PRA Burden Statement Provided on the NNDSS Data Collection and Reporting Webpage

What is Case Surveillance?
Related Pages
Case surveillance is foundational to public health practice. It helps us to understand diseases and their spread
and determine appropriate actions to control outbreaks. Case surveillance occurs each time public health
agencies at the local, state, or national levels collect information about a case or person diagnosed with a
disease or condition that poses a serious health threat to Americans. These diseases and conditions include
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infectious diseases, such as coronavirus disease 2019 (COVID-19);
foodborne outbreaks, such as E.coli; and
noninfectious conditions, such as lead poisoning.

View or Download Our Materials
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Infographic PDF [341 KB, 2 Pages, 508]
Overview Fact Sheet [162 KB, 2 Pages, 508]
Overview Video (YouTube)

Case surveillance starts at local, state, and territorial public health departments. Local laws and regulations
specify which diseases and conditions must be reported. The health departments work with healthcare
providers, laboratories, hospitals, and other partners to get the information needed to monitor, control, and
prevent these reportable diseases and conditions in their communities.
Health departments also notify CDC about certain conditions so we can track them for the whole country. CDC
monitors about 120 of these notifiable diseases and conditions at the national level. This important step helps
protect the health of individual communities and the nation. Following standard case definitions, case
surveillance captures information that public health officials can use to understand where diseases are
occurring, how they can be prevented, and which groups are most heavily impacted. This information includes:
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who is affected—the demographic, clinical, and epidemiologic characteristics;
where they are affected—the geographic distribution of disease; and
how they are affected—the course of clinical illness and care received.

Reportable or Notifiable: What’s the Difference?
Reportable or Notifiable: What’s the Difference?
Reportable Diseases and Conditions
• Each

state or territory sets local laws and rules
for which diseases and conditions must be
reported.

Notifiable Diseases and Conditions
• The Council

of State and Territorial
Epidemiologists and CDC identify the list of
notifiable diseases and conditions.

Reportable or Notifiable: What’s the Difference?
Reportable Diseases and Conditions

Notifiable Diseases and Conditions

• Healthcare professionals,

• States

• Public health

• Case records

• This

• CDC

• The list

• The list

laboratories,
hospitals, and other providers must tell
public health departments when a person is
diagnosed.
departments collect information
about the person and how they became ill.
information is used to locate the source of
an outbreak and prevent spread.

of diseases and conditions can change
every year.

voluntarily inform CDC when a person
meets certain criteria to become a case.*

do not contain personally
identifiable information.
uses data to monitor, measure, and alert
individual communities or the nation to
outbreaks and other public health threats.
of about 120 diseases and conditions is
updated every year.

About the National Notifiable Diseases Surveillance System
CDC conducts case surveillance through the National Notifiable Diseases Surveillance System (NNDSS). In the
case surveillance process, about 3,000 health departments gather and use data on disease cases to protect their
local communities. Through NNDSS, CDC receives and uses these data to keep people healthy and defend
America from health threats.
CDC programs responsible for national surveillance, prevention, and control of infectious and noninfectious
conditions are found in the following centers:
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Center for Global Health (CGH);
National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP);
National Center for Emerging and Zoonotic Infectious Diseases (NCEZID);
National Center for Environmental Health (NCEH);
National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention (NCHHSTP);
National Center for Immunization and Respiratory Diseases (NCIRD); and
National Institute for Occupational Safety and Health (NIOSH).

These programs collaborate with the Council of State and Territorial Epidemiologists to determine which
conditions reported to local, state, and territorial public health departments are nationally notifiable. The
Council of State and Territorial Epidemiologists brings together disease and surveillance experts at CDC and in
the health departments to determine what types of data should be included in national notifications.
NNDSS receives, processes, and provides data on national notifiable diseases to programs across CDC. The
programs use these data to do the following:
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recognize disease outbreaks;
track the spread of disease at the state, regional, and national levels;

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identify geographic areas of concern and inform state decision makers;
help state and local public health departments better control disease by identifying groups most at risk;
and
evaluate and fund disease control activities.

By the Numbers
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About 120 diseases are under surveillance through NNDSS, including infectious diseases, bioterrorism
agents, sexually transmitted diseases, and noninfectious conditions.
Nearly 2.7 million disease cases are reported through NNDSS each year.
About 3,000 public health departments send disease data to 60 state, territorial, and other public
health departments, who then send the data to CDC.
100% of the American population is protected through NNDSS.

NNDSS Modernization
As technology, data, and exchange standards evolve, CDC is strengthening and modernizing the infrastructure
that supports NNDSS. As part of the Data Modernization Initiative, CDC is enhancing the ability of NNDSS to
provide comprehensive, timely, and high-quality data for public health decision making. Through this multiyear initiative, CDC is making the NNDSS technological infrastructure more robust so that it is based on
interoperable, standardized data and exchange mechanisms.

More About Case Surveillance and NNDSS

How We Conduct Case-Based Disease Surveillance
Learn about the process and data systems that NNDSS uses to collect national notifiable disease case data.
Read More

History and Modernization of Case Surveillance
View major milestones in the advancement of notifiable disease case surveillance.
Read More
* OMB No. 0920-0728 (Expiration Date: 07/31/2025) The public reporting burden of this collection of information is estimated to
average 20 minutes per response for states, cities, and territories that automate case notification, 2 hours for states and cities that do
not automate, and 20 minutes for territories and freely associated states that do not automate. This includes the time for reviewing
instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection
of information. An agency may not conduct or sponsor, and a person is not required to respond to all collection of information unless
it displays a currently valid OMB control number. Send comments regarding this burden estimate or any other aspect of this collection
of information, including suggestions for reducing this burden to – CDC/ATSDR Reports Clearance Officer; 1600 Clifton Road NE,
MS D-74, Atlanta, Georgia 30329 ATTN: PRA (0920-0728).

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Last Reviewed: July 20, 2022
Source: Division of Health Informatics and Surveillance
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