI cases were described as “the tip of the iceberg”
of a spectrum of illness being seen by physicians in New York
City and California. These illnesses included other cancers
(particularly non-Hodgkin lymphoma); thrombocytopenic
purpura; and notably, persistent, unexplained generalized
lymphadenopathy. Dr. Donna Mildvan and her colleagues
in New York City, assisted by EIS officer, Dr. Bess Miller,

Supplement

FIGURE 1. Incidence of Kaposi’s Sarcoma (KS), Pneumocystis carinii
Pneumonia (PCP), and other opportunistic infections — United
States, 1979–1981

Source: Epidemiologic aspects of the current outbreak of Kaposi’s sarcoma and
opportunistic infections. N Engl J Med 1982;306:248–52. Reprinted with
permission.

described 57 cases of unexplained lymphadenopathy among
gay men (9). At the time, nearly one third of the reported
persons with KS had a history of such lymphadenopathy.
Since lymphadenopathy and other symptoms often waxed
and waned, it was speculated that such findings represented a
milder, if much more common, form of the syndrome.
Early in 1982, CDC conducted a national case–control study
that included most living patients with KS/OIs reported in the
United States. The 50 cases among gay men were compared
with control gay men matched by city of residence, race, and
age. The studies, led by Drs. Harold Jaffe and Martha Rogers,
found that case-patients tended to be much more sexually
active than controls and were more likely to have had other
sexually transmitted infections (10,11).
In early 1982, Dr. David Auerbach, the EIS officer who
had replaced Dr. Shandera in Los Angeles, was approached
by a member of the local gay community about a possible
sexual link between the still rare cases in southern California.
In collaboration with Dr. William Darrow of the Task Force,
Dr. Auerbach investigated 13 of the first 19 cases reported
from Los Angeles and Orange counties and found that nine
had reported sexual contact with another person reported
with AIDS within 5 years before their onset of symptoms
(12). Auerbach and Darrow then extended the epidemiologic
investigation nationwide to 90 patients (approximately three
quarters of reported cases among gay men alive at the time).
Forty of the 90 patients in 10 cities were linked by sexual
contact with another case-patient (13). These findings, along
with the results from the case–control study, strongly suggested
that the new syndrome was caused by a sexually transmissible
infectious agent. Nonetheless, whether because of competing
hypotheses or merely denial, many scientists and the public
were skeptical of the infectious agent causation theory.

Then, in early summer 1982, an elderly man with severe
hemophilia A was reported to have died from PCP. Shortly
thereafter, two additional PCP cases were reported among
young men with severe hemophilia from separate states. These
latter cases were investigated in depth by Dr. Dale Lawrence
of the Task Force, who determined that their PCP was accompanied by severe unexplained immunosuppression, and these
patients had no history of homosexual contact or needle sharing
(14). For more than a decade, persons with hemophilia in the
United States had received reconstituted lyophilized clotting
factor concentrates, derived from human plasma, to prevent the
devastating effects of their disease. However, the concentrates
were pooled from the plasma of >1,000 donors per lot and
were known to transmit hepatitis viruses.
Within the next several months, AIDS cases also were
reported among infants (15–17), female sex partners of men
with, or at high risk for, AIDS (18,19), and an infant and adults
who had received blood transfusions (20,21). Taken together,
these cases provided strong evidence that AIDS was caused
by an infectious agent that could be transmitted by blood
and from mother to child, as well as through homosexual and
heterosexual contact.
In the summer of 1982, life-threatening OIs and KS were also
reported among 34 Haitian migrants to the United States (22).
Most were reported to be heterosexual men with no known
risk factors who had migrated from Haiti within the past 2
years. Cases of disseminated KS had been recently reported
from Port-Au-Prince as well (23). These reports indicated an
epidemiologically distinct pattern of illness that ultimately
would be explained mostly by heterosexual transmission. The
reporting of these cases as “Haitian entrants” was accurate and,
these authors believe, necessary for public health purposes, but
the stigma of “AIDS labeling” added to the already considerable
burden for thousands of Haitian migrants fleeing poverty and
political persecution (24).

Recommendations for Prevention
During the initial year after the first reports of AIDS, when
the term “gay plague” was commonly used, the disease received
relatively little attention from the mainstream media, the public, or politicians. By the end of 1982, however, it was clear
that others were at risk for the disease, and what had been
complacency turned into serious concern, even panic. Many
persons caring for AIDS patients were concerned about their
own safety and, in some cases, health-care workers refused
to provide needed care. To provide guidance for protection
of clinicians and laboratory workers managing patients with
AIDS and their biologic specimens, CDC issued guidelines in

MMWR  /  October 7, 2011  /  Vol. 60

65

Supplement

November 1982 that were based on those previously recommended to protect against hepatitis B virus infection (25).
In March 1983, CDC, in conjunction with the Food and
Drug Administration and the National Institutes of Health
(NIH), issued interagency recommendations for the prevention
of AIDS on the basis of the epidemiologic data (Table) (26).
These recommendations, which were immediately endorsed by
a variety of professional and community organizations, were
developed before the cause of the syndrome was discovered and
2 years before antibody testing would be available for diagnostic
testing of individuals or screening of blood donations. Yet,
even in retrospect, the recommendations appear to have been
essentially correct. They illustrate the power of epidemiologic
investigation in understanding and preventing new diseases,
even in the absence of an identified cause.
The causative retrovirus was described by Drs. Francois
Barre-Sinoussi and Luc Montagnier and their colleagues from
the French Pasteur Institute in May 1983 (27). Additional
proof of causality, as well as the demonstration of sustained
viral growth in vitro, was reported by Dr. Robert Gallo and
colleagues at the U.S. National Cancer Institute, NIH, in
1984 (28). In 2008, Drs. Barre-Sinoussi and Montagnier were
awarded the Nobel Prize in medicine for their discovery of
human immunodeficiency virus (HIV).
The availability of laboratory reagents and techniques to
identify HIV led to rapid scientific advances in understanding the natural history of the infection and AIDS. CDC’s
Dr. Paul Feorino and colleagues first demonstrated persistent
HIV infection among seropositive blood donors who had
transmitted HIV many years earlier, indicating that HIVinfected persons can be asymptomatic and viremic for many
years and that seropositivity is equivalent to infection and
infectivity (29). Dr. Harold Jaffe and colleagues from the San
Francisco Health Department and CDC’s Hepatitis Division
reported a 6-year follow-up of a cohort of gay men originally
recruited in 1978 for studies of hepatitis B virus infection in
San Francisco (Figure 2) (30). By analyzing retrospectively
obtained specimens, they found that at the time the first few
AIDS cases were reported from the cohort in 1981, 30% of
the 7,000 men were already infected with HIV. If these data
were extrapolated nationally, as many as 200,000–300,000
gay men had already been infected in the United States at the
time of the 1981 case reports. Using these natural history data,
Dr. Meade Morgan projected that the cumulative incidence of
AIDS would reach 270,000 by 1991 (31). These projections
provided a wake-up call to those concerned about the future
economic and human costs of the epidemic in this country.
By the mid-1980s, substantial concern existed about transmission of HIV through casual contact or by arthropods.
Dr. Gerald Friedland and colleagues showed no evidence
66

MMWR  /  October 7, 2011  /  Vol. 60

TABLE. Recommendations for prevention of acquired immune deficiency syndrome (AIDS), March 1983
1. Sexual contact should be avoided with persons known or suspected to
have AIDS. Members of high risk groups should be aware that multiple
sexual partners increase the probability of developing AIDS.
2. As a temporary measure, members of groups at increased risk for AIDS
should refrain from donating plasma and/or blood. This recommendation includes all individuals belonging to such groups, even though
many individuals are at little risk of AIDS. Centers collecting plasma and/
or blood should inform potential donors of this recommendation. The
Food and Drug Administration (FDA) is preparing new recommendations for manufacturers of plasma derivatives and for establishments
collecting plasma or blood. This is an interim measure to protect
recipients of blood products and blood until specific laboratory tests
are available.
3. Studies should be conducted to evaluate screening procedures for their
effectiveness in identifying and excluding plasma and blood with a high
probability of transmitting AIDS. These procedures should include
specific laboratory tests as well as careful histories and physical
examinations.
4. Physicians should adhere strictly to medical indications for transfusions,
and autologous blood transfusions are encouraged.
5. Work should continue toward development of safer blood products for
use by hemophilia patients.
Source: CDC. Prevention of acquired immune deficiency syndrome (AIDS): report
of inter-agency recommendations. MMWR 1983;32:101–3.

of transmission among close household contacts of HIVinfected patients in New York City (32). In a cover story for
LIFE magazine, physicians from Florida had postulated that
the high prevalence of AIDS in Belle Glade, a small town in
southern Florida, resulted from insect transmission of HIV.
Dr. Kenneth Castro and his colleagues published an extensive
epidemiologic investigation in that community that did not
support that hypothesis (33).
Drs. Steven McDougal and Linda Martin from CDC demonstrated that heat would inactivate HIV, providing a basis
for production of clotting factor concentrate that would no
longer transmit HIV infection (34). CDC laboratories also
validated HIV antibody tests and provided proficiency testing
materials for state public health laboratories and others. In
the early HIV era, recommendations for HIV counseling and
testing (35) and prevention of perinatal transmission (36) were
made, and CDC provided resources and training for alternate
testing and counseling sites (sites other than blood collection
centers) (37). During the first 8 years of the epidemic, nearly
50 sets of recommendations and guidelines for AIDS were
published in MMWR.

The Global Epidemic
By 1984, case reports described AIDS in Zaire (now the
Democratic Republic of Congo), and a team of investigators
including Dr. Joseph McCormick and Ms. Sheila Mitchell
from CDC; Dr. Thomas Quinn from the National Institute
of Allergy and Infectious Diseases, NIH; and Dr. Peter Piot

Supplement

FIGURE 2. Percent of men with human T-lymphotropic virus, type III/
lymphadenopathy-associated virus antibody (seropositive) and
number with acquired immunodeficiency syndrome (AIDS), by year
of diagnosis, San Francisco City Clinic Cohort, 1978–1984

Source: Jaffe HW, Darrow WW, Echenberg DF, et al. The acquired immune deficiency syndrome in a context of homosexual men. A six-year follow-up study.
Ann Intern Med 1985;103:210–4. Reprinted with permission.

from the Institute of Tropical Medicine in Belgium, made a
joint visit to Kinshasa to verify the initial reports. Dr. Jonathan
Mann was then recruited by CDC to establish a long-term
project in Zaire, Project SIDA, in partnership with Dr. Bila
Kapita from Mama Yemo Hospital in Kinshasa and colleagues
from NIH and the Institute of Tropical Medicine. Projet SIDA
would rapidly become the largest HIV/AIDS research project
on the continent during the 1980s.
In 1985, CDC inaugurated and hosted in Atlanta the First
International Conference on AIDS. The conference, chaired by
Dr. Gary Noble of CDC, was attended by >2,000 registrants.
At the conference, Dr. Mann delivered the first presentation
about AIDS in Africa at a U.S. meeting and reported that the
incidence of AIDS in Kinshasa was 15–30 times higher than
in the United States (38).
Dr. Mann left Zaire to begin the Global Programme on AIDS
at the World Health Organization. He was replaced as Project
SIDA Director by Dr. Robert Ryder in 1986 and then by Dr.
William Heyward in 1989. Dr. Kevin De Cock was the first
Director of Projet Retro CI, CDC’s second African research site,
in Abidjan, C’ote D’Ivoire. Shortly thereafter, Dr. Bruce Weniger
initiated CDC’s HIV research site in Bangkok, Thailand.
Since the early days, CDC’s response to the global HIV pandemic has been extensive. In the early 1980s, staff were detailed
to, or volunteered from, many different parts of the agency.
Initial CDC funding supported state and local health departments for surveillance and prevention activities, including HIV
counseling and testing. In addition to these traditional CDC

partners, hundreds of local and national community-based
organizations were enlisted in the prevention efforts, and CDC
provided support for school-based HIV education initiatives.
At CDC headquarters, the AIDS epidemic highlighted
the need for behavioral and social scientists to participate
in public health research.. Before 1981, only a handful of
doctoral-trained behavioral and social scientists were on staff
in Atlanta, but the numbers quickly grew. CDC’s reputation
and staff accomplishments also led to formation of the Global
AIDS Program. Overall, many thousands of CDC staff have
worked—and continue to work—with tens of thousands of
colleagues throughout the world in the fight against AIDS.
Well over 400 reports on HIV/AIDS have been published
in MMWR since that first report in June 1981. The ongoing
impact of CDC’s scientific and programmatic contributions
remains outstanding.

Lessons for the Future
In three decades, AIDS has emerged has a major global health
problem. As the world faces the long struggle to combat the
epidemic, several lessons from the early days emerge.
First, excellent surveillance of the initial AIDS cases was critical in responding to the epidemic. Surveillance was first needed
to track the epidemic and direct etiologic investigations but
later became critical in formulating early prevention and safety
recommendations before HIV was discovered. Surveillance
remains equally important now throughout the world to target
resources and evaluate prevention efforts.
Second, the rapid identification of HIV as the causal agent
of AIDS led to a much better understanding of transmission,
natural history, and spectrum of illness. This understanding
allowed for more targeted prevention efforts and paved the way
for development of the first effective treatments.
Third, innovative science has in many ways exceeded the
expectations of skeptics. These innovations include improvements in HIV diagnostics, such as rapid antibody testing and
viral load assays; identification of zidovudine (AZT), the first
antiretroviral (ARV) drug; use of ARVs to reduce perinatal
transmission; effectiveness of prevention in many communities through counseling and testing, as well as behavior-based
methods; and development of effective biomedical interventions, such as male circumcision, preexposure prophylaxis, and
vaginal microbicides in addition to condom use and needle
and syringe exchange. Finally, development of the three-drug
ARV regimen (highly active antiroviral therapy [HAART])
has saved the lives of millions of persons with HIV infection
in both the developed and developing worlds.

MMWR  /  October 7, 2011  /  Vol. 60

67

Supplement

Fourth, as with most health problems where the etiology
is well understood, prevention deserves primacy. Several million persons become newly infected with HIV each year, yet
only approximately five to six million persons worldwide have
been treated with HAART. The goal of universal HIV treatment cannot be met unless HIV incidence can be reduced.
Furthermore, as long as the majority (or a substantial minority)
of HIV-infected persons are unaware of their infection status,
prevention and treatment efforts will be hampered.
Finally, committed persons have made—and will continue
to make—the difference. Persons with HIV infection have
played crucial roles in communities throughout the world by
giving voice to their concerns and courageously advocating for
HIV. Scientists in many disciplines who continue to discover
breakthroughs for prevention and care provide hope for the
future. Clinicians and caregivers and public health practitioners
will pursue their work with an expanded science base.
The future of prevention and care for HIV means standing
up to two societal foes, scarcity and discrimination, as much
as the biologic challenge of the virus itself. Global resources
for prevention and care for HIV remain severely short of the
needs. Successful efforts for prevention must also include
sustained and visible efforts to combat stigma and prevent
discrimination.
This last lesson was emphasized by the late Jonathan Mann,
who perished with his wife, HIV vaccine researcher, Mary
Lou Clements-Mann, in a 1998 plane crash. Dr. Mann was
the person most responsible for first calling world attention
to AIDS and linking it to concerns about human rights. In
one of his last public addresses, on the occasion of the 50th
anniversary of the Universal Declaration of Human Rights, he
stated, “Our responsibility is historic. For when the history of
AIDS and the global response is written, our most precious
contribution may well be that, at a time of plague, we did not
flee, we did not hide, we did not separate ourselves” (39). The
hope for the tens of millions affected by HIV currently and
in the future will depend upon scientists, practitioners, and
citizens working together.
References
1. CDC. Pneumocystis pneumonia—Los Angeles. MMWR 1981;30:1–3.
2. Hymes, KB, Greene JB, Marcus A, et al. Kaposi’s sarcoma in homosexual
men: a report of eight cases. Lancet 1981;318:598–600.
3. Walzer PD, Perl DP, Krogstad DJ, Rawson PG, Schultz MG. Pneumocystis
carinii pneumonia in the United States: epidemiologic, diagnostic, and
clinical features. Ann Intern Med 1974;80:83–93.
4. CDC. Kaposi’s sarcoma and Pneumocystis pneumonia among homosexual
men—New York City and California. MMWR 1981;30:305–8.
5. CDC. Revision of the case definition of acquired immunodeficiency
syndrome for national reporting—United States. MMWR 1985;34:373–5.
6. CDC. Revision of the CDC case definition for acquired immunodeficiency
syndrome. MMWR 1987;36(Suppl):82–94.

68

MMWR  /  October 7, 2011  /  Vol. 60

7. CDC. Impact of the expanded AIDS surveillance case definition on
AIDS case reporting—United States, first quarter, 1993. MMWR
1993;42:308–10.
8. CDC. Task Force on Kaposi’s Sarcoma and Opportunistic Infections.
Epidemiologic aspects of the current outbreak of Kaposi’s sarcoma and
opportunistic infections. N Engl J Med 1982;306:248–52.
9. CDC. Persistent generalized lymphadenopathy among homosexual
males. MMWR 1982;31:249–51.
10. Jaffe HW, Choi K, Thomas PA, et al. National case control study of
Kaposi’s sarcoma and Pneumocystis carinii pneumonia in homosexual
men: epidemiologic results. Ann Intern Med 1983;99:145–51.
11. Rogers MF, Morens DM, Stewart JA, et al. National case-control study
of Kaposi’s sarcoma and Pneumocystis carinii pneumonia in homosexual
men: Part 2. Laboratory results. Ann Intern Med 1983;99:151–8.
12. CDC. A cluster of Kaposi’s sarcoma and Pneumocystis carinii pneumonia
among homosexual male residents of Los Angeles and Orange counties,
California. MMWR 1982;31:305–7.
13. Auerbach DM, Darrow WW, Jaffe HW, Curran JW. A cluster of cases
of the acquired immune deficiency syndrome: patients linked by sexual
contact. Am J Med 1984;76:487–92.
14. CDC. Pnemocystis carini pneumonia among persons with hemophilia
A. MMWR 1982;31:365–7.
15. CDC. Unexplained immunodeficiency and opportunistic infections in
infants—New York, New Jersey, California. MMWR 1982;31:665–7.
16. Oleske J, Minnefor A, Cooper R, et al. Immune deficiency syndrome
in children. JAMA 1983;249:2345–9.
17. Rubenstein A, Sicklick M, Gupta A, et al. Acquired immunodeficiency
with reversed T4/T8 ratios in infants born to promiscuous and drugaddicted mothers. JAMA 1983;249:2350–6.
18. CDC. Immunodeficiency among female sexual partners of males with
acquired immune deficiency syndrome (AIDS). MMWR 1983;​31:697–8.
19. Harris C, Small CB, Klein RS, et al, Immunodeficiency in female sexual
partners of men with the acquired immunodeficiency syndrome. N Engl
J Med 1983;308:1181–4.
20. CDC. Possible transfusion-associated acquired immune deficiency
syndrome (AIDS)—California. MMWR 1982;31:652–4.
21. Curran JW, Lawrence DL, Jaffe HW, et al. Acquired immunodeficiency
syndrome (AIDS) associated with transfusions. N Engl J Med 1984;​
310:69–75.
22. CDC. Opportunistic infections and Kaposi’s sarcoma among Haitians
in the United States. MMWR 1982;31:353–61.
23. Liautaud B, Laroche C, Duvivier J, et al. Le sarcoma de Kapsoi (maladie
de Kaposi) est-il-frequent en Haiti? Presented at the 18th Congres des
Medecins francophones de l’hemisphere Americain: Port-Au-Prince,
Haita, April 1982.
24. Farmer P. AIDS and accusation: Haiti and the geography of blame,
Berkeley, CA: University of California Press; 1992.
25. CDC. Acquired immune deficiency syndrome (AIDS): precautions for
clinical and laboratory staffs. MMWR 1982;31:577–80.
26. CDC. Prevention of acquired immune deficiency syndrome (AIDS):
report of inter-agency recommendations. MMWR 1983;32:101–3.
27. Barre-Sinoussi F, Chermann JC, Rey F, et al. Isolation of a T-lymphotropic
retrovirus from a patient at risk for acquired immune deficiency
syndrome (AIDS). Science 1983;220:868–71.
28. Gallo RC, Salahuddin SZ, Popovic M, et al. Frequent detection and
isolation of cytopathic retroviruses (HTLV-III) from patients with AIDS
and at risk for AIDS. Science 1984;224:500–3.
29. Feorino PM, Jaffe HW, Palmer E, et al. Transfusion-associated acquired
immunodeficiency syndrome (AIDS): evidence for persistent infection
in blood donors. N Engl J Med 1985;312:1293–6.
30. Jaffe HW, Darrow WW, Echenberg DF, et al. AIDS, AIDS-related
conditions, and exposure to HTLV- III/LAV in a cohort of homosexual
men: a 6-year follow-up study. Ann Intern Med 1985;103:210–4.
31. Morgan WM, Curran JW. Acquired immunodeficiency syndrome (AIDS):
current and future trends. Public Health Rep 1986;101:459–65.

Supplement

32. Friedland GH, Saltzman BR, Rogers MF, et al. Lack of transmission of
HTLV-III/LAV infection to household contacts of patients with AIDS
or AIDS-related complex with oral candidiasis. N Engl J Med
1986;314:344–50.
33. Castro KG, Lieb S, Jaffe HW, et al. Transmission of HIV in Belle Glade,
Florida: lessons for other communities in the United States. Science
1988;239:193–8.
34. McDougal JS, Martin LS, Cort SP, Mozen CM, Heidebrant CM, Evatt
BL. Thermal inactivation of the acquired immunodeficiency syndrome
virus, human T-lymphotropic virus–III/lymphaderopathy-associated
virus, with special reference to antihemophilic factor. J Clin Invest
1985;76:875–7.
35. CDC. Public Health Service guidelines for counseling and antibody testing
to prevent HIV infection and AIDS. MMWR 1987;36:509–15.

36. CDC. Recommendations for assisting in the prevention of perinatal
transmission of human T-lymphotropic virus type III/lymphadenopathyassociated virus and acquired immunodeficiency syndrome. MMWR
1985;34:721–6.
37. CDC. Human T-lymphotropic virus type III/lymphadenopathy associated
virus antibody testing at alternate sites. MMWR 1986;35:284–7.
38. Mann JM, Francis H, Asila PK, et al. Surveillance for acquired
immunodeficiency syndrome in a central African city: Kinshasa, Zaire.
JAMA 1986;255:3255–9.
39. Mann JM. Presentation at XII International Conference on AIDS, June
28–July 3, 1998, Geneva, Switzerland.

MMWR  /  October 7, 2011  /  Vol. 60

69

Supplement

Fifty Years of Progress in Chronic Disease Epidemiology and Control
Patrick L. Remington MD1
Ross C. Brownson, PhD2,3
1Department of Population Health Sciences, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin.
2Prevention Research Center in St. Louis, George Warren Brown School of Social Work, Washington University in St. Louis, St. Louis, Missouri
3Department of Surgery and Alvin J. Siteman Cancer Center, Washington University School of Medicine, Washington University in St. Louis, St. Louis, Missouri
Corresponding author: Patrick L. Remington, MD, 4263 Health Science Learning Center, 750 Highland Avenue, Madison, WI 53705; Phone: 608-263-1745;
Fax: 608-262-2327; E-mail: [email protected].

Introduction
During the past century in the United States, advances in
public health and health care have increased life expectancy
by approximately 30 years and led to dramatic changes in the
leading causes of death (1). As chronic diseases became the
leading causes of illness and death in the United States by
the middle of the 20th century (2), public health researchers
began to shift their focus to identifying their complex and
interrelated causes. In addition, researchers began to study ways
to prevent and control chronic diseases through clinical and
community-based interventions. This increasing importance
and interest in chronic diseases led to the establishment of the
National Center for Chronic Disease Prevention and Health
Promotion at CDC in 1988 and is reflected in the publication
of articles about chronic diseases in MMWR, with few if any
articles before 1980, increasing to about 20% of articles since
1990 (Figure 1).
Considerable progress has been made during the past 50
years in understanding the causes of chronic diseases, as well
as in development of the evidence for effective strategies to
prevent, detect, or control chronic diseases (3). This report
focuses on progress in four areas by:
• Describing progress in understanding the causes of chronic
disease through epidemiologic research;
• Describing advances in understanding the evidence base
for prevention and control, through intervention research;
• Assessing the impact of these advances on the prevalence
of chronic diseases in the United States, as measured by
reductions in chronic disease morbidity and mortality;
and
• Discussing the lessons learned during the past 50 years in
translating this research into practice in the United States.
This report provides a synopsis of progress by using key
examples within the four areas rather than an exhaustive review
of chronic disease epidemiology and control during the past
half-century.

70

MMWR  /  October 7, 2011  /  Vol. 60

Progress in Understanding the
Causes of Chronic Diseases
By the 1960s, large-scale studies such as the Framingham
Heart Study, the Seven Countries Study, and the British
Doctors Study, began to identify the leading causes of chronic
diseases (4). These studies elucidated the contributions of cigarette smoking, diet, physical inactivity, and high blood pressure
to the leading causes of death. Over 50 years or more, these
and other studies have helped establish the behavioral causes
of many of the chronic diseases affecting humans. None of
these studies has established the causes of any chronic disease
by itself; rather, the causes have been established on the basis
of a large number of studies that used different designs and
were conducted in different populations (5).
The discovery that smoking caused lung cancer can be viewed
as the first and most important advance in chronic disease
etiology. The results from the first studies of lung cancer were
summarized in the first Surgeon General’s Report on Smoking
and Health, published in 1964. Establishment of the “criteria
for causality” in this report was critical in the evolution of the
understanding of the causes of chronic disease, given the long
latency between exposures and outcomes; the multiple causes
of chronic diseases; and the multiple consequences of many
of the risk factors. These criteria, subsequently called the “Hill
criteria,” would continue to be used over time to consider the
causal risk factors for other chronic diseases (6).
During and after the 1960s, researchers continued to study
the relationship between risk factors (e.g., poor diet, lack of
exercise, high blood pressure) and major chronic diseases. For
example, the “diet–heart” hypothesis was tested in observational
studies such as the Framingham Heart Study, a prospective
cohort study of residents of Framingham, Massachusetts (4).
At the same time, researchers shifted their focus from chronic
diseases to the behavioral risk factors preceding the diseases. In
1993, these studies were summarized in the seminal publication
“Actual Causes of Death in the United States” by McGinnis and
Foege (7). These researchers used the results from decades of

Supplement

FIGURE 1. Percentage of MMWR articles about chronic diseases,
conditions, or risk factors — United States, 1965–2010
30

Cause

No.

Tobacco
Poor diet and physical inactivity
Alcohol consumption
Microbial agents
Toxic agents
Motor vehicles
Firearms
Sexual behavior
Illicit drug use
Total

25

Percentage

TABLE 1. Actual causes of death — United States, 2000

20
15
10
5
0
1965 1970 1975 1980 1985 1990 1995 2000 2005 2010

Year

epidemiologic research to demonstrate that approximately half
of all deaths could be attributed to relatively few risk factors;
their work was updated later by Mokdad (8) (Table 1).
In 1974, the Canadian Lalonde Report (9) concluded that
the health of a population could be considered in four broad
elements: human biology, environment, lifestyle, and healthcare organization. This model of the “multiple determinants of
health” provides a broad conceptual framework for considering
the factors that influence health in a community (10). This
model takes a multidisciplinary approach, uniting biomedical
sciences, public health, psychology, statistics and epidemiology, economics, sociology, education, and other disciplines.
Social, environmental, economic, and genetic factors are seen
as contributing to differences in health status and, therefore,
as presenting opportunities to intervene.
Other research during this time focused on the role of
social and economic factors that increased risk for chronic
disease. One of the most important investigators in this field
is Sir Michael Marmot, whose studies of British civil servants
clearly illustrate these concepts (11). His and others’ research
have since demonstrated that health behaviors alone do not
explain the risk related to occupation, income, education,
and other social determinants of health (12). A new academic
field of social epidemiology developed during this same period
and became best known for identifying the social gradient in
health, in which health outcome effects exist not only at the
extremes of high and low levels of education and income but
also at most gradations in between (13,14).
Research has increasingly demonstrated the contributions
to health by factors beyond the physical environment, medical care, and health behaviors. These include socioeconomic
position, race/ethnicity, social networks and support, work
conditions, economic inequality, and social capital (15). These
contributors were summarized in the Institute of Medicine’s

435,000
400,000
85,000
75,000
55,000
43,000
29,000
20,000
17,000
1,158,000

(%*)
(18.1)
(16.6)
(3.5)
(3.1)
(2.3)
(1.8)
(1.2)
(0.8)
(0.7)
(48.2)

Source: Reference 8. Mokdad AH, Marks JS, Stroup DE, Gerberding JL. Actual
cases of death in the United States, 2000. JAMA 2004;291:1238–45.
* Percentages of all deaths.

Future of the Public’s Health in the 21st Century, which stated
that “the greatest advances in understanding the factors that
shape population health during the last 2 decades…has been
the identification of social and behavioral conditions that
influence morbidity, mortality, and functioning” (16).

Progress in Developing EvidenceBased Chronic Disease Prevention
and Control Programs and Policies
As information about the causes of chronic diseases accumulated during the 1960s and 1970s, research began to focus on
intervention studies. Systematic reviews have been conducted
to determine which interventions are effective in preventing
or controlling chronic diseases (17). Information about hundreds of evidence-based interventions is now available from a
variety of sources, including the Guide to Clinical Preventive
Services (18), The Guide to Community Preventive Services
(19), MMWR Recommendations and Reports, The National
Guideline Clearinghouse (20), and the Cochrane Reviews.
More recently, the emphasis has shifted from what constitutes
acceptable intervention evidence to what processes in public
health settings will enable more widespread use of evidencebased practices. Several leading discoveries that have reduced,
or have the potential to reduce, the impact of chronic diseases
are described below.

Clinical Preventive Services
Research demonstrated that certain clinical preventive services, including screening, counseling, and preventive medications, are effective in preventing or controlling the leading
chronic diseases. During the past 50 years, for example, research
has demonstrated effective ways to counsel smokers to quit;
screen for breast, colon, and cervical cancer; and detect and

MMWR  /  October 7, 2011  /  Vol. 60

71

Supplement

Media and Policy Advocacy
Media messaging and policy advocacy can be important
methods for preventing chronic diseases. For example, research
has demonstrated that media and policy advocacy are effective
low-cost strategies for reducing smoking rates in the population. Specifically, comprehensive programs that focus on policy
changes (e.g., advertising restrictions, policies regarding clean
indoor air) can effectively reduce smoking rates in populations
(21), and these policy changes can be supported by media
advocacy (22). Changes in the policy environment can increase
demand for effective clinical interventions (e.g., physician
advice to patients for smoking cessation, access to cessation
services) and smoking prevention programs in organizational
settings (e.g., curricula in schools that focus on effective prevention strategies).

Environmental Interventions
Research has demonstrated that environmental interventions
might be effective in promoting physical activity and healthy
eating (23,24). The built environment—the physical form of
communities—includes land-use patterns (how land is used),
large- and small-scale built and natural features (e.g., architectural details, quality of landscaping, access to grocery stores),
and the transportation system (facilities and services that link
one location to another). Together, these elements shape access
to opportunities for physical activity and healthy eating.

Progress in Reducing the Impact of
Chronic Diseases
Public health surveillance can be used to assess the effectiveness of the interventions described above on reducing the
health burden from chronic diseases. Trends in selected chronic
disease death rates and related risk factors are described below.

72

MMWR  /  October 7, 2011  /  Vol. 60

Trends in the Leading Causes of Death
Since 1960, death rates for chronic diseases have changed
dramatically, especially reductions in deaths caused by heart
disease and stroke (Figure 2). Heart disease death rates have
declined by almost two thirds during the past 50 years, and
stroke rates have declined by more than three quarters. If the
1960 death rates for heart disease and stroke had persisted,
almost 1.5 million more deaths from these causes would occur
each year today. These major declines have resulted largely from
declines in smoking and improvements in diet, detection and
treatment of high blood pressure and high blood cholesterol,
and medical care and treatment (25).
Overall death rates for cancer have changed relatively little
during the past 5 decades, declining only 8%. This translates
to 49,000 fewer deaths each year today than during the 1960s
(26). These trends vary by patient sex and type of cancer. For
example, death rates for stomach, colon, uterine, breast, and
prostate cancers have declined during the past few decades
(27). However, this progress has been counterbalanced by
a dramatic increase in the rate of lung cancer deaths during
the past 50 years. Lung cancer became the leading cause of
cancer death among men in the 1950s and among women in
the 1990s. Although lung cancer rates now have started to
decline, they remain substantially higher today than in the
1960s (Figures 3 and 4).
Death rates for several other chronic diseases (e.g., diabetes,
chronic lung disease, chronic kidney disease) have changed
little or even increased during the past 50 years. Although
FIGURE 2. Trends in age-adjusted death rates for the leadings chronic
diseases — United States, 1960–2007
600
Heart disease
Cancer
Stroke

500
400

Rate

treat high blood pressure and high blood cholesterol. The
evolution of this clinical research led to establishment of the
US Preventive Services Task Force in 1984 to rigorously and
impartially assess scientific evidence for the effectiveness of
these and other clinical interventions. Its recommendations
are considered the standard for clinical preventive services. The
premier publication of the Task Force, The Guide to Clinical
Preventive Services, provides information about preventive
services that should be incorporated routinely into primary
medical care, and for which populations (18).

300
200
100
0
1960 1965 1970 1975 1980 1985 1990 1995 2000 2005

Year
Source: National Center for Health Statistics. Health, United States, 2010.
Hyattsville, MD: US Department of Health and Human Services, CDC, National
Center for Health Statistics; 2011. Available at www.cdc.gov/nchs/data/hus/
hus10.pdf.

Supplement

Rate

FIGURE 3. Trends in age-adjusted cancer death rates* for males —
United States, 1930–2006†

Death rates for chronic lower respiratory diseases, such as
bronchitis and emphysema, have increased by approximately
50% during the past 30 years, from 12.5 deaths per 100,000
persons in 1980 to 42.2 per 100,000 in 2009. The increased
death rate during 1960--2007 has been responsible for an excess
of about 42,000 deaths each year (Table 2). Death rates have
continued to increase during the past 20 years in both sexes
and all racial/ethnic groups (29).

Trends in Risk Factors for Chronic Diseases

Source: US Mortality Data, 1960 to 2006, US Mortality Volumes, 1930 to 1959,
National Center for Health Statistics, Centers for Disease Control and Prevention,
2009.
* Per 100,000, age adjusted to the US standard population.
† Due to changes in International Classification of Diseases coding, numerator
information has changed over time. Rates for cancer of the liver, lung and
bronchus, and colon and rectum are affected by these coding changes.

Rate

FIGURE 4. Trends in age-adjusted cancer death rates* for females
— United States, 1930–2006†

Source: US Mortality Data, 1960 to 2006, US Mortality Volumes, 1930 to 1959,
National Center for Health Statistics, Centers for Disease Control and Prevention,
2009.
* Per 100,000, age adjusted to the US standard population. Rates are uterine
cervix and uterine corpus combined.
† Due to changes in International Classification of Diseases coding, numerator
information has changed over time. Rates for cancer of the lung and bronchus,
colon and rectum, and ovary are affected.

trends in diabetes-related deaths are difficult to assess because
diabetes often is listed as a contributing cause of death, the
prevalence rates of diagnosed and undiagnosed diabetes have
increased steadily since the first National Health and Nutrition
Examination Survey during 1960–1962 (28). This increase
has been seen in all age groups, both sexes, and all racial/
ethnic groups and across the United States. The substantial
increase in obesity since the 1980s and the increased survival
rates among persons with the disease have contributed to the
increase in diabetes.

One of the most important successes since 1960 has been the
slow but substantial reduction in smoking rates in the general
population (Figure 5). The annual per capita consumption of
cigarettes peaked in 1963, and except for an increase during
1971–1973, consumption has steadily declined since then.
Smoking rates in the general population declined from about
four of every 10 adults during the early 1960s (51.2% for men
and 33.7% for women) to about two of every 10 adults today
(22.0% for men and 17.5% for women) with greater declines
for men than women (Figure 4) (30). Rates for teens remained
relatively stable from 1975 to the mid-1990s but have declined
steadily during the past decade (30,31).
In contrast, the rates of obesity for adults and children
have more than doubled since the 1960s (Figure 5) (30,32).
Prevalence rates of obesity (body mass index >30) among adults
increased from <15% during the 1960s to >35% today, with
most of that increase occurring since the 1980s (30). Although
the magnitude of increase varies, the increase is observed in all
age groups, both sexes, all racial/ethnic groups, and all states
(30,32).
The causes of this obesity epidemic are complex. Since the
National Health and Nutrition Examination Survey was first
administered in 1971, many changes have occurred in food
consumption. The quantity of food and beverages consumed,
the fraction of meals eaten outside the home, portion sizes,
and energy density have increased substantially (33). Although
diets have decreased in saturated fats and cholesterol, including less red meat and more chicken, total calories consumed
might have increased. In addition, evidence suggests that rates
of physical activity have decreased over time (34). As expected,
rates of diabetes and other obesity-related chronic diseases have
increased during this time.
The rates of alcohol use, as measured by apparent per capita
alcohol sales (gallons of ethanol) increased during the past 50
years, from 2.1 gallons per person aged >15 years in 1960 to 2.3
in 2007, after peaking at 2.8 in 1981 (35). However, long-term
trends in the prevalence of alcohol abuse and dependence in
the United States are difficult to assess. Population-based studies conducted during 1991–2002 showed that the prevalence

MMWR  /  October 7, 2011  /  Vol. 60

73

Supplement

TABLE 2. Trends in the leading causes of chronic disease–related deaths — United States, 1960 and 2009
Rate,* by year

Trends, 2009 vs. 1960

Disease†

1960

2009

Heart disease
Cancer
Stroke
Diabetes
Liver disease
Pneumonia & influenza
Accidents
Suicide
Homicide
Total

559
194
178
22.5
13.3
53.7
62.3
12.5
5.0

180
174
38.9
20.9
9.2
16.2
37
11.7
5.5

% Change
–68%
–10%
–78%
–7%
–31%
–70%
–41%
–6%
+10%

Rate difference*
–379
–20
–139
–1.6
–4.1
–38
–25
–0.8
+0.5

No. lives saved (lost)§
1,137,000
60,000
417,300
4,800
12,300
112,500
75,900
2,400
(1,500)
820,700

Sources: Health, United States, 2010: with special feature on death and dying. Hyattsville, MD: US Department of Health and Human Services, CDC, National Center
for Health Statistics; 2011. Available at www.cdc.gov/nchs/data/hus/hus10.pdf; and Kochanek KD, Xu JQ, Murphy SL, et al. Deaths: preliminary data for 2009. National
Vital Statistics Reports 2011;59(4). Available at http://www.cdc.gov/nchs/data/nvsr/nvsr59/nvsr59_04.pdf.
* Per 100,000 population (age adjusted to the 2000 US population).
† For chronic obstructive pulmonary disease, comparison is 1980 vs. 2009, as follows: 1980 rate—28.3; 2009 rate—42.2; % change, 2009 vs. 1980—+49%; rate difference—+14; no. lives saved: 41,700.
§ Estimated by multiplying the rate difference by the 2010 US population (300 million persons) rounded to the nearest 1,000.

of alcohol dependence decreased significantly (from 4.4% to
3.8%), whereas the prevalence of alcohol abuse increased significantly (from 3.0% to 4.6%) (36). This increase occurred
among both sexes and was especially marked among young
black, Hispanic, and Asian women.

National Outreach and Education
Programs

Percentage

Despite advances in chronic disease epidemiology and
control, a long latency period exists between scientific understanding of a viable chronic disease control method and its
widespread application on a population basis. One of the first
nationwide programs that successfully accelerated translation of
Looking Back: Lessons Learned
evidenced-based interventions into practice was the National
during the Past 50 Years of Chronic
High Blood Pressure Education Program. It was established by
the U.S. Congress in 1972 to promote nationwide detection,
Disease Epidemiology and Control
treatment, and control of hypertension through education
Considerable progress has been made during the past 50 years
programs and referrals. The program used a consensus-building
in understanding the causes of chronic diseases. The successes
approach to develop strategies to address hypertension through
and failures of efforts to translate this research into practice
a broad-based partnership among federal agencies, national
have taught some important lessons.
voluntary organizations, state health departments, and community-based programs.
FIGURE 5. Trends in the prevalence of smoking and obesity — United States,
1960–2010
Similar programs were used to accelerate
dissemination of cholesterol screening and
45
treatment and, more recently, a large-scale
40
Obesity
Smoking
program to promote early detection of breast
35
and cervical cancers. This CDC-supported
30
initiative is the National Breast and Cervical
25
Cancer Early Detection Program, which
20
provides screening for breast and cervical
15
cancers to low-income, uninsured, and
10
underserved women in all 50 states, the
5
District of Columbia, five U.S. territories,
0
and 12 American Indian/Alaska Native tribes
1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010
or tribal organizations (37).
Year
Source: Obesity data: National Center for Health Statistics. Health, United States, 2010. Hyattsville, MD:
US Department of Health and Human Services, CDC, National Center for Health Statistics; 2011. Available
at www.cdc.gov/nchs/data/hus/hus10.pdf. Smoking data: CDC. Current cigarette smoking among adults
aged ≥18 years—United States, 2005–2010. MMWR 2011;60:1207–1212..

74

MMWR  /  October 7, 2011  /  Vol. 60

Supplement

Successful chronic disease prevention and control interventions generally have used comprehensive approaches that have
focused on environmental and policy changes. Success in
reducing health risk behaviors in the population has resulted
largely from comprehensive integration of numerous environmental and policy approaches that have complemented
individual behavior and lifestyle modification strategies (38).
For example, progress in reducing smoking rates has been
greatest when state-based programs have used a comprehensive
strategy including such interventions as tax increases, policies
regarding clean indoor air, youth access limitations, media
advocacy, and counteradvertising (39). A comprehensive
strategy can benefit all persons exposed to the environment,
in contrast to a strategy that focuses on changing the behavior
of one person at a time. In nearly all cases, these interventions
have required new skills and nontraditional partnerships with
individuals and organizations not working directly in public
health. For example, to address the major physical barriers to
an active lifestyle in U.S. cities, urban planners, transportation experts, and persons working in parks and recreation are
essential to developing an environment and political will that
can promote physical activity.

Unintended Consequences of
Interventions
One unintended consequence of many public health interventions to prevent or control chronic diseases is the development of health disparities among poor and less educated
persons and minorities. Despite major progress in reducing
chronic diseases and their risk factors during the past 50 years,
health disparities have persisted and, in some cases, have arisen
where none existed before. The most obvious example involves
the trends in smoking since 1965. At that time, smoking rates
were unrelated to the level of education, but today level of
education is a major predictor for smoking (Figure 6). These
differences in smoking rates will lead to subsequent disparities
in smoking-related chronic diseases (40).
Disparities tend to develop as an unintended consequence
when programs or policies are most effective for persons with
higher levels of education (e.g., information campaigns), higher
incomes (e.g., promoting healthier but more expensive foods);
or health insurance (e.g., promoting the use of clinical preventive services, such as colonoscopy). Relatively few programs
have been developed to specifically reduce health disparities
by focusing on populations in greatest need.

FIGURE 6. Trends in the prevalence of smoking, by education level
— United States, 1966–2005
50

3 decades of widespread
use led to dramatic lowering of acceptable occupational

Supplement

TABLE 3. New and reemerging epidemic diseases broadly related to environmental factors reported in MMWR — 1961–2010
Disease/syndrome

Date of initial report, location

Hepatic angiosarcoma

2/15/1974, KY

Toxic oil syndrome

5/25/1981, Spain

Eosinophilia-myalgia syndrome

11/17/1989, NM

Toxic hypoglycemic syndrome
(Jamaican vomiting sickness)
Epidemic neuropathy*

1/31/1992, Jamaica

Renal failure†

8/2/1996, Haiti;
12/11/2009, Nigeria
12/9/1994, OH

Acute idiopathic pulmonary
hemorrhage among infants
Acute aflatoxicosis§
Gulf War illness

3/18/1994, Cuba

9/3/2004, Kenya
6/16/1995, Veterans

Presentation
Cluster of fatal liver cancer cases in vinyl chloride
polymerization workers
Atypical pneumonia, eosinophilia, and
neuromuscular disease from illicit cooking oil
Eosinophilia, neuromuscular disease from
L-tryptophan dietary supplement
Profound hypoglycemia, vomiting, convulsions
from ingestion of unripe ackee fruit
Subacute optic and peripheral neuropathy likely
from nutritional deficiency/tobacco smoking
Among children, from ingestion of diethylene
glycol–contaminated acetaminophen syrup
Hypothesized/unproven association with water
damage, mold, or fungi
Jaundice from moldy, contaminated maize
Unexplained illness/syndrome among Persian
Gulf War veterans

Date of follow-up reports
6/21/1974; 7/25/1975; 3/5/1976; 2/7/1997
9/4/1981; 5/5/1982
11/24/1989;12/8/1989; 1/12/1990;
2/16/1990; 5/18/1990; 8/31/1990 (×2);
11/2/1990; 8/21/1991

2/3/1995; 1/17/1997;3/10/2000;
6/15/2001; 9/10/2004

* CDC. Epidemic neuropathy—Cuba, 1991–1994. MMWR 1994;43:189–92.
† CDC. Fatalities associated with ingestion of diethylene glycol-contaminated glycerin used to manufacture acetaminophen syrup—Haiti, November 1995–June 1996.
MMWR 1996;45:649–50; and CDC. Fatal poisoning among young children from diethylene glycol-contaminated acetaminophen—Nigeria, 2008–2009. MMWR
2009;58:1345–7.
§ CDC. Outbreak of aflatoxin poisoning—eastern and central provinces, Kenya, January–July 2004. MMWR 2004;53:790–3.

exposures and to greatly increased protection of the general
population potentially exposed to vinyl chloride in different ways. The follow-up articles examined geographic
clusters of these cases in Connecticut and Wisconsin and
congenital malformations in two communities near production facilities; those reports did not link community
environmental exposures to these findings. In 1997, as
part of the celebration of CDC’s 50th anniversary,
MMWR reprinted the original 1974 report and a new
editorial note (9).
• Toxic oil syndrome. The initial MMWR article, published
in 1981, described approximately 1,300 persons in Spain
hospitalized for atypical pneumonia of uncertain etiology
(10). The second report, also published in 1981, documented that approximately 12,000 persons were hospitalized and included results of a case-control study that
determined the epidemic’s causative vehicle, illicit cooking
oil sold by itinerant peddlers in unmarked bottles (11).
The final article, which was published in 1982, one year
after the start of the epidemic, characterized the decrease
in new cases after protective actions and described the
evolution of the disease into a chronic phase with pronounced neuromuscular and other findings (12). Although
approximately 25,000 persons experienced this new disease, the specific etiologic agent was never identified
(13,14).
• Eosinophilia-myalgia syndrome. The initial MMWR
article, published in 1989, described three index patients
in New Mexico with eosinophilia-myalgia syndrome

(EMS) who had used L-tryptophan dietary supplements,
and a preliminary report of additional cases in the state
also was linked to ingestion of L-tryptophan (15). By the
following week, MMWR was able to report results from
four states that included two case-control studies linking
illness with specific lots of L-tryptophan (16). Subsequent
reports provided updates from national surveillance, added
to knowledge about the clinical spectrum, and provided
interim findings on potential contaminants in the
L-tryptophan (17). With nine updates in <1 year, MMWR
provided timely reporting of this rapidly developing epidemic. From the first report, MMWR also noted the
clinical similarity of EMS to toxic oil syndrome.

Asthma (26 Reports)
All MMWR articles related to asthma appeared after 1989,
and the majority related to asthma surveillance. MMWR
articles have covered such topics as asthma deaths and hospitalization among adults and children and self-reported illness
through the Behavioral Risk Factor Surveillance System (18).
Selected reports have evaluated health-care use (e.g., use of
inhaled medication and state and local programs). Asthma
triggered by specific chemicals and events are covered elsewhere
in this report.

Environmental Tobacco/Secondhand Smoke
(21 Reports)
Almost all MMWR articles on environmental or secondhand
tobacco smoke have appeared since 2000. Articles have covered

MMWR  /  October 7, 2011  /  Vol. 60

89

Supplement

such topics as biomonitoring data from the National Health
and Nutrition Examination Survey, which has tracked cotinine
levels among U.S. nonsmokers; levels have declined significantly during the past two decades—from a prevalence of 88%
≥0.05 ng/mL in the population aged ≥4 years (1988–1991)
to 40% in the population aged ≥3 years (2007–2008) (19).
Other MMWR articles have covered exposure to secondhand
smoke as reflected in data from the Behavioral Risk Factor
Surveillance System and other surveys.
A particular focus of MMWR has been the impact of state
and local policies to reduce smoking in indoor worksites and
in public places (e.g., the New York State comprehensive ban
for such sites); undoubtedly, successful implementation of these
policies has been a major reason for declining exposures. A recent
MMWR report took this one step further by noting reduced
hospitalization for myocardial infarction after implementation
of a smoke-free ordinance in the city of Pueblo, Colorado.

Environmental Threats and Risks
Specific Chemicals, Toxins, and Risk
Factors
Over the years, MMWR has published reports on the
adverse effects of a wide array of chemicals (metals, organic
compounds, and pesticides); dietary supplements; consumer
products; drugs, devices, and therapeutics; and substances of
abuse (Table 4 and 5). Most appear as single reports and covering them all here is not possible. Certain especially instructive
reports from each category are mentioned below.

Pesticides (28 reports)
Almost all the MMWR reports focused on acute toxicity
from inappropriate, unintended, or extremely high exposures.
Reported illnesses and deaths included those from fumigants
resulting from offsite drift from agricultural use of chloropicrin soil fumigant, phosphine release in a fumigated railroad
boxcar, home fumigation with sulfuryl fluoride, and soil fumigation with methyl bromide. MMWR reported a widespread
outbreak of food poisoning from aldicarb contamination of
melons that occurred in California in 1985 (20); subsequent
reports described poisoning from the illegal use of aldicarb as
a rodenticide and from its mistaken use in food preparation.
Illnesses and fatalities were reported from inappropriate use of
methyl parathion for insecticide control in a home environment with multiple possible routes of exposure to children;
a much earlier report from 1970 described poisoning among
teenaged boys harvesting tobacco. Two widespread outbreaks

90

MMWR  /  October 7, 2011  /  Vol. 60

of food contaminated with endrin were reported from Pakistan
(21) and the Middle East.

Metals (24 reports)
The vast majority of MMWR reports on metals were related
to mercury. The largest number addressed individual instances
of elemental mercury exposure in homes, schools, or neighborhoods. Multiple reports detailed exposure investigations with
potentially broad implications (e.g., identification of elevated
mercury exposure from use of interior latex paint that led to
changed regulations for such paints [22] and mercury poisoning among Hispanics in the Southwest from use of beauty
creams produced in Mexico [23]). Articles on the challenges
of addressing long-term exposure to low levels of toxins among
vulnerable populations appeared only rarely; one such report
contained a joint statement of the American Academy of
Pediatrics and the U.S. Public Health Service on exposure to
thimerosal in vaccines (24).

Organic compounds (25 reports)
The largest number of MMWR reports on organic compounds related to polychlorinated biphenyl (PCB) and dioxin
exposures. The PCB-related reports were primarily about
instances of high-level, acute exposures (e.g., from transformer
fires and food contamination episodes). The dioxin reports
focused on multiple prolonged inquiries into long-term effects
of dioxin exposure among Vietnam War veterans, Missouri residents exposed to dioxin in soil, and residents near the release of
dioxin by a chemical explosion in Seveso, Italy (25,26). Reports
on dioxin exposures represented the infrequent instances in
which MMWR published reports on the problem of long-term
consequences of chemical exposure.

Substances of abuse (40 reports)
Reports related to substances of abuse frequently have been featured in MMWR throughout the past five decades. The reports
often have related to specific episodes of apparently increased
rates of overdoses and fatalities; reports have documented
incidents where such increases were related to contaminants
(e.g., cocaine containing the antihelminthic drug levamisole
or heroin contaminated with scopolamine or clenbuterol). The
most dramatic example was the identification of Parkinsonism
after exposure to the street drug 1-methyl-4-phenyl-1,2,3,6tetrahydropyridine, a potent analogue of meperidine (27). As
noted elsewhere in this report, the reports from the Hazardous
Substances Emergency Events Surveillance (HSEES) system
on the acute public health consequences of methamphetamine
laboratories have had a strong public health impact (28).

Supplement

TABLE 4. Adverse effects of pesticides, metals, organics, and other exposures reported in MMWR — 1961–2011
Pesticides (no. reports)

Metals (no. reports)*

Methyl parathion (4)
Aldicarb (3)
Endrin (3)
Mosquito control spray (3)
Fumigants (3)
Diazinon (2)
Lindane (1)
Rodenticide containing TETS (1)
DEET (1)
Sulfuryl fluoride (1)
Chlorpyrifos (1)
Carbophenothion (Trithion) (1)
Organophosphates, multiple (4)

Mercury (21), including elemental
mercury, thimerosal, organic
mercury, and beauty cream
Thallium (2)
Arsenic (1)

Organic compounds (no. reports)

Other (no. reports)

Dioxin (8); including in Vietnam War veterans;
Missouri soil; and Seveso, Italy
Polychlorinated biphenyls (PCBs) (7)
Polybrominated biphenyls (PBBs) (2)
Dichlorodiphenyltrichloroethane (DDT) (2)
Trichloroethylene (TCE) (1)
Gasoline spill (1)
Biodiesel, home production (1)
Toluene diisocyanate (1)
Compounds at Love Canal, Niagara Falls, New York (1)
1, 3-dichloropropene (1)

Asbestos soil exposure (1)
Radiation (2)

*Not including lead poisoning and selected problems highlighted elsewhere in this report.

TABLE 5. Adverse effects of substances of abuse, dietary supplements, consumer products, drugs, devices, or therapeutics reported in MMWR
— 1961–2011
Substances of abuse
(no. reports)
Heroin (8)
Marijuana (6)
Cocaine (5)
Methamphetamine (5)
Gamma-Hydroxybutyric
acid (2)
Isobutyl nitrite (1)
Ecstasy (1)
General/multiple (12)

Dietary supplements and unorthodox
remedies (no. reports)

Consumer products (no. reports)

Asian traditional remedies (4), including
Chinese (3) and Hmong (1)
Herbal teas (3), including Kombucha, senna
cathartics (1), foxglove (1), and pyrrolizidine alkaloids (1)
Selenium (1)
High-dose vitamin A (1)
Turpentine/castor oil (1)
Chaparral (1)
Gamma-butyrolactone as source of
gamma-hydroxybutyrate (date-rape
drug) (1)
Kava (1)
Herbal supplement with aretemisinin (1)
Pennyroyal oil (1)
Raw carp gallbladders (1)
Mesotherapy (1)

Aerosolized carpet shampoo and aerosol
conditioner for shoes, boots, and leather
products (4)
Hexachlorophene baths and newborn
neuropathology (4)
Neonatal toxicity from use of phenolic laundry
detergents in neonatal nursery (3)
Pentachlorophenol exposure in log cabins (2)
Limes and phototoxic dermatitis (1)
Butyl caulk and toluene toxicity (1)
Naphthalene toxicity from mothballs (1)
Indoor paint containing Bis (tributyltin) oxide (1)
Chlorine gas generated by mixing bleach with
commercial phosphoric acid cleaner (1)
Household lamp oil ingestion and toxicity (1)
Spray adhesive use in pregnancy (1)
Digoxin-containing aphrodisiacs and death (1)

Silicone filler injections (1)

Drugs, devices, and therapeutics
(no. reports)
Nasopharyngeal radium irradiation/head
and neck cancer (1)
Benzyl alcohol preservatives/neonatal
deaths (1)
Diidohydroxyquin-induced blindness (1)
Prilocaine-induced
methemoglobinemia (1)
Ephedrine and cryoglobulinemia
vasculitis disease (1)
Cyanide tampering of Sudafed® (1)
Sporicidin device sterilant (1)
Undiluted 25% intravenous human
albumin and hemolysis (1)
Halofantrine and sudden death (1)
Colchicine overdose from pharmaceutical compounding error (1)
Gadolinium contrast agent and renal
disease (1)
Soluble barium sulfate contrast solution
and overdose deaths (1)

Dietary supplements (18 reports)

Consumer products (21 reports)

MMWR reports have appeared on lead poisoning from
Asian traditional home remedies (discussed previously under
childhood lead poisoning), arsenic poisoning from Hmong
traditional remedies, agranulocytosis from a phenylbutazonecontaining Chinese herbal remedy, and two reports of toxicity
from a traditional Chinese remedy called Jin Bu Huan. The
MMWR report on ingestion of raw carp gallbladders leading
to acute hepatitis and renal failure is one of the most unusual
food-related articles in this group.

The MMWR articles about consumer products constitute
another remarkable collection of acute toxicity and fatalities
related to unintended consequences from use of different
types of products (e.g., death from digoxin-containing aphrodisiacs [29]). One recurring theme was toxicity from aerosol
boot, shoe, and leather conditioner or sealants, with rapid
identification of cases leading to product recalls. Another
important theme was outbreaks of acute illness and death
in neonatal nurseries during the predisposable diaper period
(1960s–1970s): strong phenolic laundry detergents left residues
that were absorbed through the skin of vulnerable newborns,
leading to severe toxicity (30).

MMWR  /  October 7, 2011  /  Vol. 60

91

Supplement

Drugs, devices, and therapeutics (12 reports)
This group comprises dramatic reports of rarely experienced
toxicity and death from substances. It includes intentional
cyanide poisoning from deliberate tampering with over-thecounter medications (31), severe toxicity and deaths among
newborns exposed to benzyl alcohol preservatives in intravenous solutions, and severe barium toxicity from use of an
absorbable barium salt for radiologic examinations (32).

Environmental Media
Water (60 reports)
Approximately half of the MMWR reports on environmental media related to recreational water–associated illness
and its prevention. The strong environmental components in
these reports emphasized such concerns as swimming pool
and public spa inspections and guidelines (33) and injuries
and illness from incorrectly used pool chemical disinfectants
and chloramine vapors. Chemical contamination of drinking
water was reported 10 times, from chlordane, nitrates/nitrites,
sewage, phenol, caustic soda, and ethylene glycol; all of these
involved elevated exposures and sometimes illness as well (e.g.,
methemoglobinemia from nitrite exposure). Other environmental aspects included red tides, Pfiesteria spp., fluoridation,
outbreaks of disease related to Clostridium spp. and other
waterborne microbes, and one report on inadequately filtered
public drinking water. Only a few articles related to regulatory
standards for chemicals in drinking water.

Air (13 reports)
For a brief period after reauthorization of the Clean Air Act
in 1990 and the release of Healthy People 2000 (34), a flurry
of MMWR articles focused on the national impact of air pollution, particularly on the numbers of persons residing in
counties exceeding EPA air standards and on the air pollution
problems facing state and local health departments. MMWR
coverage on this topic slowed after 1995.

Food (46 reports)
Eleven reports on surveillance and FoodNet (available at
http://www.cdc.gov/foodnet/) focused primarily on trends
of outbreaks and illness related to specific microbial sources.
An article on safer and healthier foods, published as one of
MMWR’s series on achievements in public health throughout the 20th century, emphasized the role of environmental
advances (e.g., refrigeration and pasteurization). During

92

MMWR  /  October 7, 2011  /  Vol. 60

1960–1979, a total of 21 reports appeared on food poisoning
from metals (copper, cadmium, antimony, zinc, chromium,
and calcium), and seven more from nitrites, monosodium
glutamate, and fluoride, primarily related to contamination of
food from faulty equipment, incorrect preparation technique,
or mistaken ingredients. Six more recent reports described
unusual exposures (e.g., ammonia contamination of milk,
niacin intoxication from bagels, and nicotine poisoning from
ground beef ).

Hazardous wastes (14 reports)
During the early 1990s, soon after the creation and establishment of the Agency for Toxic Substances and Disease Registry,
MMWR published a short series of reports and alerts related to
developments at that agency (e.g., a statement on the agency’s
priority health conditions and research strategies) and a short
summary of the report on the public health implications of
medical waste.
During the past six years, six reports have summarized
findings from the Hazardous Substances Emergency Events
Surveillance (HSEES) system (e.g., on hazardous substances
released during rail transit in 18 states during a six-year period
[35]) and on hazardous chemical incidents in U.S. schools for
a six-year period. Certain of these HSEES reports on chemical releases and explosions in methamphetamine laboratories
helped policymakers more closely regulate these illicit production facilities (Table 6).

Environmental Places
Healthy homes, healthy communities, and global
environmental health (47 reports)
MMWR articles often include information about homes,
communities, and global health, usually in the context of a
specific problem (e.g., lead poisoning and asthma; hazardous
waste disposal; and earthquakes, drought, and famine). During
1961–2010, five reports were related to homeless persons,
usually in association with alcohol and substance abuse as risk
factors for death, and five reports focused on elevated radon
levels in homes. The built environment was a focus of nine
reports, most of which considered how environmental features
can promote physical activity among adults and children.
Environmental features of infectious diseases figured prominently in 17 reports related to outbreaks on cruise ships (e.g.,
one report documenting the preventive role of regular ship
inspections) and in 11 reports related to Legionnaires disease.

Supplement

Disasters

detailed volcano reports covered a wide array of actual and
potential health impacts (e.g., illness and death; respiratory
Natural disasters (153 reports)
health; safety for cleanup workers and loggers; impact on
water systems and other key infrastructure; testing for toxic
Before 1980, MMWR rarely reported on natural disasters;
chemicals in the ash; levels of ash fall and monitoring of
reports have escalated rapidly since then (Table 6). The increase
volcanic activity; and potential for long-term respiratory
undoubtedly reflects growing engagement by the public health
effects, including pneumoconiosis [37]).
community generally, and by CDC specifically, in disaster
•
Tornadoes. The group of nine MMWR articles on tornapreparedness and response. At CDC, this corresponds to the
does
began with a landmark report of a 1979 tornado
creation of the National Center for Environmental Health in
investigation in Wichita Falls, Texas; 44 persons were killed
1980 and its establishment of emergency response and disasand 171 were hospitalized for injuries (38). Guidance
ter epidemiology units, as well as to the more recent creation
regarding seeking shelter was reaffirmed; however, existing
of CDC’s Office of Terrorism Preparedness and Emergency
guidance on how to drive out of harm’s way was demonResponse (now the Office of Public Health Preparedness and
strated to be futile and led to updated recommendations.
Emergency Response). The increase in natural disaster reports
Subsequent reports highlighted the vulnerability of mobile
in MMWR has varied by the type of event: volcano reports
homes and the need for shelter areas in mobile home parks,
essentially focused on Mount St. Helens in 1980; tornado
the frequent inadequacy and failure of warning systems
reports peaked during the 1980s and 1990s; heat wave reports
and sirens, and guidance for adequate sheltering and
have been fairly level for the past three decades; and hurricaneprotection from injury and death. The last report specifirelated reports have increased steadily throughout the past
cally on tornadoes was published in 1997.
five decades. This section highlights the findings in six of the
•
Heat waves. The heat wave of summer 1980 led to descripmost numerous categories. Most of the reports related to U.S.
tive epidemiologic and case-control investigations in St.
disasters; however, the drought and famine category was global,
Louis and Kansas City, Missouri. A total of 784 deaths
and the earthquake category mostly so.
and severe illnesses were attributed to the heat. In another
• Volcanoes. Mount St. Helens came to life with a major
landmark study that changed longstanding public health
eruption on May 18, 1980 (36); MMWR published a
practice, the results demonstrated that even short periods
sequence of 14 reports to provide public health updates
in an air-conditioned environment were protective,
and recommendations. This series was a landmark in
whereas the then-common practice of distributing fans
MMWR’s initiating intense engagement on natural disasduring heat waves was counterproductive. Because the
ters; in addition to the MMWR sequence of reports, an
sweating mechanism is compromised during the early
MMWR report published on July 11, 1980, listed a series
stages of heat illness, delivery of hot air by fans exacerbates
of 33 technical information bulletins from the Federal
the situation (39). Reports of the Chicago heat wave in
Emergency Management Agency. The health bulletins
1995 and of the heat wave in Europe in 2003 emphasized
were all based on 23 Mount St. Helens volcano health
the vulnerability of older persons, infirm persons, and
reports from CDC that continued through February 1981
persons in socioeconomically deprived circumstances (40);
and were widely distributed throughout the Pacific
multiple reports affirmed the effectiveness of having relief
Northwest. Both MMWR short summaries and the more
workers mobilize older persons for trips
to air-conditioned environments (e.g.,
TABLE 6. Number of MMWR articles related to natural disasters, by decade — 1961–2010
shopping malls). Recent reports also have
Category
1961–1970 1971–1980 1981–1990 1991–2000 2001–2010
Total
highlighted other vulnerable groups for
Hurricanes
5
9
32
46
heat illness (e.g., farm workers and high
Heat waves
1
2
6
9
8
26
school athletes).
Extreme cold
4
7
7
18
Volcanoes
12
2
14
To provide timely public health guidEarthquakes
1
3
2
6
12
ance
before the winter and summer seaTornadoes
1
3
5
9
sons, MMWR has published approximately
Winter storms/snow
1
6
1
8
Floods
2
5
7
two dozen articles about hyperthermia
Drought/famine
5
1
1
7
and hypothermia, usually timed to appear
Lightning
1
1
2
before the winter or summer season
Wildfires
2
2
General
1
1
2
begins. These reports have provided sumTotal
1
16
32
45
59
153
mary statistics on heat- and cold-related
MMWR  /  October 7, 2011  /  Vol. 60

93

Supplement

deaths in the United States, instructive case reports from
multiple states highlighting risk factors, and updated
public health guidance.
• Earthquakes. Reports have focused on assessments of
mortality and morbidity (Italy, 1981; Loma Prieta,
California, 1989; Philippines, 1990); coccidioidomycosis
after the Northridge, California, earthquake in 1994;
health-related needs assessments linked to response or
surveillance (Turkey, 1999; Indonesia and Thailand tsunami, 2004), victim identification (Thailand tsunami,
2004), and surveillance (Haiti, 2010). These largely have
been acute-phase reports related to early assessments of
the magnitude of the problem and the extent of acute
public health needs.
• Hurricanes. Hurricanes have been increasingly the most
commonly reported category of natural disaster published
in MMWR, although approximately half of all such reports
(22/46) related to Hurricane Katrina. For the reports not
related to Hurricane Katrina or Hurricane Rita, four major
themes are apparent:
— Needs assessment surveys were reported in MMWR for
Hurricanes Ike, Wilma, a cluster of Florida hurricanes
in 2004 (three articles), Allison, Georges, Marilyn and
Opal, and Andrew (two articles). Needs assessments
usually targeted vulnerable groups (e.g., older persons
or rural populations).
— CO poisoning from unsafe generator use was reported
for Ike and the Florida cluster; also, one report involved dry
ice–induced CO poisoning in the 2004 Florida cluster.
— Medical examiner mortality data were analyzed and
reported in MMWR for the 2004 Florida cluster, Floyd,
Marilyn and Opal, Andrew, and Hugo (two articles).
— Surveillance data were reported for illness and injury
rates at Marilyn and Opal, Hugo, and Elena and
Gloria. The only other reports were related to mosquito-control efforts at Andrew and evaluation of
postdisaster work-related electrocutions from downed
power lines after Hugo.
Katrina was much more complex for multiple reasons,
including the devastating destruction and flooding over
multiple states, the approximately one million evacuees,
the long time frame for restoring basic functions and
repopulating New Orleans, and the extended periods spent
by thousands of persons in shelters and temporary trailers.
For Hurricane Katrina, four reports were published about
rapid needs assessment, three on CO poisoning, one on
mortality, and seven on surveillance for injury and illness
in health-care facilities and evacuation centers. Reports
related to the special features of Katrina included information about relief workers and occupational guidance, the
94

MMWR  /  October 7, 2011  /  Vol. 60

ubiquitous mold problem, a norovirus outbreak in a
shelter, two cases of toxigenic Vibrio chlolerae O1, and the
substantial number of tuberculosis patients temporarily
lost to follow-up during the chaos of the evacuation.
• Drought and famine. All seven reports describe investigations of major drought impact in Africa (Niger, 2005;
Ethiopia, 2000; Somalia, 1987; Niger 1985; Burkina Faso,
1985; Chad, 1985; and Mauritania, 1983). These reports
described collaboration among CDC, the U.S. Agency for
International Development, United Nations’ agencies
(e.g., UNICEF), and country governments. These reports
also described surveys that were conducted of children as
the most vulnerable group, and relief efforts focused on
nutritional status, respiratory and gastrointestinal disease,
measles vaccination, and vitamin A and C deficiencies.

Biologic, chemical, radiation, and nuclear
(four reports)
During 1961–2010, several additional reports were related
to potential adverse effects of chemical warfare agents. With
the growth of environmental programs at CDC—the National
Center for Environmental Health was created shortly after, and
largely as a result of, the 1979 Three Mile Island event—readers might anticipate more complete coverage of such events
in the future. Perhaps as a reflection of that, the most recent
MMWR covered in this report relates to radiologic and nuclear
preparedness and summarizes a CDC Grand Rounds session
(41); additional reports relate to potential adverse effects of
chemical warfare agents.

Terrorism
World Trade Center attack (15 reports)
The sequence of 15 MMWR articles after the September 11,
2001, terrorist attacks was the second largest series of reports
related to a single environmental event. The initial overview of
activities in response to the attacks appeared on September 28,
2001 (42). Six of the reports related to occupational concerns:
exposures to workers at and near the site, injury and illness
rates among workers, use of respiratory protective equipment,
and follow-up of first responders’ mental and physical health.
The themes of the initial environmental reports were similar
to those in other disaster settings: community needs assessment; investigations of deaths; and surveillance for injuries and
illness, including a review of syndromic surveillance (43). A
pilot survey of airborne and settled dust in residences did not
find evidence of substantive asbestos exposure, although dust
of pulverized building materials was present (44). Follow-up
reports tracked residents’ respiratory and mental health.
Subsequent publications have addressed these findings more

Supplement

fully and documented the elevated rates of new-onset asthma
and posttraumatic stress disorder; the World Trade Center
Registry was instrumental in enabling a thorough evaluation
of these concerns (45). The ability to publish approximately a
dozen detailed and pertinent follow-up reports about critical
aspects of this disaster in less than a year demonstrates the
unique value of MMWR to meet the need for accurate and
timely information after such disasters.

Discussion
This review of 826 MMWR articles demonstrates the scope
of MMWR’s coverage of environmental health and the remarkable diversity and richness of the field. Over five decades,
MMWR has reported on hazards and diseases both old and
new. A reader of these reports is struck by all the ways that
old and well-known hazards can resurface under unanticipated
circumstances. For example, the MMWR reports on lead and
CO poisoning and pesticides are full of new exposure pathways that constantly surprise. MMWR has been an excellent
resource for highlighting and tracking surveillance data for
environmental diseases (e.g., lead poisoning, CO poisoning,
and asthma) and for reporting biomonitoring results that
demonstrate population exposure trends for cotinine, lead,
mercury, and other substances.
MMWR has been at its best in highlighting and tracking
new outbreaks of disease, unfolding disasters (both natural and
human-made), urgent public health scenarios, and the multiple
ways in which illness and death can occur from exposures to
chemicals and hazards. It is a unique resource for timely updates
of major events (e.g., Mount St. Helens; Hurricane Katrina; the
2001 attack on the World Trade Center, and epidemics, including the outbreak of EMS). It is an effective way to provide
preliminary reports of complex investigations that highlight
important public health messages (e.g., with the 1980 heat
wave investigation or the toxic oil syndrome investigation).
Additionally, it likely represents the most remarkable collection of reports on outbreaks, illness, and death in existence
from pesticides to natural poisons, dietary supplements, home
remedies, chemicals, and consumer products.
Over its five decades at CDC, MMWR reports on
environmental health have focused mostly on acute, high-dose,
clinically apparent, and urgent risks. This analysis of MMWR
reports over 50 years shows this repeatedly — scores of reports
on acute outbreaks related to water pollutants, pesticides, and
CO. During the 50 years, MMWR has focused much less on
chronic, long-term risks from repeated low-level exposures
and the policy and regulatory approaches that society employs
to protect the public from such risks. This is understandable

given that the MMWR weekly, with its traditional short,
telegraphic form, was created to report on immediate threats
to the public health. Authors have generally recognized that,
for analyses that require more complex epidemiologic analyses
and description, long-form peer-reviewed medical and public
health journals are a more conducive forum, although the
MMWR Surveillance Summaries do publish long-form
compendiums of surveillance findings.
In recent years, this has begun to change as authors of longerterm studies have wished to capitalize on MMWR’s appeal to
the news media and the nation’s public health readership. Even
with its short format, the MMWR weekly now often publishes
reports on long-term public health exposures and resultant
illnesses, or on health behaviors. In MMWR’s next 50 years,
as it continues to cover the field of environmental health and
as that field increases in importance even beyond its current
state, MMWR might consider periodic (i.e., monthly or quarterly) reports on environmental health policies, risk analysis,
regulatory approaches, long-term epidemiologic studies, or
other areas that can be meaningfully presented to the broader
public health community. This might further enhance the
critical value of MMWR to the field of environmental health.
Acknowledgments
The contributor thanks Stephen B. Thacker, MD, MSc, for his
always thoughtful and perceptive comments; and C. Kay Smith,
MEd, for her editorial assistance.
References
1. CDC. Lead poisoning—Newark, New Jersey. MMWR 1970;19:358.
2. CDC. Human lead absorption—Texas. MMWR 1997;46:871–7.
3. Landrigan PJ, Baker EL. Exposure of children in heavy metals from
smelters: epidemiology and toxic consequences. Environ Res
1981;25:204–24.
4. CDC. Outbreak of acute lead poisoning among children aged <5
years—Zamfara, Nigeria, 2010. MMWR 2010;59:846.
5. CDC. Blood lead levels—United States, 1999–2002. MMWR
2005;54:513–6.
6. CDC. Carbon monoxide-related deaths—United States, 1999–2004.
MMWR 2007;56:1309–12.
7. Falk H, Creech JL Jr, Heath CW Jr, Johnson MN, Key MM. Hepatic
disease among workers at a vinyl chloride polymerization plant. JAMA
1974;230:59–63.
8. Thomas LB, Popper H, Berk PD, Selikoff I, Falk H. Vinyl chloride
induced liver disease. From idiopathic portal hypertension (Banti’s
syndrome) to angiosarcomas. N Engl J Med 1975;292:17–22.
9. CDC. Angiosarcoma of the liver among polyvinyl chloride workers—
Kentucky. MMWR 1997;46:97–101.
10. CDC. Atypical pneumonia—Spain. MMWR 1981;30:237–8.
11. CDC. Follow-up on toxic pneumonia—Spain. MMWR 1981;30:436–8.
12. CDC. Follow-up on epidemic pneumonia with progression to
neuromuscular illness—Spain. MMWR 1989;31:93–5.
13. Rigau-Pérez JG, Pérez-Alvarez L, Dueñas-Castro S, et al. Epidemiologic
investigation of an oil-associated pneumonic paralytic eosinophilic
syndrome in Spain. Am J Epidemiol 1984;119:250–60.

MMWR  /  October 7, 2011  /  Vol. 60

95

Supplement

14. Kilbourne EM, Rigau-Pérez JG, Heath CW Jr, et al. Clinical
epidemiology of toxic-oil syndrome: manifestations of a new illness. N
Engl J Med 1983;309:1408–14.
15. CDC. Eosinophilia-myalgis syndrome—New Mexico. MMWR 1989;​
38:765–7.
16. CDC. Eosinophilia-myalgia syndrome and L-tryptophan-containing
products—New Mexico, Minnesota, Oregon, and New York, 1989.
MMWR 1989;38:785–8.
17. Swygert LA, Maes EF, Sewell LE, Miller L, Falk H, Kilbourne EM.
Eosinophilia-myalgia syndrome: results of national surveillance. JAMA
1990;264:1698–703.
18. CDC. Asthma prevalence and control characteristics by race/ethnicity—
United States, 2002. MMWR 2004;53:145–8.
19. CDC. Vital signs: nonsmokers’ exposure to secondhand smoke—United
States, 1999–2008. MMWR 2010;59:1141–6.
20. CDC. Aldicarb food poisoning from contaminated melons—California.
MMWR 1986;35:254–8.
21. CDC. Acute convulsions associated with endrin poisoning—Pakistan.
MMWR 1984;33:687–8,693.
22. Agocs MM, Etzel RA, Parrish RG, et al. Mercury exposure from interior
latex paint. N Engl J Med 1990;323:1096–101.
23. CDC. Update: mercury poisoning associated with beauty cream—
Arizona, California, New Mexico, and Texas, 1996. MMWR
1996;45:633–5.
24. CDC. Thimerosal in vaccines: a joint statement of the American
Academy of Pediatrics and the Public Health Service. MMWR
1999;48:563–5.
25. CDC. Serum 2,3,7,8-tetrachlorodibenzo-p-dioxin levels in Air Force
health study participants—preliminary report. MMWR 1988;​
37:309–11.
26. CDC. Health-risk estimates for 2,3,7,8-tetrachlorodibenzodioxin in
soil. MMWR 1984;33:25–7.
27. CDC. Street-drug contaminant causing Parkinsonism. MMWR 1984;​
33:351–2.
28. CDC. Acute public health consequences of methamphetamine
laboratories—16 states, January 2000–June 2004. MMWR 2005;54:356–9.
29. CDC. Deaths associated with a purported aphrodisiac—New York City,
February 1993–May 1995. MMWR 1995;44:853–5,861.

96

MMWR  /  October 7, 2011  /  Vol. 60

30. CDC. Pentachlorophenol poisoning in newborn infants—St. Louis,
Missouri. MMWR 1967;16:334–5.
31. CDC. Cyanide poisonings associated with over-the-counter
medication—Washington state, 1991. MMWR 1991;40:161,167–8.
32. CDC. Barium toxicity after exposure to contaminated contrast
solution—Goias state, Brazil, 2003. MMWR 2003;52:1047–8.
33. CDC. Violations identified from routine swimming pool inspections—
selected states and counties, United States, 2008. MMWR
2010;59:582–7.
34. Public Health Service. Healthy people 2000: national health promotion
and disease prevention objectives--full report, with commentary.
Washington, DC: US Department of Health and Human Services, Public
Health Service, 1991; DHHS publication no. (PHS)91-50212.
35. CDC. Hazardous substances released during rail transit—18 states,
2002–2007. MMWR 2007;56:553–6.
36. Baxter PJ, Ing R, Falk H, et al. Mount St Helens eruptions, May 18 to
June 12, 1980: an overview of the acute health impact. JAMA
1981;246:2585–9.
37. Buist AS, Bernstein RS, eds. Health effects of volcanoes: an approach
to evaluating the health effects of an environmental hazard. Am J Public
Health 1986;76(Suppl):1–90.
38. Glass RI, Craven RB, Bregman DJ, et al. Injuries from the Wichita Falls
tornado; implications for prevention. Science 1980;207:734–8.
39. Kilbourne EM, Choi K, Jones TS, Thacker SB. Risk factors for
heatstroke: a case-control study. JAMA 1982;247:3332–6.
40. Semenza JC, Rubin CH, Falter KH, et al. Heat-related deaths during
the July 1995 heat wave in Chicago. N Engl J Med 1996;335:84–90.
41. CDC. CDC Grand Rounds: radiological and nuclear preparedness.
MMWR 2010;59:1178–81.
42. CDC. New York City Department of Health response to terrorist attack,
September 11, 2001. MMWR 2001;50:821–2.
43. CDC. Syndromic surveillance for bioterrorism following the attacks on
the World Trade Center—New York City, 2001. MMWR 2002;51(special
issue):13–5.
44. CDC. Potential exposures to airborne and settled surface dust in
residential areas of lower Manhattan following the collapse of the World
Trade Center—New York City, November 4–December 11, 2001.
MMWR 2003;52:131–6.
45. Farfel M, DiGrande L, Brackbill R, et al. An overview of 9/11 experiences
and respiratory and mental health conditions among World Trade Center
Health Registry enrollees. J Urban Health 2008;85:880–909.

Supplement

Occupational Epidemiology and the National Institute for
Occupational Safety and Health
William Halperin, MD, DrPH1
John Howard, MD, JD2
1Department of Preventive Medicine and Community Health, New Jersey Medical School, University of Medicine and Dentistry of New Jersey, Newark, New Jersey
2Office of the Director, National Institute for Occupational Safety and Health, CDC, Washington, D.C.
Corresponding author: William Halperin, MD, DrPH, Department of Preventive Medicine and Community Health, New Jersey Medical School and School,
185 South Orange Avenue, MS8, Room F-506, P.O. Box 1709, Newark, NJ 07101-1709; Telephone: 973-972-4422; Fax: 973-972-7625;
E-mail: [email protected].

Introduction
The major factors that propelled the development of occupational epidemiology since the 1950s have been delineated
(1). They include momentum to control occupational injury
that gained national prominence in the wake of the Triangle
Shirtwaist Fire of March 25, 1911, in which 146 young, mostly
female immigrant garment workers fell to their deaths while
escaping from a fire in a locked sweat shop. This tragedy was
a turning point in the nationwide adoption of state-based
occupational safety regulations, workers’ compensation programs, and federal safety legislation. During the 1930s, federal
initiatives in occupational safety and health required contractor
compliance, not only with wage and hour laws, but also with
federal occupational safety and health regulations. The New
Deal built state capacity by funding state industrial hygiene
programs. Levenstein (1) reports a diminution of interest in
occupational safety and health, except for the Atomic Energy
Act in the 1950s, until the 1960s’ resurgence in organized
labor’s political voice. Also, societal reaction to the Farmington,
West Virginia, mine disaster of 1968, which killed 78 miners,
led to passage of the Federal Coal Mine Health and Safety Act
of 1969 and introduced federal regulation and federal inspectors to the mining industry.
To this brief history could be added the major scientific
advances in the invention and commercialization of synthetic
organic chemicals, such as organic dyes that caused epidemics
of bladder cancer among industrial workers and anemia and
leukemia among benzene-exposed workers. Interest among
health-care students and the public probably was affected by
growing concern about the health effects of environmental
toxins communicated to the public through Rachel Carson’s
1962 book, Silent Spring (2). This book vividly detailed the
environmental consequences of pesticides and helped launch
the environmental movement. In 1965, a parallel popular
book by Ralph Nader, Unsafe at Any Speed (3), concerned the
forces at play in industry and society that led to production of
unsafe automobiles and failure to adopt new safety technology,

such as seat belts, which vaulted consumer safety into the
public agenda. These historical tides provided fertile ground
for national-level development of occupational epidemiology
midway through the 20th century.
The institutional genealogy and political history of the
Occupational Safety and Health Administration (OSHA) and
the National Institute for Occupational Safety and Health
(NIOSH) through numerous government predecessor organizations has been delineated by Lynne Page Snyder (L.P.
Snyder, The National Institute for Occupation Safety and Health,
1971–1996: a brief history. Office of the Public Health Service
Historian, 1997, unpublished data). The capstone event for
occupational health in the mid-20th century was passage of
the Occupational Safety and Health (OSH) Act, supported
by President Lyndon Johnson as part of the New Society and
signed into law on December 29, 1970 by President Richard
Nixon, the son-in-law of a miner who died of silicosis. Congress
provided a broad delegation of authority to the Secretary of
Labor to carry out the OSH Act. The OSH Act federalized
regulation and enforcement, including inspections that had
previously been a function of various state governments, and
provided for the first time uniform national enforcement of
occupational safety and health across the United States. It
removed responsibility for inspection and enforcement from
state governments—which sometimes were conflicted in
balancing the interests of health and safety against those of
commercial enterprise and local politics. The OSH Act also
mandated that the federal government gather a critical mass of
scientific expertise across multiple disciplines, such as medicine,
epidemiology, industrial hygiene, safety, health education, and
psychology, to focus exclusively on occupational disease and
injury prevention.
The OSH Act also reshaped the playing field with regard to
epidemiologic investigations. The first change was in providing workers or their representatives and management with
experts who could assess the potential for, or occurrence of,
occupational disease and injury in their workplaces. Before the

MMWR  /  October 7, 2011  /  Vol. 60

97

Supplement

OSH Act, the playing field in many states was far from level.
Employers, especially larger corporations, had the resources to
provide access to occupational health consultants and epidemiologists. It would have been unusual for organized labor and
much less likely for nonunion workers at smaller workplaces
to have the resources to hire such experts. The OSH Act gave
them access to epidemiologic consultation, which was called a
Health Hazard Evaluation (HHE), and the Act was worded to
give them direct access to expertise in the federal government,
thereby bypassing state and local government. The impact
of the NIOSH HHE program was that both workers and
management gained unhindered access to multidisciplinary
occupational health expertise. Workers and small employers
were no longer prevented from obtaining this expertise by
an inability to pay. Also, perhaps most importantly, worksite
problems would now be approached by using a public health
and consultative perspective.
Parallel considerations also led to inclusion in the OSH Act of
research expertise in epidemiology, toxicology, and other fields.
This expertise would provide unbiased information as the basis
for recommendations and regulations on health and safety. To
carry out independent large-scale preplanned research on worker
health and safety (i.e., industrywide studies), the OSH Act gave
NIOSH right of entry into private workplaces and ensured time
and space for examination and interview of workers.
In place of various state-specific activities that previously had
led to disparities in worker protection and health, the OSH
Act standardized the establishment of regulations and periodic
inspection of workplaces across the United States. The Act
also established a rational system to generate and apply new
knowledge relevant to worker safety and health. The OSH Act
led to establishment of OSHA (a regulatory body) and, in April
1971, NIOSH (a research institute). NIOSH was envisioned
as a science-based center dedicated to preventing occupational
disease and injury. It was to have many interrelated functions
that together would serve as a system for the scientific advancement of prevention.
Early on, epidemiology was deemed central to the work of
NIOSH, and it played three major roles. The role most familiar
to the rest of CDC, where NIOSH is located, is field epidemiology. At the request of workers, their labor representative,
management, or state health departments, NIOSH (under the
HHE program) conducts field epidemiologic investigations
of individual workplaces. The field teams can consist of an
epidemiologist, who often is a physician, and industrial hygienists, who are highly skilled in identifying potential workplace
hazards, measuring and controlling levels of exposure, and
identifying appropriate control strategies.

98

MMWR  /  October 7, 2011  /  Vol. 60

A second role for epidemiology is the conduct of large studies, often involving multiple industrial facilities across the
United States, to assess the relationship of exposure and possible
adverse outcomes. Epidemiologic associations sometimes are
postulated by laboratory research in toxicology (also a forte of
NIOSH) and sometimes by the astute observations of workers
and their health-care providers. These large multiplant studies
also assess the shape of the exposure–response relationship.
Understanding the exposure–response relationship is essential
to assessing risk, which is essential to recommending a level of
exposure at which workers will not suffer short-term or longterm illnesses as a consequence of their work (e.g., the risk for
lung cancer from exposure to diesel exhaust in the trucking
industry [4]). Such large-scale studies are not limited to chemical exposure but include the evaluation of best practices for
preventing injuries, such as slips, trips, and falls in hospitals
(5) and other hazards.
The third role for epidemiology in NIOSH’s work is surveillance for occupational disease and injury. The goals of
this surveillance are to estimate the magnitude and trends of
occupational disease and injury, identify new occupational
diseases and injuries, detect sentinel health events that signal
failures of prevention, and develop strategies for targeting alltoo-scarce preventive resources to industries, occupations, and
locations most in need.
Occupational disease surveillance is not new. It is rooted
in the astute observations of Bernardino Ramazzinni (1663–
1714) (6) about the relationship of occupation and disease in
the 17th century, and of Alice Hamilton, a field epidemiologist
and physician (7), who negotiated access to myriad industries
and occupations during World War I and later, was intent on
preventing occupational disease and injury.
Occupational health exists at the border between labor and
management, and government support for preventing occupational injury and disease has waxed and waned with waves
of political change (1). Renewed interest is often generated by
fresh societal concern after occupational disasters with large
numbers of victims, such as the Triangle Shirtwaist Fire of 1911
and the Farmington Coal Mine Disaster of 1968. This MMWR
report provides examples of how NIOSH uses epidemiology to
conduct field investigations in response to requests, to carry out
large-scale investigations to assess causal associations or dose
response relationships, and to maintain surveillance systems
for occupational health and disease.

Supplement

Field Studies in Response to
Requests

of this outbreak by conducting epidemiologic investigations at
other similar plants, by conducting toxicologic studies, and by
recommending regulatory and engineering solutions.

Example: Bronchiolitis Obliterans in
Workers at a Microwave-Popcorn Plant

Overview

In 2002, Kathleen Kreiss, a NIOSH scientist and former
CDC Epidemic Intelligence Service (EIS) Officer, and colleagues reported an outbreak of bronchiolitis obliterans in
workers at a microwave-popcorn production plant that used
diacetyl as a butter flavoring agent (8). In response to a request
from the Missouri Department of Health, which had received
reports of eight former workers from the plant who became ill
during 1993–2000, NIOSH conducted an epidemiologic field
investigation and exposure assessment. In 2000, 117 current
workers completing a symptom questionnaire had 2.6 times
the expected rate of respiratory symptoms, twice the rate of
physician-diagnosed asthma and bronchitis, and 3.3 times the
rate of airways obstruction (10.8 times the rate for nonsmokers). Detailed assessment of exposures in the plant showed a
strong relationship between exposure to diacetyl and current
respiratory disease. As an example of the potential severity of
the disease, according to NIOSH’s investigation, one patient
was a 40-year-old nonsmoking housewife who had begun work
on the packaging line in 1993 and had become symptomatic
with airway disease in 1994. At that time, her forced expiratory
volume was only 24% of normal, and in 1995, she had been
placed on a waiting list for lung transplant.
The prologue to the NIOSH investigation is instructive.
During 1993–1998, several plant workers were seen by two
pulmonary physicians in southwestern Missouri (9). The physicians found fixed airway obstruction and viewed the patients
as atypical in that they worked in the same plant, smoked
minimally or not at all, and did not respond to asthma medications. The pulmonologists referred the patients separately
to national referral centers and expressed concern in one of
their referral letters about similar cases associated with the
same plant. They wrote that they had reported the situation to
OSHA; OSHA inspectors had “visited the plant but concluded
no lung hazards existed” (9).
Meanwhile, the spouse of one worker identified four additional coworkers who were similarly affected. That information
was referred to a lawyer specializing in workers’ compensation,
who consulted an occupational physician, who in turn contacted the Missouri Department of Health. Subsequently, an
experienced environmental health worker called CDC, which
referred the call to NIOSH. A call from the NIOSH investigator
to the Missouri state epidemiologist led to a request to NIOSH
for assistance in a joint investigation. After completing the investigation, NIOSH continued to contribute to the understanding

The Institute of Medicine (IOM) assessed the impact of
field investigations conducted in response to requests from
representatives of workers or industry (10). It described nine
examples of hazards identified during 1978–2006 that resulted
in “wide impacts.” One was the example of diacetyl in the
microwave-popcorn plant. In another example, exposure to
dibromochloropropane (a nematocide previously associated
with sterility in chemical production workers) was assessed
among agricultural workers in several investigations during
1977–1981. OSHA used the findings to set a standard in 1979
limiting occupational exposure. In addition, IOM noted that a
large number (337) of NIOSH investigations of lead exposure
during 1978–1995 “provided information about exposures and
control measures, consultation, and enforcement activities.”
IOM also noted 1) four investigations of silica exposure in the
roofing industry that were cited as the basis for a curriculum
designed to train 20,000 roofers to prevent occupational lung
disease; 2) two investigations of finely ground silica, known
as silica flour, that led to recommendations and regulations
for control of occupational exposure; 3) eight investigations
of flock made of synthetic fiber that was found to cause interstitial pneumonitis; 4) numerous investigations of musculoskeletal disorders that have informed OSHA and “stimulated
major research activities within and outside NIOSH”; and 5)
numerous field investigations by NIOSH demonstrating that
powdered latex gloves were a risk factor for latex allergy, which
played a role in replacing them with powder-free latex gloves.

Preplanned Large-Scale Studies
One of the major responsibilities assigned to NIOSH in
the OSH Act is the conduct of epidemiologic studies of
chronic and low-level exposure to chemicals in industry (i.e.,
industrywide studies). These studies are designed to detect
an increased risk if it truly exists while avoiding a false negative finding resulting from small sample sizes or previously
established exposure controls. Because many chronic diseases
demonstrate latency between exposure and disease onset, the
population studied must have sufficient years of exposure and
sufficient years of follow-up to demonstrate a possible effect.
To demonstrate an exposure–response relationship, which
is critical to assessing causality and in establishing a level of
exposure at which there is no effect, exposure must vary among
cohort members.
MMWR  /  October 7, 2011  /  Vol. 60

99

Supplement

Example: Studies of Mortality from TCDD
During the late 1970s and early 1980s, a confluence of interests led NIOSH to conduct a cohort mortality study of workers exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD),
one of many dioxin congeners. Studies from Scandinavia were
pointing to an association among chemical production workers
between TCDD exposure and excess risk for soft tissue sarcoma and lymphoma. Concern existed for veterans and others
exposed during the Vietnam War to TCDD, an inadvertent
contaminant of the widely used defoliant Agent Orange.
Toxicologic studies were also pointing to an increased risk and
a physiologic mechanism for toxicity, the aryl-hydrocarbon
receptor. In 1980, the U.S. Department of Defense requested
assistance from NIOSH in conducting an epidemiologic study
of soldiers who had served in Vietnam. A recent EIS Officer
(W.H.) and the Director of NIOSH, Tony Robbins, visited the
Pentagon, where they learned of the limited available records
that could be used to accurately characterize the location of
soldiers in Vietnam and their exposure to defoliants. They
concluded that a study in civilian exposed workers was more
likely to be useful than a study among soldiers. The civilian
study could then be applied to Vietnam War veterans.
In 1981, NIOSH began efforts to identify plants in the
United States that produced chemicals contaminated with
TCDD (11). In all, 5,172 workers at 12 plants were included
in a cohort mortality study. An extensive effort was made to
characterize workers’ potential exposure to TCDD at these
plants from job assignment records. TCDD was measured in
serum from a subset of 253 workers. Cause of death on a death
certificate was used as the outcome of interest. Vital status was
ascertained as of the last day of 1987. The duration of exposure
of the cohort members varied: 54% had <1 year of exposure;
29% had 1–5 years; 13% had 5–15 years; and 4% had >15
years. The latency from first exposure was substantial: >20 years
for 61%. The analysis of all workers did not substantiate an
excess risk for lymphoma but found a nonsignificant increase
in soft tissue sarcomas. The analysis of workers with >1 year
of exposure and 20 years of latency indicated a significant
increase in death from lung cancer and soft tissue sarcoma, and
an analysis of all cancers combined also showed a significant
increase. In an updated analysis that extended determination
of vital status and cause of death through 1993 (12), excess
mortality from all cancers was still in excess—a 60% increase
for workers in the highest exposure group. Estimated exposure
for this group was 100–1,000 times higher than for the general
population and similar to doses used in experimental animal
studies that showed cancer excess. The original study (11)
has been cited >400 times and the later study (12) 175 times.
Both studies have been used in risk assessments of national

100

MMWR  /  October 7, 2011  /  Vol. 60

and international importance, in decisions on compensation
of veterans, and for other reasons.

Overview
Only one study—unpublished—has attempted to systematically evaluate the impact of NIOSH’s large-scale epidemiologic
studies (Mary K Schubauer-Berigan. NIOSH, personal communication, 2009). The International Agency for Research on
Cancer has determined that 108 of 900 candidate agents were
known human carcinogens. Schubauer-Berigan reviewed the
literature cited by the International Agency for Research on
Cancer for each occupational metal and fiber to identify the
studies conducted by NIOSH. For epidemiologic studies, the
results were as follows: chromium: three (8%) of 38 studies
were conducted by NIOSH; cadmium: four (13%) of 30;
crystalline silica: seven (28%) of 25; asbestos: 15 (9%) of 160;
beryllium: all of eight.
The spectrum of diseases that NIOSH has studied is broad.
Although a systematic census of studies is not available, examples include studies of cancer of various anatomic sites, cardiovascular disease, neurotoxicity, reproductive disorders, infectious
diseases, and dermatitis. Many of these studies have been used in
part as the basis for risk assessments and standard setting—for
example dioxin, radon, beryllium, silica, and ethylene oxide and
diesel exhaust. Another major focus of NIOSH studies has been
respiratory disease, including those arising from the mining of
coal, uranium, hard rock, cotton dust, vermiculite, and fibers.
Traumatic injury, a major cause of occupational mortality and
morbidity, also has been a major focus; such injuries include
falls, electrocutions, amputations and violence. Industrywide
studies also have focused on occupational sectors, such as construction, agriculture, and child labor.

Surveillance
Surveillance for NIOSH, as for the rest of CDC, follows a
modified version of the definition established by Alexander D.
Langmuir, the first chief epidemiologist of CDC: for NIOSH
it is the systematic collection, analysis, and dissemination of
health-related information for the purposes of prevention or
control of disease or injury (13). NIOSH emphasizes that
occupational surveillance information extends beyond mortality and morbidity to information about injuries, hazards,
and exposures.
NIOSH surveillance studies developed in the 1970s and 80s
under the guidance of Todd Frazier. Frazier and a former colleague from earlier days at Harvard, David Rutstein, and other
NIOSH epidemiologists developed the concept of the Sentinel
Health Event (occupation) or SHE(O) (14). A SHE(O) is “a

Supplement

disease, disability, or untimely death, which is occupationally related and whose occurrence may: provide the impetus
for epidemiologic or industrial hygiene studies; or serve as a
warning signal that materials substitution, engineering control, personal protection, or medical care may be required.”
The SHE(O) list in 1983 comprised 50 conditions linked to
occupational exposure. Rutstein coincidentally was a classmate
in residency with Langmuir at Boston City Hospital, and both
were employed after residency in an epidemiology training
program in New York state. The concept of the SHE(O) led
directly to an invigorated effort to involve selected state health
departments in occupational disease and injury surveillance
and investigation, the Sentinel Event Notification System for
Occupational Risk (SENSOR) Program, which focused on the
surveillance of selected persistent occupational diseases such
as silicosis and lead poisoning. SENSOR was championed by
Edward Baker upon his return to NIOSH in 1987 as Deputy
Director.
NIOSH also established programs for state-based surveillance for occupational injuries, called the Fatality Assessment
and Control Evaluation (FACE), which completed 2,202
investigations in seven targeted topic areas of concern, including electrocutions, confined spaces, falls from elevations,
machinery, child labor, migrant agricultural worker conditions,
and roadway work zones. NIOSH also created the National
Traumatic Occupational Fatality (NTOF) Surveillance System,
a national surveillance system that has provided comprehensive
national data used to target research and prevention efforts,
monitor trends, and identify previously unrecognized risks for
occupational trauma. For example, during the 1980s, NTOF
recognized occupational homicides as a leading cause of death,
accounting for 13% of work-related traumatic deaths (15).

Example: Lead Poisoning in Adults
In 1983, Paul Seligman was assigned to NIOSH as an EIS
officer. To satisfy a training requirement, he evaluated the
potential of the Ohio workers’ compensation system as a source
of information to track the Healthy People 1990 objective
to eliminate occupational lead poisoning (16). At that time,
the incidence of occupational lead poisoning was unknown.
Seligman was concerned that state-based surveillance that
relied on physician reporting led to a woefully undercounted
incidence of lead poisoning in adults. Around this time,
evidence was increasing that lower levels of lead exposure in
young children resulted in cognitive and neurobehavioral
effects. As a result, CDC, the Council of State and Territorial
Epidemiologists (CSTE), and Association of State and
Territorial Health Officials had pushed to institute or amend
state childhood lead poisoning reporting laws nationwide

that required reporting of elevated blood lead levels (BLLs) in
children to the state health departments.
Seligman recalls one of those vibrant moments of profound
insight when he realized that, since all testing for blood lead
in adults had to be done in one of just 70 OSHA-certified
laboratories, using laboratory reporting as the foundation of
surveillance for occupational lead poisoning was very feasible.
Whereas most states focused on childhood lead poisoning,
by 1981, four states (California, New Jersey, New York, and
Texas) had required that all laboratories performing blood lead
assays must report all elevated BLLs in children and adults to
the state health department. In 1986, Seligman worked with
these four states to publish an article in MMWR analyzing
the states’ data on elevated BLLs in adults, the vast majority
of which came from workplace exposures.
To get states to expand their lead reporting requirements to
include adults, Seligman worked with Henry Falk of CDC’s
National Center for Environmental Health to get the issue of
adult lead surveillance on the agenda at meetings of CSTE
and the Association of State and Territorial Health Officials.
Armed with data from the four states and the support of
articulate and persuasive allies in Linda Rudolph (California),
Alice Stark (New York), Dennis Perotta (Texas), and Martha
Stanbury (New Jersey), Seligman and Falk made a strong
case for expanding the reporting of elevated BLLs to include
everyone, not just children. In 1987, NIOSH and CSTE chose
state-based lead poisoning surveillance as the first SENSOR
condition for surveillance by using Seligman’s idea for laboratory-based reporting. The system was called the Adult Blood
Lead Epidemiology and Surveillance (ABLES).
NIOSH supported states using ABLES through cooperative agreements and required reporting of data by laboratories and health-care providers for adults with elevated BLLs.
Supplementary data were subsequently gathered through interviews of workers, employers, and physicians. ABLES spread
to 18 states by 1992, and is now active in 40 states. With the
advent of ABLES, for the first time, data became available on
the incidence, trends, and distribution of occupational lead
poisoning. ABLES allowed estimates of the magnitude of lead
poisoning and its distribution and trends over time and helped
to identify high-risk industries, occupations, and specific
workplaces in need of control measures. For example, ABLES
reported a total of 9,871 cases of occupational lead poisoning
for 2007(17), a decline from 14 per 100,000 employed adults
in 1994 to 7.8 in 2007. Among the 40 participating states,
prevalence rates ranged from 0.8 to 36.4 per 100,000 in the
general population. Exposure at work accounted for about 80%
of cases in adults. Industries with high rates included manufacturing of storage batteries and mining. Nonoccupational
exposure accounted for about 5% of prevalent cases. NIOSH
MMWR  /  October 7, 2011  /  Vol. 60

101

Supplement

and participating states were able to accomplish cooperatively
all the goals of occupational disease and injury surveillance:
estimating the magnitude and trend of disease, describing its
distribution, identifying risk factors, and systematically collecting information useful for informing and providing preventive
measures at specific worksites.

Overview
By working with states and other federal agencies, NIOSH
has helped create an effective patchwork quilt of surveillance
systems for the prevention of occupational disease and injury.
State-based surveillance conducted in 23 states in cooperation
with NIOSH as part of SENSOR now report statistics on 19
occupational health indicators, such as burns, amputations, and
pneumoconiosis. Some states also conduct in-depth surveillance on silicosis, pesticide poisoning, occupational asthma,
musculoskeletal disorders, sharps injuries in hospital workers, injuries among truckers, and fatal injuries among adults
and teens. Surveillance for other conditions is conducted by
NIOSH itself, including cardiovascular disease deaths and traumatic injury among firefighters, radiographic evidence of coal
workers’ pneumoconiosis, death from various pneumoconioses
and malignant mesothelioma. NIOSH also collaborates with
the Consumer Product Safety Commission in surveillance for
occupational injuries in a sample of U.S. hospitals reported in
the National Electronic Injury Surveillance System.

The Future
In 40 years, NIOSH has developed an extraordinary capacity
to carry out 1) field studies in response to requests—in the
tradition of shoe-leather epidemiology 2) large-scale multisite
epidemiologic studies to understand more subtle causal relationships and establish dose–response relationships essential
for assessing risk and recommending safe limits on exposure;
and 3) surveillance for occupational diseases and injuries of
national interest. Tribute for this accomplishment goes to the
scores of epidemiologists whose careers have been spent in
these efforts, to the leaders of NIOSH and CDC through the
decades who understood that effective prevention of occupational disease and injury needs strong epidemiologic capacity in
NIOSH, to Executive Branch and Congressional leaders who
facilitated these efforts, and to progressive leaders of organized
labor and industry.
Major challenges remain in epidemiology’s contribution to
preventing occupational disease and injury. One challenge is
how to ensure the safety of new advances in commerce. For
example, NIOSH is playing a leadership role in innovating an
epidemiologic strategy for the advances in nanotechnology.

102

MMWR  /  October 7, 2011  /  Vol. 60

Such anticipatory planning has not always been done in the
past before the widespread adoption of new industrial technologies. For example, if the dangers of asbestos had been
recognized before it was widely used, many major health
consequences could have been avoided. Today, the early use of
epidemiologic investigations can help reduce uncertainty about
risks for occupational diseases and injuries as new industrial
methods advance, even when adverse consequences of new
technologies prove unfounded (e.g., early speculation about
the possibility of cataracts or spontaneous abortion after using
video display terminals).
A second challenge relates to NIOSH’s role within the larger
framework of prevention of occupational disease and injury in
the United States. In contrast to the U.S. system for preventing infectious diseases, in which CDC’s state partners have
substantial resources, states have only marginal resources in
the occupational health arena. Through a century of NIOSH
and its predecessors, the federal government has been key to
providing resources to enable states to develop capacity for
occupational health and safety (L.P. Snyder. The National
Institute for Occupation Safety and Health, 1971–1996: a brief
history. Office of the Public Health Service Historian, 1997,
unpublished data).
A third challenge is development and distribution of
expertise. To understand this challenge, one can go back to
Langmuir’s original conceptualization of the EIS. One goal was
enhancement of federal epidemiologic expertise. Another was
to salt academic and health-care centers across the country with
EIS graduates who would enhance disease prevention locally
through the use of epidemiology. To be effective nationally
in preventing occupational injury and disease, NIOSH must
continue to be able to support a system for training experts,
who will migrate to schools of medicine and public health and
state and local health departments and who will train others. In
addition, to sustain trainers, a robust support system is needed
to sustain careers outside of NIOSH.
A fourth major challenge is expressed in a fundamental principle espoused by former CDC Director William Foege—that
the world is a lifeboat inhabited by all peoples of all nations.
With globalization, many industries and their inherent hazards to workers have moved overseas, often to countries where
occupational safety and health are not considered important.
Increasingly, the United States is accepting a role in ensuring that imported products are made to be safe, not just for
U.S. consumer, but also for the workers who manufacture
them overseas. One method to ensure health and safety is by
developing international training programs, particularly in
occupational epidemiology and industrial hygiene.
The ultimate challenge for NIOSH is to not only effectively control occupational diseases and injuries that are the

Supplement

remnants of the last century, but also to preempt new hazardous exposures and conditions from gaining a foothold in the
new century.
Acknowledgements
A profound expression of gratitude is due to Chuck Levenstein
who is well known for providing a panoramic view of the societal
issues shaping occupational safety and health, and to Lynne Snyder,
an outstanding historian of modern public health. Many colleagues
offered valuable review, facts, thoughts, advice, and text. In alphabetic
order they include Robert Castellan, Marilyn Fingerhut, Kathleen
Kreiss, Mary Schubauer-Berigan, Paul Seligman, John Sestito, Terresa
Schnorr, Leslie Stayner, Kyle Steenland, Nancy Stout, Allison Tepper,
and David Weissman.
References
1. Levenstein C, Wooding J, Rosenberg B. Occupational health: recognizing
and preventing work-related disease and injury. 4th ed. Philadelphia,
PA: Lippincott Williams and Wilkins; 2000.
2. Carson R. Silent spring. New York, NY: Houghton Mifflin; 1962.
3. Nader R. Unsafe at any speed: the designed-in dangers of the American
automobile. New York, NY: Grossman; 1965.
4. Steenland K, Deddens J, Stayner L. Diesel exhaust and lung cancer in
the trucking industry: exposure–response analyses and risk assessment.
Am J Ind Med 1998;34:220–8.
5. Bell JL, Collins JW, Wolf L, et al. Evaluation of a comprehensive slip,
trip, and fall prevention programme for hospital employees. Ergonomics
2008;51:1906–25.
6. Ramazzini B. De morbis artificum diatriba [diseases of workers], 1713.
Am J Public Health 2001;91:1380–2.
7. Hamilton A. Exploring the dangerous trades: the autobiography of Alice
Hamilton, M.D. Evanston, IL: Northwestern University Press; 1985.

8. Kreiss K, Goma A, Kullman G, Fedan K, Simoes E, Enright P. Clinical
bronioloitis obliterans in workers at a microwave-popcorn plant. N Engl
J Med 2002;347:5.
9. Kreiss K. Flavoring-related bronchiolitis obliterans. Curr Opin Allergy
Immunol 2007;7:162–7.
10. Committee to Review the NIOSH Health Hazard Evaluation Program,
National Research Council. The Health Hazard Evaluation Program at
NIOSH. Washington, DC: National Academies Press; 2009. Available
at http://www.nap.edu/catalog.php?record_id=12475.
11. Fingerhut M, Halperin W, Marlow D, et al. Mortality among U.S.
workers employed in the production of chemicals contaminated with
2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). N Engl J Med
1991;324:212–8.
12. Steenland K, Piacitelli L, Deddens J, Fingerhut M, Chang L. Cancer,
heart disease, and diabetes in workers exposed to 2,3,7,8-tetrachlorodibenzop-dioxin. J Natl Cancer Inst 1999;91:779–86.
13. CDC. Tracking occupational injuries, illnesses, and hazards: The NIOSH
surveillance strategic plan. Atlanta, GA: National Institute for
Occupational safety and Health, CDC. Available at http://www.cdc.
gov/niosh/docs/2001-118/pdfs/2001-118.pdf.
14. Rutstein D, Mullan R, Frazier T, Halperin W, Melius J, Sestito J. The
sentinel health event (occupational): a framework for occupational health
surveillance and education. J Am Pharm Assoc 1983;73:1054–62.
15. Bell CA, Stout NA, Bender TR, Conroy CS, Crouse WE, Myers JR.
Fatal occupational injuries in the United States, 1980–1985. JAMA
1990;263:3047–50.
16. US Department of Health, Education, and Welfare. Healthy people:
the Surgeon General’s report on health promotion and disease prevention.
Washington, DC: US Department of Health, Education, and Welfare;
1979. DHEW publication no. (PHS)79-55076.
17. CDC. Adult Blood Lead Epidemiology and Surveillance—United States,
2005–2007. MMWR 2009:58;365–9.

MMWR  /  October 7, 2011  /  Vol. 60

103

Supplement

Trends in Global Health and CDC’s International Role, 1961–2011
Kevin M. De Cock, MD
Center for Global Health, CDC, Atlanta, Georgia
Corresponding author: Kevin M. De Cock, MD, Center for Global Health, CDC, MS D69, 1600 Clifton Road, N.E., Atlanta GA 30329-4018; Telephone
404-639-0119; Fax: 404-639-7490; E-mail: [email protected].

Introduction
In late August 2007, Dr. Peter Kilmarx, a CDC epidemiologist working on HIV/AIDS, awoke at his home in Atlanta to
read a text message on his mobile phone. The message, sent
the night before, was from Gilbert Shamba Mayi, the chief of
Bakawa Tombe, a small village in Kasai Occidental Province
in the Democratic Republic of Congo. Dr. Kilmarx had met
the chief approximately 20 years earlier while serving in the
Peace Corps. The message said in a local Congolese language,
“Bakwa Tombe greets you with pleasure. There is a lot of death
from Ebola. When are you coming for the hospital? How are
you Peter? Chief Gilbert Shamba Mayi.”
This real time text message from a “citizen epidemiologist” in
a remote Congolese village led to deployment of a CDC team
to the affected area in less than 2 weeks, and they determined
quickly that the cause of the outbreak was Ebola hemorrhagic
fever. Compare this anecdote to an experience of the author
of this article, Dr. Kevin DeCock, while he was an Epidemic
Intelligence Service Officer 21 years earlier in 1986. A severe
outbreak of yellow fever started in Benue State, Nigeria, during the middle of 1986 and had already peaked by the time it
came to national attention in October of that year. An outbreak
investigation by an international team began in December.
By the time the international team arrived, approximately
40,000 yellow fever infections and 5,000 deaths had already
occurred (1).
The contrast between these two anecdotes vividly shows
how technological change has affected the way CDC and
other U.S. agencies do their global work. Large-scale social
and technologic changes have wrought changes in international
public health practice and these changes will continue, or even
speed up, in the future.
One example of these changes is a recent increase in the
level of priority accorded to international activities at CDC.
Shortly after assuming his role as Director of CDC in 2009,
Dr. Thomas Frieden identified five priorities for the agency.
One of them was to increase CDC’s impact in global health.
To support this objective, he created the Center for Global
Health, reflecting the increased importance of global health in
general, the relevance of global health to health in the United

104

MMWR  /  October 7, 2011  /  Vol. 60

States, and the increased international role of CDC. In this
same vein, the U.S. Department of State recently released The
First Quadrennial Diplomacy and Development Review: Leading
through Civilian Power (2), which emphasized the increased
international importance of different civilian agencies whose
traditional mandates have primarily been domestic.
As MMWR celebrates its 50th year at CDC, a review of
MMWR articles provides evidence that CDC’s global activities have become firmly established as part of the agency’s core
work. Electronic searching of MMWR articles for the words
“international” or “global” found only five articles mentioning them in 1983, compared with 130 articles in 2010. CDC
responded to five international requests for epidemiologic
assistance (“Epi-Aids”) before MMWR came to CDC in 1961
and to 534 such requests through January 2011.

Evolution of Global Health:
Tropical to International to Global
The term global health has replaced such earlier names as
international health and tropical medicine. These labels reflect
the evolution in scale and scope of the subject and of the work
of diverse agencies, including CDC, since the 1960s and of
their broader mission and activities. The concept of global
health has evolved during the past 50 years from a narrow
view of ecologically and geographically restricted health challenges to a broad and comprehensive approach to health in
the world as a whole.
Tropical medicine developed in the late 19th and early
20th centuries, an era when many countries of the Southern
Hemisphere were colonized by countries of the Northern
Hemisphere. It focused on diseases associated with warm
climates, many of which were parasitic (e.g., malaria, sleeping
sickness, and schistosomiasis). Together with epidemic-prone
viral or bacterial diseases, such as yellow fever, typhoid, and
dysentery, these tropical diseases were recognized early on as
common causes of death and major threats to public health. To
prevent and treat these diseases, training in tropical medicine
became a priority for institutes preparing northern professionals for overseas service.

Supplement

The term international health became widely used after
colonial independence and was accompanied by a change in
focus toward aid and humanitarian assistance to countries of
the developing world. Infectious and parasitic diseases, maternal and child health, and nutrition were the most common
components of these early international health efforts.
Global health now encompasses tropical medicine and international health but extends beyond them in diverse ways (3).
It broadens the agenda internationally and considers health
at the global level. For example, it includes strengthening and
supporting systems required to implement health interventions
and mechanisms for coordination of public health activities.
It includes health education and prevention and extends to
oversight of clinical services appropriate for the local impact
of disease. Global health recognizes the reality of globalization and prioritizes public health challenges that transcend
individual country boundaries and require collective action,
such as threats from infectious agents like HIV, but also from
environmental and climate change; rapid and widespread
urbanization; and changes in socioeconomic conditions, diet,
and lifestyles. Global health is guided by epidemiologic science and research and has as core values concepts of justice,
decency, human rights, and health equity. It also recognizes
the overwhelming relevance and importance of policy, politics,
and diplomacy.

Trends in Global Health, 1961–2011
Advances in global health and science since MMWR was
established at CDC have been extraordinary (Table 1). Two
infectious agents, smallpox in humans and rinderpest in cattle,
have been eradicated. Enormous progress has been achieved
toward the eradication of poliomyelitis and dracunculiasis (i.e.,
guinea worm disease). Polio remains endemic in only four
countries (India, Nigeria, Afghanistan, and Pakistan), and cases
in 2010 were at an all-time low: 1,292 total (232 in countries
where polio is endemic and 1,060 in countries where polio
is not endemic) (4). Reports of guinea worm disease in 2010
were lower than ever before (<2,000), from only five remaining
affected countries (Chad, Ethiopia, Ghana, Mali, and Sudan).
A host of new or drug-resistant pathogens and associated diseases have been described, with resulting outbreaks of varying
severity and distribution that emphasize the necessity for public
health preparedness. The most acutely lethal have been the
hemorrhagic fevers caused by such agents as Lassa, Marburg,
and Ebola viruses, but certain sexually transmitted (HIV)
and airborne-transmitted (severe acute respiratory syndrome
[SARS], multidrug- and extensively drug-resistant tuberculosis
[TB]) agents have had greater public health impact.

A large number of policy initiatives were launched, new
bodies established, influential reports published, and philanthropic foundations created, all contributing to a fundamental
realignment of global health architecture and governance. At
the start of the 21st century, the global community committed
to the Millennium Development Goals (MDGs), of which
three were specifically devoted to health (MDGs 4, 5, and
6, relating, respectively, to child health; maternal health; and
HIV, TB, and malaria).
Other MDGs focusing on economic development have
considerable implications for health, most directly MDG 7
relating to environmental sustainability. Progress has been
made toward reducing the proportion of persons without
access to safe drinking water, currently almost one billion
people, but little progress has been made in increasing access
to sanitation. In 2008, 69% and 64% of the population of
southern Asia and sub-Saharan Africa, respectively, lacked
access to basic sanitation (5). Forty-four percent and 27% of
persons in these regions, respectively—approximately 1.1 billion persons—had to resort to open defecation, an affront to
human dignity (5). That settings exist today where humans
have greater access to mobile phones than to toilets reflects
unfavorably on globalization.
The World Health Organization (WHO) embraced the
goal of malaria eradication in 1955, but this ambitious
aspiration was abandoned in the late 1960s in the face of
technical and social challenges. During the past few years, the
President’s Malaria Initiative, the Global Fund to Fight AIDS,
Tuberculosis, and Malaria, and other donors have begun to
address the estimated 225 million cases of malaria and almost
781,000 deaths annually (2009 estimates) (6). The focus has
been on delivering artemesinin-based combination therapies,
better diagnostics, insecticide-treated bednets, indoor residual
spraying, and interventions for malaria in pregnancy to millions of persons at risk.
As its name suggests, the Global Fund to Fight AIDS,
Tuberculosis, and Malaria was developed to address these
three diseases that have so disproportionately affected global
health, particularly in sub-Saharan Africa. In addition, the
President’s Emergency Plan for AIDS Relief (PEPFAR), the
largest bilateral health program ever mounted, has contributed an unprecedented U.S.$32 billion thus far to the fight
against HIV/AIDS, including against HIV-associated TB (7).
Currently, approximately 5.2 million HIV-infected persons in
low- and middle-income countries are accessing antiretroviral
therapy compared with <400,000 in 2003 (8). Despite remaining the leading infectious disease challenge in global health,
the HIV/AIDS epidemic has stabilized, and investments in
addressing it are beginning to pay visible dividends in other
spheres of health.
MMWR  /  October 7, 2011  /  Vol. 60

105

Supplement

TABLE 1. Selected achievements and milestones in global health, 1952–2011
Year
1952–1965
1962
1961, 1962, 1963
1964
1965
1967
1969
1970–2002
1970–2010
1974
1976
1976
1977
1978
1979
1980
1981
1983
1984
1984
1985
1986
1986
1988
1993
1994
1995
1995
1995
1996
1996
1997
1998
2000
2000
2000
2000
2001
2001
2002
2003
2003
2003
2005
2005
2005
2005–2010
2008
2008
2009
2009
2010
2010
2010

Event
Global Yaws Control program, jointly sponsored by WHO and UNICEF, reduces yaws prevalence by 95%.
CDC becomes involved in smallpox eradication program (http://www.cdc.gov/about/history/timeline.htm).
Oral polio vaccine licensed in the United States.
First US Surgeon General’s report on tobacco and health published.
First report on diabetes issued by WHO.
First heart transplant performed by Christiaan Barnard in South Africa.
International Health Regulations (cholera, plague, smallpox, yellow fever) launched by WHO.
World child mortality rate down approximately 45% (2003 World Health Report).
World child mortality rate declines approximately 52%.
Onchocerciasis (river blindness) initiative launched in western Africa by WHO, the World Bank, the UN Development Program, and the Food and
Agriculture Organization; 18 million children spared disease; 600,000 cases of blindness averted.
Ebola virus first identified in Sudan and Zaire (now Democratic Republic of Congo).
Legionnaires disease recognized.
Essential Medicines List developed; 156 countries today maintain list.
The Alma-Ata Declaration of 1978 issued at the International Conference on Primary Healthcare convened by WHO. The declaration became a
major milestone in the field of public health. It identified primary health care as a critical element to achieve.
Smallpox eradication declared.
Combating Communicable Diseases Program developed by US Agency for International Development.
First case descriptions of what would become known as AIDS published in MMWR.
HIV identified by coworkers from Institut Pasteur, leading to Nobel Prize in Physiology or Medicine in 2008.
Projet SIDA established in Zaire (now Democratic Republic of Congo).
Bhopal, India, environmental disaster occurs.
Inaugural CDC Field Epidemiology Training Program (later Field Epidemiology and Laboratory Training Program) launched in Thailand.
Chernobyl, USSR (Ukraine), environmental disaster occurs.
WHO’s first program on HIV/AIDS established.
Global Polio Eradication Initiative launched as a result of a resolution passed by the World Health Assembly in 1988 calling for the eradication of
polio by 2000.
World Bank World Development Report, Investing in Health, published.
Polio elimination certified in the Americas.
Directly Observed Therapy–Short Course program for tuberculosis management launched by WHO.
International Commission for Dracunculiasis (guinea worm disease) established.
Joint UN Global Programme on HIV/AIDS established.
“Final rule” on folic acid flour fortification published by US Food and Drug Administration.
Combination antiretroviral therapy highlighted at International Conference on AIDS in Vancouver, British Columbia, Canada.
Highly pathogenic H5N1 first described in humans (infected through contact with infected birds) in Hong Kong.
Global Youth Tobacco Survey (WHO–CDC initiative) established.
UN General Assembly Special Session on HIV/AIDS held.
Millennium Development Goals set by the UN as part of the UN Millennium Declaration in 2000.
Bill and Melinda Gates Foundation established.
International Conference on AIDS held in Durban, South Africa, to highlight AIDS in Africa.
Measles control initiative launched jointly by the American Red Cross, UN Foundation, CDC, UNICEF and WHO.
WHO Global Strategy for Containment of Antimicrobial Resistance established.
Global Fund established.
SARS erupts and is controlled.
US President’s Emergency Plan for AIDS Relief announced.
Joint UN Global Programme on HIV/AIDS/WHO “3 by 5” initiative launched to provide ART to 3 million persons with HIV/AIDS in low- and
middle-income countries by the end of 2005.
International Health Regulations revised.
Partnership for Maternal, Newborn and Child Health created through the collaboration of the Partnership for Safe Motherhood and Newborn
Health (WHO); the Healthy Newborn Partnership (Save the Children USA); and the Child Survival Partnership (UNICEF).
US President’s Malaria Initiative established.
HIV/AIDS progress reported. Widespread availability of ART and prenatal interventions reduce vertical transmission; male circumcision
demonstrated to reduce transmission; access to HIV testing and counseling improved; novel research into preventatives; (e.g., vaginal gel
antiretroviral pills).
WHO report on strengthening of health systems, Everybody’s Business, released.
Report on the Social Determinants of Health issued by WHO.
Global Health Initiative announced by US President Obama
Earthquake in Haiti and subsequent cholera epidemic occur.
Severe lead poisoning outbreak occurs in Zamfara State, Nigeria.
Meningitis vaccine launched in “meningitis belt” (Burkina Faso).
Global Polio Eradication Initiative Strategic Plan 2010–2012 released. CDC prepares first quarterly risk assessment for Independent Monitoring
Board, which conducts first review of progress toward meeting Global Polio Eradication Initiative milestones.

Abbreviations: WHO = World Health Organization; UNICEF = United Nations Children’s Fund; UN = United Nations; SARS = severe acute respiratory syndrome;
ART = antiretroviral therapy.

106

MMWR  /  October 7, 2011  /  Vol. 60

Supplement

Important demographic changes during the past 50 years
have resulted from changing trends in child, maternal, and
adult death rates. These rates reflect changing patterns of disease secondary to economic development and specific public
health interventions. Child and maternal death rates have been
the most important and widely used indicators of health in
different countries. In 2008, 7.95–8.8 million deaths occurred
among children <5 years of age, compared with 11.9 million
deaths in 1990 and approximately 16 million deaths in 1970
(9). Thirty-three percent of these deaths occurred in southern
Asia and 50% in sub-Saharan Africa, with the highest death
rates for children aged <5 years found in western Africa.
Rates in all components of mortality in children aged <5
years (neonatal, postneonatal, and childhood) are declining,
but unequally. Decline has been faster in rates of postneonatal
and childhood mortality than neonatal mortality, most likely
reflecting investment in preventive services, such as vaccination and malaria prevention, as well as better prevention and
management of diarrheal diseases, respiratory infections, and
HIV/AIDS. The reduction in global measles-related mortality,
estimated at 78% during 2000–2008, has been especially striking. As a consequence of these trends, neonatal mortality, often
associated with the same factors as maternal mortality (itself
highest in sub-Saharan Africa and southern Asia), accounts for
an increasing proportion of deaths in children aged <5 years. As
many as 51% of deaths prevented in children <5 years might
be attributable to increased education of reproductive-aged
women (10).
MDG 5 calls for a 75% reduction in the global maternal
mortality ratio from 1990 to 2015. Despite pessimism around
this objective, which depends on access to clinical services
that include emergency obstetric care, maternal deaths have
decreased from an estimated 526,300 in 1990 to 342,900 in
2008 (11). The corresponding reduction in the maternal mortality ratio was from 320 to 251 per 100,000 live-born infants,
suggesting that despite this improvement, MDG 5 was unlikely
to be met by 2015. MDG 5 also called for universal access to
services, such as family planning, in which progress has stalled.
The focus of the health-related MDGs on maternal and child
health obscures major trends and underlying causes of adult
mortality. However, preventable adult mortality has become
a key indicator of health in many countries, reflecting the
emerging pandemic of noncommunicable diseases and injuries. By 2010, two deaths occurred among adults aged 15–64
years for every death among children <5 years of age globally,
and the ratio is even higher for adults <70 years of age: three
deaths among adults to every one death among children (12).
Despite marked regional variations and confounders, such as

HIV/AIDS and its treatment, these trends toward an increasing ratio of deaths in adults apply worldwide, and they apply
disproportionately to males.
These broad mortality trends do not reveal some of the
major shocks that caused substantial disruption at the local
or regional level. One example is HIV/AIDS, which has had
devastating impact in eastern and, especially, southern Africa,
causing massive loss of life expectancy. Global HIV incidence
is considered to have peaked around 1996 and has declined
since then (9). AIDS-related mortality most likely peaked in
2004. Another example is increased mortality in the former
Soviet Union during the 1990s. This increase was caused by
profound social and political change, and the resultant mortality was at the level usually associated with war and conflict in
numerous low- and middle-income countries.

CDC’s Role in Global Health
CDC’s current global health activities build on the momentum developed through historical collaborations in the eradication of smallpox and continue as global partners strive to fulfill
MDGs. CDC’s programs are designed to achieve substantial
and positive health outcomes through enhanced health security and strengthened health systems around the world. The
agency’s global work is characterized by evidence-based public
health actions and extensive collaboration with in-country
partners and international organizations. These partnerships
address in-country needs in surveillance, research, workforce
development, and laboratory capacity (Figure).
Partnerships are the cornerstones of CDC’s global work. In
addition to collaborating with sister agencies in the federal
government, CDC’s principal partners in global health are ministries of health (MOHs) and agencies of the United Nations,
especially WHO and the United Nations Children’s Fund
(UNICEF). In addition, CDC works directly with specific
in-country nongovernment organizations and health institutes.
With CDC offices in 41 countries, and staff assigned to 51
countries, the agency provides technical assistance, mentoring,
and emergency surge capacity directly to MOHs and through
WHO to build national and regional capacity.
Examples of CDC’s direct assistance to MOHs include the
agency’s HIV/AIDS programs and global disease-detection
activities. CDC’s Division of Global HIV/AIDS (formerly
called the Global AIDS Program) provides direct, peer-topeer, technical, financial, and program delivery assistance
to MOHs. This assistance includes collaborations to build
sustainable public health information, laboratory, and management systems. Multiagency work requires interdisciplinary

MMWR  /  October 7, 2011  /  Vol. 60

107

Supplement

FIGURE. Public health framework for health systems strengthening
at CDC

Evidence-based
public health
actions
Ministries of Health/
Public health
institutions
Surveillance
& Health
Information
Systems

Research

Workforce

Laboratory

collaboration between clinicians, epidemiologists, health educators, and other scientists, an example of which is the “Basic
Care Package.” Developed by CDC in 2008, the package
combines interventions (antibiotic medication, insecticidetreated bednets, services for screening and management of
sexually transmitted infections, prevention of maternal-tochild transmission services, and a safe water tool) that have
dramatically reduced illness and improved the quality of life for
persons with HIV in Uganda, Ethiopia, Cote d’Ivoire, Kenya,
Nigeria, Malawi, Rwanda, Uganda, Vietnam, and Zambia.
Through PEPFAR, CDC and its global partners have provided
care to >11 million persons affected by HIV/AIDS, including
3.8 million orphans and vulnerable children. More than 3.2
million persons are alive and 114,000 infants are HIV free
because of this aid (7).
CDC also responds to MOH requests to assist with the
identification and containment of infectious diseases and
other health threats. Almost all of CDC’s national centers
have participated in rapid outbreak investigations, pathogen
discovery, training, and networking. During the past decade,
CDC has played a lead role investigating and responding to
such global threats as pandemic influenza A (H1N1) 2009
and SARS. During 2010, CDC’s Global Disease Detection
program coordinated the response to 14 direct requests from
MOHs for technical assistance related to health threats, including cholera in Haiti and the Dominican Republic, hepatitis
E virus in Uganda, lead poisoning in Nigeria, meningitis in
Ghana, nodding disease in Uganda and southern Sudan, and
polio in the Democratic Republic of Congo.
CDC also partners extensively with multilateral global health
organizations. WHO is a key collaborator. Currently, 29 CDC
staff members are seconded to WHO headquarters and regional
programs, providing expertise in areas such as HIV/AIDS,
influenza, meningitis, measles, polio, immunization, sexually

108

MMWR  /  October 7, 2011  /  Vol. 60

transmitted infections, and TB. These partnerships not only
provide technical assistance from CDC to agency partners
but also create opportunities for CDC to learn directly from
communities in-country. For example, CDC staff are currently
working as part of the Pan American Health Organization
regional Global Water, Sanitation and Hygiene Program cluster
in Haiti, learning how tools such as CDC’s Safe Water System
can be adapted for use in postearthquake Haiti.
Disease surveillance is the foundation for evidence-based
public health action, and enhancing global surveillance systems
is the foundation of CDC’s global health programs. One of
CDC’s core global health missions is to share its expertise,
raising the level of global health surveillance. The agency trains
staff members from partner organizations in the process of
collecting, analyzing, interpreting, and disseminating healthrelated data to better inform solutions globally. CDC and its
partners use these data to determine potential interventions;
monitor their impact; and determine at-risk populations,
disease trends, and potential interventions.
In recent years, CDC has assisted in strengthening several
surveillance efforts around the world. For example, CDC’s surveillance role is highlighted in the President’s Malaria Initiative.
CDC advises the U.S. Malaria Coordinator on priorities for
surveillance strategies and processes. In 2010, other examples
of CDC’s global surveillance work included hand, foot, and
mouth disease and Salmonella enterica serovar Enteriditis in
the People’s Republic of China; human influenza A (H5N1)
infection and Q fever in Egypt; dengue, respiratory syncytial
virus, and febrile encephalitis in Guatemala; micronutrients
and malnutrition in Jordan, Dominican Republic, and Uganda;
and tobacco use among teens and adults in Latin America.
CDC also is involved in research that supports global public health action. The recently released WHO guidelines for
TB screening and prevention in persons with HIV infection
(13) illustrates how CDC’s investment in science influences
global health policy and improves health outcomes. Research
conducted by CDC in Thailand, Cambodia, and Vietnam
in collaboration with the U.S. Agency for International
Development and other partners led to more accurate screening for TB so that TB can be diagnosed and treated earlier
in persons with HIV infection (13). In another example,
CDC collaborated with UNICEF and in-country partners to
conduct research on the prevalence of sexual violence against
women and girls in Swaziland. The study found that one in
three respondents had experienced sexual violence before 18
years of age. The results led to critical policy and programmatic
actions, including establishment of child-friendly courts and
integration of Domestic Violence and Sexual Offenses units
into 75% of police stations in Swaziland.

Supplement

CDC enhances global public health capacity through incountry workforce development. For approximately 30 years,
CDC has invested in developing the skills of the global public
health workforce. Through its signature training program, the
Field Epidemiology Training Program (FETP), CDC works
with MOHs and other partners to train skilled epidemiologists
worldwide. Its specialized laboratory track, Field Epidemiology
and Laboratory Training Program (FELTP), provides training
and support for enhanced in-country laboratory disease surveillance and outbreak response. Through FETP and FELTP,
CDC has helped establish 35 self-sustaining programs that
have produced approximately 2,100 graduates from 51 countries. The graduates have become leaders of MOHs, reducing
dependence on foreign health assistance. Examples of this
transition can be found in a recent response to Rift Valley fever
in Kenya. In an outbreak during 1997–1998, CDC provided
primary leadership for the investigation. In a subsequent outbreak during 2006–2007, primary leadership for the response
was provided by staff in Kenya who had trained through the
Kenya FELTP, which is implemented jointly with CDC and
is now led by Kenyan graduates.
During the past 20 years, CDC also has invested in
development of public health management and leadership
capacity globally. Through CDC’s Sustainable Management
Development Program, CDC works with MOHs and other
partners to strengthen managers’ skills and competencies,
improve program operations, and promote changes in policy
and health systems.
CDC increases laboratory capacity and extends global laboratory systems. In addition to training laboratorians through
FETLP, CDC works alongside its partners to build laboratory capacity and systems. For example, CDC is the founding member, and chairs the steering committee, of PulseNet
International, an international network of seven national and
regional laboratory networks dedicated to tracking foodborne
infections worldwide. Currently, PulseNet is partnering with
reference laboratories throughout the world to build capacity for molecular surveillance of foodborne infections. It has
increased collaboration between international reference laboratories through the addition of 82 new member countries
since 1996 and collaborated in the advancement of detection,
investigation, and control methods of international outbreaks
of foodborne infections.
After the devastating earthquake in Haiti on January 12,
2010, CDC deployed staff to rebuild Haiti’s laboratory capacity. Haiti’s national laboratory was one of the few public health
structures in the nation’s capital to survive the disaster, but
it lacked key supplies and training to detect potential health
threats likely to follow the earthquake. CDC and its partners

quickly provided equipment, rapid diagnostic tests, and training to Haiti’s laboratory technicians. Enhanced capacity has
resulted in increased submissions of specimens to the national
laboratory; an average of 181 bacteriologic tests are performed
each month to confirm diagnoses of diseases ranging from
leptospirosis to meningococcal meningitis. As a result of rapid
laboratory strengthening in Haiti, the country’s National Public
Health Laboratory was able to identify cholera cases within
days after the outbreak began.

Future Trends in Global Health
These three broad themes provide the framework for CDC’s
current work around the globe: enhancing public health capacity, increasing health security, and maximizing health impact
from programs and interventions (Figure). CDC’s future role
will continue within this framework with a goal to create
increasing in-country public health capacity and independence.
CDC hopes to create an analogous relationship between CDC
and its global partners that the agency currently has with its
domestic state public health partners. CDC has seen its role
with U.S. state health departments change from intense engagement initially to a consultative role where local capacity is well
established. In a globalized environment, interactions between
CDC and its MOH partners may increase, but the scope and
intensity of CDC engagement in any country should change
to consultation as national and local public health expertise
develops. The development and strengthening of national
public health institutes globally is a clear step in this direction
(14) Country leadership is prioritized by CDC through all its
global programs, including PEPFAR and the agency’s leadership activities related to the Global Health Initiative.
Despite the unfulfilled commitments relating to the MDGs
and infectious diseases, global health discourse and donor
prioritization will be influenced by geopolitical and socioeconomic changes. Financial downturn and political changes in
donor countries may tighten budgets for health programs for
years to come. An emphasis on integration and systems models
broadens and strengthens specific disease initiatives. Many
countries are in positions to devote more resources to health
than they have previously. Some middle-income countries have
emerged as leaders in debates around such issues as intellectual
property and health policy and could contribute more to global
health financially than they currently do.
Discussion will continue about the relative roles and interaction of public health and development internationally. Both
are necessary, and neither alone can guarantee sustained health
or address all health challenges in a timely and comprehensive
manner. Perhaps the most acute test of how well development

MMWR  /  October 7, 2011  /  Vol. 60

109

Supplement

and public health collaborate and deliver results is the ongoing
situation in Haiti as it recovers from the 2010 earthquake and
cholera epidemic. Only time will determine whether Haiti
emerges from these shocks a stronger and healthier society with
better basic infrastructure, such as for water and sanitation.
The disproportionate effect of disease and early death in
sub-Saharan Africa inevitably means that much attention of
the global health community will focus on that subregion.
Discussion is needed about how best to use resources, including
the balance between addressing high rates of disease affecting
small populations versus large populations with modest rates
that have large numbers of persons affected because of the large
denominator. UNICEF has recently prioritized its activities in
terms of equity, arguing that disproportionate health impact is
obtained from focusing interventions on the most marginalized and underprivileged communities (15). Certain countries
(e.g., Nigeria, Democratic Republic of Congo, and Pakistan)
contribute disproportionately to child and maternal mortality
because of their large size and adverse health indicators and
may merit particular attention.
In addition to finishing preexisting commitments to the
MDGs, polio eradication, and other infectious disease priorities, several urgent needs stand out. The lack of mortality surveillance in many countries prevents recognition and
description of the local impact of disease. The solution is
the development of robust vital registration systems in every
country, but until that is achievable, systems are needed to
capture data on mortality through enhanced surveillance
or surveys. Changing global trends in patterns of mortality
means that the classic indicators most widely used (child and
maternal mortality) fail to accurately describe the health situation—including the increasing proportions of deaths in young
adults and the emerging impact of noncommunicable diseases
and injuries—in many countries. Obtaining data on preventable adult mortality and its causes is a priority for surveillance
systems globally.
To address some of the challenges and assess its own performance, CDC has identified five major public health goals
for which major progress can be made with sustained, coordinated effort. These are 1) reduction of mother-to-child HIV
transmission and congenital syphilis; 2) enhanced coverage
and impact through global vaccination initiatives, including
polio; 3) elimination of lymphatic filariasis in the Americas; 4)
reduced tobacco use; and 5) decreased motor vehicle injuries.
These “winnable battles” have been named as priorities for
intervention because of the availability of practical, evidencebased strategies, and the potential for measuring progress across
a large proportion of persons at greatest risk. The timelines and
specific measurable objectives for CDC’s global winnable battles are under development. Approaches to evaluating progress
110

MMWR  /  October 7, 2011  /  Vol. 60

in these areas are under discussion, and priorities may change
over time as new challenges or opportunities arise. These topics
should not be interpreted as displacing CDC’s broad global
health portfolio, but they do represent areas for special focus.
They will be implemented as part of CDC’s comprehensive
global health framework of increasing in-country public health
capacity, health security, and health impact.
Despite predictions about global health trends, objectives set
by the MDGs, and winnable battles, predicting what issues
will preoccupy MMWR and global health 50 years from now is
risky. Further progress should be expected in the development
of diagnostics, including those used at the point of care; drugs;
and vaccines. New diseases will continue to emerge; environmental and climate change may become more prominent risk
factors for adverse outcomes; and the effect of noncommunicable diseases will continue to grow. Communications capacity
can only continue to increase, and the story of Chief Gilbert
Shamba Mayi will be less unusual.
Even as the environment changes certain constants will
remain, including the need for reliable data for public health
action, surveillance, laboratory capacity, a strong health workforce, and research. CDC will also have to evolve, yet remain
true to the core values that have guided its work over the years,
much of it described in MMWR.
Acknowledgements
The author appreciates the collaboration of Jeffrey Koplan, M.D.,
Institute for Global Health, Emory University, Atlanta, Georgia;
and Patricia Simone, M.D., Marsha Vanderford, Ph.D., and Terri
Still-LeMelle, Center for Global Health, CDC.
References
1. De Cock KM, Nasidi A, Enriquez J, et al. Epidemic yellow fever in
eastern Nigeria, 1986. Lancet 1988;331:630–3.
2. US Department of State. The First Quadrennial Diplomacy and
Development Review (QDDR): leading through civilian power. Available
at http://www.state.gov/s/dmr/qddr.
3. Koplan JP, Bond TC, Merson MH, et al. Towards a common definition
of global health. Lancet 2009;373:1993–5.
4. World Health Organization. Global Polio Eradication Initiative. Wild
poliovirus weekly update. April 6, 2011. Available at http://www.
polioeradication.org/Dataandmonitoring/Poliothisweek.aspx.
5. United Nations Secretary-General. The Millennium Development Goals
Report 2009. Available at http://www.unhcr.org/refworld/
docid/4a534f722.html.
6. World Health Organization, World Malaria Report 2010. Available at
http://www.who.int/malaria/world_malaria_report_2010/en/index.html.
7. President’s Emergency Plan for AIDS Relief, 2011. Available at http://
www.pepfar.gov/documents/organization/80161.pdf.
8. Joint United Nations Global Programme on HIV/AIDS. UNAIDS
report on the global AIDS epidemic, 2010. Available at http://www.
unaids.org/globalreport/Global_report.htm.
9. Rajaratnam JK, Marcus JR, Flaxman AD, et al. Neonatal, postneonatal,
childhood and under-5 mortality for 187 countries, 1970–2010: a
systematic analysis of progress towards Millennium Development Goal 4.
Lancet 2010;375:1988–2008.

Supplement

10. Gakidou E, Cowling K, Lozano R, et al. Increased educational attainment
and its effect on child mortality in 175 countries between 1970 and
2009: a systematic analysis. Lancet 2010;376:959–74.
11. Hogan MC, Foreman KJ, Naghavi M, et al. Maternal mortality for 181
countries, 1980–2008: a systematic analysis of progress towards
Millennium Development Goal 5. Lancet 2010;375:1609–23.
12. Rajaratnam JK, Marcus JR, Levin-Rector A, et al. Worldwide mortality
in men and women aged 15–59 years from 1970 to 2010: a systematic
analysis. Lancet 2010;375:1704–20.

13. Department of HIV/AIDS, Stop TB Department, World Health
Organization. Guidelines for intensified tuberculosis case-finding and
isoniazid preventive therapy for people living with HIV in resourceconstrained settings, 2010. Available at http://www.who.int/hiv/pub/
tb/9789241500708/en/index.html.
14. Frieden TR, Koplan JP. Stronger national public health institutes for
global health. Lancet 2010;376:1721–2.
15. United Nations Children’s Fund. Narrowing the gaps to meet the goals.
Available at http://www.unicef.org/childsurvival/files/Narrowing_the_
Gaps_to_Meet_the_Goals_090310.pdf.

MMWR  /  October 7, 2011  /  Vol. 60

111

Supplement

Advice to a Modern-Day Rip Van Winkle: Changes in State and Local
Public Health Practice During the MMWR Era at CDC
Melvin A Kohn, MD1
David W Fleming, MD2
1Public Health Division, Oregon Health Authority, Portland, Oregon
2King County Health Department, Seattle, Washington
Corresponding author: Melvin A. Kohn, MD, 800 N.E. Oregon, Suite 930, Portland, OR 97232;Telephone: 971-673-1300; Fax 971-673-1361; E-mail:
[email protected].

Imagine for a moment a dedicated but exhausted state or
local public health practitioner nodding off while reading the
volume 10, number 1, issue of MMWR in January of 1961,
only to awaken, a la Rip Van Winkle, 50 years later (1). What
would be most surprising to our time-traveling colleague
about state and local public health practice in 2011? Here is
our top 10 list.

1. There are some “old” diseases about which you
no longer have to worry much and some “new”
ones you do.
Buy yourself an up-to-date infectious disease textbook.
Vaccines have driven rates of many diseases that were common
in 1961 to very low levels today in the United States. Polio,
measles, invasive Haemophilus influenzae disease, and diphtheria are rarities, and smallpox has been eradicated (Table). In
fact, it has become a challenge to get health practitioners to
recognize these old diseases when they do occur and to mount
a rapid, competent public health response to them unless a
“senior” epidemiologist happens to be around. After your
experiences with controlling polio in the United States during
the 1950s, you might be amazed at the increasing problem of
“vaccine hesitancy” (2). The rarity of many of the old diseases
has made it difficult to convince a growing subset of parents
to vaccinate their children against them.
TABLE. Cases of selected reportable diseases — United States, 1961*
and 2008†
Reported cases by year
Disease
Poliovirus infection, all types
Measles
Invasive Haemophilus influenzae
Diphtheria

1961

2008

1,312
423,919
19,500§
617

0
140
2,886
0

* CDC. Annual supplement: reported incidence of notifiable diseases in the
United States, 1961. MMWR 1962;10(53):1–28.
† CDC. Summary of notifiable diseases—United States, 2008. MMWR 2009;
57:19–20.
§ Invasive Haemophilus influenzae cases estimated for 1985, as reported in
Bisgard KM, Kao A, Leake J et al. Haemophilusinfluenzae invasive disease in the
United States, 1994–1995: near disappearance of a vaccine-preventable childhood disease. Emerg Infect Dis 1998;4:229.Haemophilusinfluenzae was not
nationally notifiable before 1991.

112

MMWR  /  October 7, 2011  /  Vol. 60

On the treatment side, rates of tuberculosis (TB) have been
driven to historic lows, and in many jurisdictionsTB expertise
has all but disappeared. At the same time, drug treatment for
TB and many other infectious diseases has become complicated
by the continuing emergence of strains resistant to common
treatments (3).
Read that new textbook carefully because many infectious
diseases of importance today were unknown (or unrecognized)
when you fell asleep in 1961. Legionnaires disease (4), toxicshock syndrome (5), hantavirus pulmonary syndrome (6),
Lyme disease (7), cryptosporidiosis (8), norovirus infection
(9), and Escherichia coli O157:H7 infection (10) are a few
examples. Most commonly, these new illnesses were identified
as a result of outbreak investigations by CDC together with
state health departments. A key to success at characterizing and
controlling these new diseases has been an explosion of new
laboratory techniques, such as pulsed-field gel electrophoresis
and polymerase chain reaction (you may need a textbook
on infectious disease laboratory testing as well), which have
enabled more sensitive testing and more specific characterization of pathogens. The creation of national surveillance systems, such as PulseNet (11) (which allows comparison of the
molecular “fingerprints” of foodborne pathogens from across
the country), has helped in the detection of many more multistate outbreaks (and provided lots of practice on improving
cross-jurisdictional and cross-agency coordination).

2. There is a global HIV pandemic.
The first five cases of what is now called acquired immunodeficiency syndrome (AIDS) were reported in MMWR in
1981 (12). Since then, human immunodeficiency virus (HIV,
the virus that causes AIDS) has caused approximately 25 million deaths across the world, and in 2007 alone, 2.7 million
new infections occurred (13), painfully showing the limits of
traditional approaches to communicable disease control.
In 1961, control of sexually transmitted diseases focused primarily on providing health education, treatment, and contact
tracing. For HIV, the lack of a cure and a vaccine has limited
our ability to use these traditional tools. Moreover, traditional

Supplement

health education and contact tracing is more complicated and
less useful among persons at highest risk in this country—men
who have sex with men and injection drug users (drug use
became epidemic while you slept) (14,15). To implement
effective harm-reduction strategies, public health and healthcare professionals have needed to work closely with those at
highest risk and to partner with leaders and community-based
organizations from these socially marginalized communities.
This work has brought public health into the dangerous
shoals of culture wars around sexuality, homosexuality, abstinence, drug use, and personal responsibility. Today, managing
conflicts with politicians and mainstream cultural beliefs is
now part of routine work. Especially at the beginning of the
AIDS epidemic in the 1980s, the lack of empowerment and
stigmatization of homosexuals, racial and ethnic minorities,
and women were major contributors to the behaviors that
fueled the spread of HIV (16), and the emergence of HIV has
highlighted for many practitioners the link between public
health and human rights.
By providing the dispassionate imprimatur of solid science for
issues such as needle exchange (17) and HIV reporting systems
(18), CDC and MMWR have helped practitioners maintain
focus on disease prevention as the primary objective. But on
many occasions, politics have prevailed over good science,
teaching the limits of pure science-based public health practice.

3. Health care dominates the United States
economy, but many public health agencies do not
see many patients anymore.
The health-care industry accounted for 17% of the U.S. gross
national product in 2009 (19), compared with 5% in 1960
(20), and its political and financial clout today is considerable
(think military–industrial complex of your day to get an idea
of its influence). Health care is now competing—and usually
winning—against public health programs and many other
public needs for a growing slice of the government budget pie.
Since 1961, large national health insurance programs have been
implemented (called Medicare for elderly and disabled persons
and Medicaid for poor persons), although many Americans
remain uncovered. The private medical-care system also has
grown tremendously, and large for-profit health systems are
a dominant force. Prevention outside of the health-care provider’s office gets comparatively little attention or funding.
As costs have risen, health insurance financing has become
the dominant focus of public policymaking related to health.
Despite—or perhaps because of—the growth of the healthcare industry, many public health departments have stopped
providing direct clinical services. Most health departments
have few clinicians on staff (21) and limited influence over or

engagement with the inner workings of the health-care system,
except in times of large disease outbreaks, which are relatively
rare. As a consequence, the gap between health care and public
health has widened. Although most health-care providers still
look to CDC as an authoritative source of information about
health issues, and MMWR is widely respected, often the public
health system and the health-care system are on independent
tracks. Health-care providers, who should be public health’s
closest collaborators and allies, often have little interaction with
and understanding of the public health system.

4. Tobacco use in the United States peaked
in 1963.
Per capita cigarette consumption peaked in the United
States only 2 years after you read that first CDC-published
MMWR (Figure 1) (22). Although tobacco is still the leading
preventable cause of morbidity and mortality in the United
States, today only 19% of adults smoke (23). This amazing
turnaround was achieved through innovative tobacco control
and nonsmokers’ rights movements that blazed a new path for
public health practice, creating a model focused on promoting environmental and policy change, rather than providing
individual health education services. So, while in 1961 few
public health practitioners would have embraced promotion
of a tax as part of their toolbox, today promoting increases
in taxation of tobacco products has been effective and is an
evidence-based practice. And all around the country health
departments have helped pass laws to prevent exposure to
secondhand smoke (don’t even think about lighting up next
time you get in an airplane).
Experience with tobacco control also has demonstrated that
comprehensive approaches that support behavior change in a
coordinated, synergistic, and reinforcing way are needed to
effectively change a complex health behavior like smoking (24).
Increasingly the public health workforce is developing skills
related to this new paradigm. And, because most government
public health agencies are constrained in how actively they can
pursue legislative advocacy, collaboration with the nongovernment advocacy community has become increasingly important.

5. Tobacco has a serious new competitor for the
leading preventable cause of death and disability:
obesity.
While you slept, another major driver of chronic diseases
snuck up on public health. Obesity has become epidemic in
the United States, driving up rates of diabetes, heart disease,
and many other chronic health problems (Figure 2). This epidemic has been driven by changes in the ease of making poor
food choices and avoiding physical activity. Although each of
these changes was small and occurred gradually, in retrospect
MMWR  /  October 7, 2011  /  Vol. 60

113

Supplement

FIGURE 1. Chesterfield cigarette advertisement on back of 1953
Metropolitan Opera program, featuring Arthur Godfrey, popular
entertainer and smoker who later died of lung cancer.

FIGURE 2. Obesity trends* among U.S. adults — BRFSS, 1990, 1999,
2009
1990

1999

2009
Photo: CDC

their cumulative effect has been dramatic (25). For example,
concerns about safety now result in most kids being driven
rather than walking to schools. U.S. teens consume >10% of
their calories from sugar-sweetened beverages (26). And the
United States has become a nation addicted to large portions
(you will not believe how large), quick-to-prepare, inexpensive,
“fast foods.”Just as tobacco control activities brought public
health up against powerful corporate interests, similar battles
are brewing with the food industry, and conflict between health
and profit will undoubtedly continue to have a major influence
on public health practice.
An extensive research base informs tobacco control.
However, public health is still learning how to reverse the
obesity epidemic and how best to increase physical activity
and improve nutrition.

114

MMWR  /  October 7, 2011  /  Vol. 60

≥30%
25%–29%
20%–24%
15%–19%
10%–14%
<10%
No data
Abbreviation: BRFSS=Behavioral Risk Factor Surveillance System.
Source: http://www.cdc.gov/obesity/data/trends.html.
* Body mass index ≥30, or about 30 lbs. overweight for a 5’4” person.

Supplement

FIGURE 3. Oregon Public Health Agency Operations Center during
the 2009 H1N1 Influenza Pandemic.

still does not mean it is useful or even true. A 2x2 table still
can take you a long way to understanding what the data are
trying to tell you.

7. The speed and volume of information flow
have increased exponentially since 1961.

Photo: CDC

6. Everyone in the health department has a
personal computer on his or her desk.
Don’t pull out that slide rule you depended on in 1961
or, at best, you‘ll be viewed as a quaint relic of a bygone era.
Powerful computers (machines that rapidly perform calculations, among many other functions) now sit on your desk or
your lap and make possible almost instantaneous analysis of
data. And new techniques for statistical analysis, unknown in
1961, are widely used today.
These “personal computers” (PCs) also have made possible
creation of visual aids for presenting data. Color images and
photographs, as well as text and tables, can now be projected
onto large screens and easily manipulated and shared, even
to excess. Computers also can be used to design and produce
photographs and other graphics on paper. Beautiful reports
and newsletters can now easily be published from anyone’s
desk. Curiously, all of this has not improved our presentations
as much as you might predict.
Virtually all aspects of life in 2011 have been altered by
computers. However, public health practice has one additional
unique connection with PCs. One of the richest men in the
world made his fortune from creating computer programs for
these machines and then donated much of that fortune to a
foundation working to improve global health (27).
Fortunately, wisdom has not gone the way of your slide
rule. Much of what an ace epidemiologist in 1961 knew about
data remains critical today. The adage “garbage in, garbage
out” still applies, despite the newer statistical manipulations.
And, although multiple pathways to statistically significant p
values are now well within the reach of even the most junior
analysts, just because an association is statistically significant

Since 1961, an information revolution has occurred. The
widespread availability of PCs and cell phones (tiny cordless
telephones that work anywhere in the world) has made use of
e-mail and text messaging (instant electronic communication
between PCs or cell phones) and the Internet (a global, interactive storehouse of information used for almost anything you
can imagine) accessible to everyone 24/7 (24 hours a day, 7 days
a week, commonly used to describe our availability for doing
work in 2011). Not all of that information is good; practitioners today receive lots of e-mail spam (the name of the canned
meat that you ate in 1961 has been borrowed to describe
unwanted e-mails). Although these tools have increased our
connectivity with one another, they also have raised expectations for instant (yet accurate) responses. Practitioners today
spend a great deal of time answering e-mail, taking time away
from reading and face-to-face interactions, not to mention
thought, rest, and vacation.
The creation of the Internet, 24-hour television news, and
other communications channels have created an insatiable
demand for health information, and public health practitioners
are often put on the spot, expected to have that information at
their fingertips on a moment’s notice. Many are uncomfortable working with the media and ill equipped to play this new
role. Public health’s culture still values data, science, detail, and
subtlety, and that culture makes uttering sound bites (short
pithy sentences that play to the new time-compressed media)
an unnatural act.
“Social media” tools are also used by today’s public health
practitioners. These venues are evolving from moment to
moment like a Twitter message (don’t worry, most current
public health practitioners don’t really know what Twitter is
either) as new tools emerge. Practitioners today commonly
use “Google” (an “engine” for searching for information on
the Internet) and subscribe to “listservs” (computer services
that send correspondence to groups automatically). Even the
MMWR makes material available through “podcasts” (audio
recordings that can be obtained through the Internet and
loaded onto portable playback devices).

8. State and local health department employees
are increasingly virtual federal staff.
Although no constitutional amendment has yet given
the federal government primary responsibility for protecting the public’s health, Washington, D.C., rather than state
MMWR  /  October 7, 2011  /  Vol. 60

115

Supplement

government, has become the primary source of funding for
state health departments (28). Federal policymakers have
become the dominant force shaping agendas and programs.
This has its advantages. Federal funding has helped drive
adoption and standardization of science-based programs. For
example, in contrast to 1961, all states and many local jurisdictions have at least some programming in chronic disease,
primarily provided by CDC funding (29). During the past few
years, this federal funding also has partially protected state and
local health departments from state budget cuts resulting from
the worst fiscal crisis in the United States since the MMWR
began publication at CDC.
But there are downsides too. Federal funding comes most
often through categorical grants (financing for predefined
public health programs) (29). So even though we have not
become farmers, you will hear references to “program silos”
that some say inhibit leveraging of resources and creativity.
Federal priorities often displace the priorities of states and
localities, just because federal grant funds are available. In fact,
the dominance of funding for federal priorities has made it
easier for state and local elected officials, and even some health
departments, to avoid doing their own priority setting. That
lack of engagement at the state and local levels has weakened
public health practice.
Despite a great deal of federal support, substantial gaps
remain in the capacity of most health departments to address
important areas of public health practice. For example,
although injuries are the leading cause of death for persons
aged 1-44 years (30), most state and local health departments
have limited resources, if any, to address this public health
concern. Despite the great increase during the last 50 years in
public concern about environmental toxins, few environmental
public health programs at the state and local level have been
able to go very far beyond the essential services they were performing in 1961, such as restaurant inspections and oversight
of drinking water systems and sewage disposal, and include
substantial investigations of and research about exposure to
environmental toxins in their routine work.
Because of the increasing importance of federal funding in
the budgets of state and local public health agencies, federal
policy choices about the scope and role of government have
a large impact on state and local public health agencies. This
makes it especially important for the public health system to
be able to articulate what it does and demonstrate its value
in ways that are compelling for federal policy makers and the
public that elects them.

116

MMWR  /  October 7, 2011  /  Vol. 60

9. There is an Emergency Operations Center in our
basement.
Since 1961, we have gotten better at handling public health
emergencies. After the terrorist events of 2001, federal and state
governments increased attention and funding for terrorism and
emergency management. Other public health events, such as
the outbreak of severe acute respiratory syndrome (SARS) in
2003; Hurricane Katrina, which flooded New Orleans in 2005;
and 2009 pandemic influenza A (H1N1), helped focus attention on emergencies and how we handle them. Together these
crises have led to a massive federal investment in preparedness
infrastructure at state and local health departments, aiming
to fix the results of many years of neglect of buildings, data
systems, and the public health workforce.
The Incident Command System methodology has become
the standard of practice for managing public health response
in these settings (31). Health departments around the country
now routinely activate an “Emergency Operations Center” or
“EOC” (Figure 3) at the outset of an emergency to identify
and oversee the multiple independent streams of work needed
to respond competently and ensure routine and clear communications to policy makers and the public, one of the most
important elements of effective response.
The incorporation of preparedness into public health practice
has not been easy. The less hierarchic and more collaborative
culture of public health differs substantially from the more
military culture of law enforcement or emergency response, and
this cultural divide has created its own set of communication
and coordination challenges.
A lot of us have also worried about whether the new emphasis
on preparedness activities has diverted resources and distracted
attention from our most important day-to-day mission: preventing the major causes of death and disability. For example,
despite the dire consequences of the obesity epidemic, much
less funding has been made available for obesity prevention
work than for preparing for the rare possibility of a terrorism
event. On the bright side, the visibility afforded public health
in emergency situations, particularly when the public health
system is generally perceived to have performed well (as in the
2009 pandemic [H1N1] outbreak), might help the public and
policymakers better understand the relevance of public health
and build the political will to support public health system in
other areas.

Supplement

10. Our art is becoming science through research
and evidence-based practice.
Since 1961, the evidence base for public health programs
has grown, but the demand for additional evidence has only
increased. Today, to an increasing extent, funders and policymakers want to see proof of our effectiveness and are holding
us accountable for the performance of our programs. Groups
such as the Cochrane Collaboration (32) and the U.S. Task
Force on Community Preventive Services (33) have helped
apply and enhance the rigor of this technique for public health
practice and services.
When you fell asleep, public health nursing and home visiting had long been important tools in public health practice,
especially at the local level. While you slept, rigorous evaluation has demonstrated substantial impacts of home visiting by
nurses, including improved prenatal health, fewer childhood
injuries, fewer subsequent unplanned pregnancies, increased
intervals between births, increased maternal employment and
improved school readiness (34). Expansion of these programs
is likely to continue to be an important part of local public
health practice in the future.
That is just one of many areas in which rigorous research
and evaluation have confirmed and refined what state and local
public health practitioners do. The refinement and widespread
use of meta-analysis has allowed us to pool the results of
many small studies and increased the robustness and validity
of research findings in many areas. In truth, these efforts also
have highlighted the dearth of rigorous evaluation of much of
what we do in public health and the standards for acceptable
evidence of effective community-based practices are evolving. Increasingly we see the need for practice-based evidence
as well as evidence-based practice (35) to continue to hone
our work. But better science has raised expectations that our
work is evidence based and demonstrably effective. In most
settings today, personal credibility alone will not drive public
health action unless it is coupled with the accumulated and
synthesized scientific information available.

The Future
“I am your father!” cried he—“Young Rip van Winkle
once—old Rip Van Winkle now!—
Does nobody know poor Rip Van Winkle!”
—Washington Irving, Rip Van Winkle (1)
This retrospective look begs for a brief prospective glance into
the future. What if the events leading to the long sleep of our

hapless, hypothetical 1961 public health practitioner repeated
themselves and he nodded off again, only to awaken in 2061?
Prediction is a risky business. Nevertheless, we’ll go out on a
limb and venture to predict that many of the trends described
above will have continued. More old infectious diseases will
be gone or much reduced because we are likely to have highly
effective vaccines for malaria, tuberculosis, HIV, and influenza. More new diseases will be identified. The rest of the
world probably will have caught up with the developed world
in terms of the epidemiologic transition from infectious to
chronic disease. Undoubtedly spectacular new information
technologies will dramatically transform our lives. And when
we are really feeling optimistic we can even predict with some
confidence that the obesity epidemic, so long in the making,
will be well on its way to being defeated.
On the other hand, in at least three critically important areas
of public health practice 50 years from now, the outcomes
seem too close to call; the factor that determines whether we
are “alone and forgotten”—like Rip Van Winkle—may be us.

1. The need to contain health-care costs could
profoundly improve the linkage between health
care and public health. Or not.
It is frequently said these days that the rate of increase in the
costs of providing health care in the United States is unsustainable. There is less agreement on the solution. Although healthcare system improvements will be important, investments in
public health systems that support community-based programs
to address the determinants of health, improve access to quality
health care, and emphasize the delivery of preventive services
by the health-care system and at the community level also
are needed. Without those investments to address the drivers
of the need for health care, the United States will not have a
sustainable business model for its health-care system.
The current funding crisis and the potential for investments
in public health provide an opportunity for public health to
sharpen its focus on the core functions of assessment, policy
development, and assurance (36) and for the public health and
health-care systems to articulate more clearly their complementary roles and link together more closely, closing the chasm
between health care and public health and creating one system
that truly helps “assure the conditions in which people can be
healthy” (36). Electronic clinical data systems, if designed with
both clinical and state and local public health needs in mind,
will support this linkage.
But even though opportunity exists, the outcome in this area
is not assured. To reach this goal will require vision, leadership, and a new spirit of collaboration between public health
practitioners and clinicians.

MMWR  /  October 7, 2011  /  Vol. 60

117

Supplement

2. The structure of our antiquated public health
system will have changed, either because of us or
despite us.
It has been said that “if you’ve seen one health department,
you’ve seen one health department” (37) to illustrate the wide
variation in agency structure, services, budget, and political
accountability across the country. Some variation allows us to
meet different needs and take advantage of different opportunities across the country. However, in a world that is increasingly
interconnected, with instantaneous national and international
communication and concerns, the current profound differences in funding and capacity among state and local health
departments are likely to be more and more counterproductive.
The huge differences among health departments are inefficient and obstruct efforts to achieve economies of scale,
transparency, and reliable system governance. In a time when
the public demands evidence of performance and accountability from state and local health departments, these differences make it much harder to explain to the public why we do
what we do—which in turn makes advocating for resources
and political support much more difficult. New performance
standards (38) and accreditation processes (39) might help
bring data on state and local health department performance
and capacity to the surface in a standardized way that will
facilitate communication and meaningful interpretation, but
as in other areas of public health practice, data are only one
input into public health action, and the data generated by
these tools alone will not power structural changes. They are
necessary but not sufficient.
We are pretty certain that 50 years from now the structure
of the U.S. public health system will have changed profoundly.
The public’s health will benefit the most if we embrace the
need for change and lead this process rather than dig in our
heels about the status quo and allow it to be imposed on public
health from the outside.

3. Depending on how well we have addressed the
current leading causes of preventable death and
disability, government public health agencies will
either be empowered or marginalized.
Much of the increase in average life span we have enjoyed
over the past 100 years has resulted from such public health
programs as immunization, improved sanitation, and public
health services for young mothers (40). But times are changing,
and what we do every day in state and local health departments
has been slow to catch up. As rates of death and disease from
infections, as well as rates of infant and maternal mortality, fell
and rates of death from chronic disease rose, our structure and

118

MMWR  /  October 7, 2011  /  Vol. 60

programs did not evolve well in response to this epidemiologic
transition (41). Paradoxically our remarkable historical victories
place us at increasing risk for becoming victims of our own
success because we are viewed as focusing too much attention
and resources on causes of morbidity and mortality that were
dominant in past decades.
To remain relevant over the next 50 years, we will have to
better balance protecting our successes with attacking our
challenges. Preventing injury, reducing disability associated
with aging, mitigating the effects of global warming, and
preventing mental health and substance abuse problems are
just a few emerging areas in which public health could make
a big difference but currently is not doing enough. Also, the
increasing diversity of the U.S. population and the recognition of the profound influence of social determinants of health
on health outcomes demand that public health practice at all
levels develop and implement coherent and effective strategies
to tackle these foundational drivers of health. To meet the
demands in these areas at state and local health departments,
staff across the system will need to have not only subject-area
expertise but also strong skills in changing systems, environments, and policy; using media; building coalitions; and
convening and leading a broad array of partners well beyond
those of today’s public health mainstream.
In summary, the crystal ball is cloudy and public health
practice in 2061 is likely to look at least as different from
today’s practice as today’s practice looks from that of 1961.
The most profound changes are likely to be the ones that are
unimaginable today. Amidst all this uncertainty, perhaps the
safest prediction to make is that MMWR will be there to tell
us about it.
References
1. Irving W. Rip Van Winkle and other stories. New York, NY. Puffin;
1996:1–29.
2. Diekma DS, Committee on Bioethics. Responding to parental refusals
of immunization of children. Pediatrics 2005;115:1428–431.Reaffirmed
May 2009.
3. Division of Healthcare Quality Promotion, CDC. Antibiotic/
antimicrobial resistance [updated 2010 July 19. Available at http://www.
cdc.gov/drugresistance/index.html.
4. CDC. Follow-up on respiratory illness—Philadelphia. MMWR
1997;46:50–6.
5. CDC. Toxic-shock syndrome—United States. MMWR 1980;​
29:229–30.
6. CDC. Outbreak of acute illness—southwestern United States. MMWR
1993;421–4.
7. CDC. Lyme disease—United States, 1980. MMWR 1981;30:​
489–92,497.
8. MacKenzie WR, Hoxie NJ, Proctor ME, et al. A massive outbreak in
Milwaukee of Cryptosporidium infection transmitted through the public
water supply. N Engl J Med 1994;331:161–7.
9. CDC. Surveillance for foodborne disease outbreaks—United States,
2007. MMWR 2010;59:973–9.

Supplement

10. CDC. Preliminary report: foodborne outbreak of Escherichia coli
O157:H7 infections from hamburgers—western United States, 1993.
MMWR 1993;42:85–6.
11. CDC. PulseNet [updated 2009 April 28].Available at http://www.cdc.
gov/pulsenet.
12. CDC. Pneumocystis pneumonia—Los Angeles. MMWR 1981;30:250–2.
13. Joint United Nations Program on HIV/AIDS (UNAIDS). 2008 report on
the global AIDS epidemic. Geneva, Switzerland: World Health Organization;
2008. Available at http://www.unaids.org/en/KnowledgeCentre/HIVData/
GlobalReport/2008/2008_Global_report.asp.
14. National Institute on Drug Abuse International Program. Methadone
research Web guide. Available at http://www.international.drugabuse.
gov/collaboration/guide_methadone/parta_question2.html.
15. Hogben M, McNally T, McPheeters M, Hutchinson AB, Task Force on
Community Preventive Services. The effectiveness of HIV partner
counseling and referral services in increasing identification of HIVpositive individuals; a systematic review. Am J Prev Med 2007;​
33:S89–100.
16. Mahajan AP, Sayles JN, Patel VA, et al. Stigma in the HIV/AIDS
epidemic: a review of the literature and recommendations for the way
forward. AIDS.2008;22(Suppl 2):S67–79.
17. CDC. Syringe exchange programs—United States 2005. MMWR
2007;56:1164–7.
18. CDC. Guidelines for national human immunodeficiency virus case
surveillance, including monitoring for human immunodeficiency virus
infection and acquired immunodeficiency syndrome. MMWR
1999;48(No. RR-13).
19. Sisko AM, Truffler CJ, Keehan SP, Poisal JA, Clemens MK, Madison
AJ. National health spending projections: the estimated impact of reform
through 2019.Health Aff 2010:29;1933–41.
20. Levit KR, Lazenby HC, Sivarajan L. Health care spending in 1994:
slowest in decades. Health Aff 1996;15:130–44.
21. Reichart A, Lewis M.2007 State public health workforce survey results.
Washington, DC. Association of State and Territorial Health Officials.
Available at http://www.astho.org/Display/AssetDisplay.aspx?id=500.
22. CDC. Smoking and tobacco use: consumption data. Available at http://
www.cdc.gov/tobacco/data_statistics/tables/economics/consumption.
23. CDC. Vital Signs: current cigarette smoking among adults aged ≥18
years—United States, 2005–2010. MMWR 2011;60:1207–12.
24. CDC. Best practices for comprehensive tobacco control programs—2007.
Atlanta, GA: US Department of Health and Human Services, CDC,
National Center for Chronic Disease Prevention and Health Promotion,
Office on Smoking and Health; 2007.
25. Levi J, Vinter S, St. Lauren R, Segal LM.F as in fat: how obesity threatens
America’s future. Washington, DC: Trust for America’s Health; 2010.
Available at http://healthyamericans.org/reports/obesity2010/
Obesity2010Report.pdf.

26. Jacobson MF. Liquid candy: how soft drinks are harming America’s
health. Washington, DC: Center for Science in the Public Interest.
Available at http://www.cspinet.org/new/pdf/liquid_candy_final_w_
new_supplement.pdf.
27. Bill and Melinda Gates Foundation. Global Health Program. Available
at http://www.gatesfoundation.org/global-health/Pages/overview.aspx.
28. Association of State and Territorial Health Officials. Profile of state
public health, volume 1.Washington, DC. Association of State and
Territorial Health Officials; 2007: 46.Available at http://www.astho.org/
Display/AssetDisplay.aspx?id=2882.
29. CDC. Grant funding profiles [updated 2010 September 15]. Available
at http://www.cdc.gov/fundingprofiles/.
30. CDC. 10 leading causes of death by age group, United States—2007.
Available at http://www.cdc.gov/injury/wisqars/pdf/Death_by_
Age_2007-a.pdf.
31. CDC. Emergency Operations Center (EOC) [updated 2010 July 19].
Available at http://emergency.cdc.gov/cdcpreparedness/eoc.
32. The Cochrane Collaboration. Available at http://www.cochrane.org.
33. The Task Force on Community Preventive Services [updated July 26,
2010].Available at http://www.thecommunityguide.org/about/taskforce-members.html.
34. American Academy of Pediatrics, Council on Child and Adolescent
Health. The Role of Home-Visitation Programs in Improving Health
Outcomes for Children and Families. Pediatrics. 1998;3:486-9.
35. Green LW, Glasgow RE. Evaluation the relevance, generalization, and
applicability of research: issues in external validation and translation
methodology. Eval Health Prof 2006;29:126–53.
36. Committee for the Study of the Future of Public Health, Institute of
Medicine. The future of public health. Washington, DC: National
Academy Press; 1988:7–8.
37. Menkens AJ, Stone D, Wood BW. Local public health department
accreditation: thoughts from North Carolina. J Public Health Manag
Pract 2009;15:443–5.
38. Division of Public Health Performance Improvement (DPHPI) [updated
2009 July 31].Available at http://www.cdc.gov/ostlts/about/DPHPI.html.
39. Public Health Accreditation Board. Available at http://www.phaboard.org.
40. CDC. Ten great public health achievements—United States, 1900–1999.
MMWR 1999;48:241–3.
41. Frieden TR. Asleep at the switch; local public health and chronic disease.
Am J Public Health 2004;94:2059–61.

MMWR  /  October 7, 2011  /  Vol. 60

119

Supplement

On the front cover: The MMWR front pages presented on the cover represent the evolution in the format of MMWR during its 50-year history
at CDC.

MMWR, January 13, 1961
Influenza table
MMWR, August 27, 2010
MMWR, January 11, 2002
MMWR, January 15, 1993

Epidemic Intelligence
Service (EIS) logo

MMWR, July 8, 2011

MMWR, January 15, 1999

Influenza chart
MMWR, February 18, 2011

Flour Fortification
Initiative map
MMWR, August 13, 2010

120

MMWR  /  October 7, 2011  /  Vol. 60

Supplement

The Morbidity and Mortality Weekly Report (MMWR) Series is prepared by the Centers for Disease Control and Prevention (CDC) and is available free of
charge in electronic format. To receive an electronic copy each week, visit MMWR’s free subscription page at http://www.cdc.gov/mmwr/mmwrsubscribe.
html. Paper copy subscriptions are available through the Superintendent of Documents, U.S. Government Printing Office, Washington, DC 20402;
telephone 202-512-1800.
Address all inquiries about the MMWR Series, including material to be considered for publication, to Editor, MMWR Series, Mailstop E-90, CDC, 1600
Clifton Rd., N.E., Atlanta, GA 30333 or to [email protected].
All material in the MMWR Series is in the public domain and may be used and reprinted without permission; citation as to source, however, is appreciated.
Use of trade names and commercial sources is for identification only and does not imply endorsement by the U.S. Department of Health and Human Services.
References to non-CDC sites on the Internet are provided as a service to MMWR readers and do not constitute or imply endorsement of these organizations or their programs by CDC or the U.S. Department of Health and Human Services. CDC is not responsible for the content of these sites. URL
addresses listed in MMWR were current as of the date of publication.

U.S. Government Printing Office: 2011-723-011/21081 Region IV  ISSN: 1546-0738