What to know
- NORS data are available online in BEAM Dashboard, an interactive data tool from CDC, and for download at data.cdc.gov.
- Read on for guidance on accessing, using, and analyzing these data.
Outbreak data at your fingertips
BEAM Dashboard
The Bacteria, Enterics, Amoeba, and Mycotics (BEAM) Dashboard is an interactive tool to access and visualize data from the National Outbreak Reporting System (NORS).
Use BEAM Dashboard's "NORS View" to search and access data from reports of foodborne and waterborne disease outbreaks and enteric (intestinal) disease outbreaks spread by contact with environmental sources, infected people or animals, and other means.
Data sets (data.cdc.gov)
Download a streamlined NORS data set that includes information on pathogens, outbreak settings, implicated foods and water sources, and more.
More information
Using NORS Data
Most outbreaks in the United States are investigated by state, local, and territorial health departments. Outbreak information is then voluntarily reported to CDC by the public health agency that conducted the investigation. CDC may assist with outbreak investigations that involve more than one state, outbreaks that are particularly large, or for which the state or local health department requests assistance. The current reporting forms can be found on Reporting Guidance and Training.
Foodborne and waterborne disease outbreaks have been reported to CDC since the 1970s. Reporting was expanded in 2009 to include all enteric disease outbreaks, regardless of mode of transmission, and in 2023 to include reporting of certain fungal disease outbreaks.
CDC epidemiologists routinely perform data quality and assurance procedures before summarizing and publishing data. This process is referred to as "close-out." Final data are typically available for release 12–18 months after the end of the reporting year; this allows states time to finalize reports and CDC time to perform close-out. NORS is a dynamic system, and reports can be modified when new information is available, even months or years after data have been closed out.
An outbreak reported to NORS is defined as the occurrence of two or more cases of a similar illness resulting from a common exposure. Data on specific reports might not be released if
- the report does not meet the definition of an outbreak (e.g., only contains information on a single case of illness), or
- the report has not been finalized by the state that reported it or has not been closed-out by CDC.
- Reporting of outbreaks to CDC is voluntary. Outbreaks are likely underreported, which might vary by outbreak mode of transmission because of limited resources and training in health departments.
- Only a small proportion of illnesses reported are identified as associated with outbreaks. The extent to which the distribution of various sources and settings implicated in outbreaks reflects the same sources of infection and settings of sporadic illnesses is unknown.
- Outbreaks occurring on cruise ships with international ports of call and those where the exposure occurred outside the United States are not reported through NORS. For more information on cruise ship outbreaks, please visit the CDC's Vessel Sanitation Program.
- Additional limitations may apply to the content or use of outbreak surveillance datasets.
- NORS Relational Data Dictionary (updated January 2023): A complete list of variables contained in the CDC 52.14 form and downloadable by NORS users in a relational format
- NORS Flat Data Dictionary (updated January 2023): A complete list of variables contained in the CDC 52.14 form and downloadable by NORS users in a flat format