About Annual Tables (Final)

Annual data are considered finalized data. Finalized data are created within approximately 6 months after the end of the calendar year. CDC finalizes NNDSS data in collaboration with the state and territorial health department data providers and the relevant CDC program for each notifiable disease and condition. Finalized counts by condition and reporting jurisdiction are published by CDC after each state and territorial health departments verify the finalized data. The NNDSS surveillance data likely represent an underestimate of the true number of cases of a given condition because of under-recognition and under-reporting of disease.

Incidence was calculated as the number of reported cases for each infectious disease or condition divided by either the U.S. resident population for the specified demographic population or the total U.S. resident population, multiplied by 100,000. For territories, incidence in this summary was calculated as the number of reported cases for each infectious disease or condition divided by either the territorial resident population for the specified demographic population or the total territorial resident population, multiplied by 100,000. When a national notifiable infectious disease or condition was associated with a specific restriction (such as age, sex, race, ethnicity), the same restriction was applied to the population in the denominator of the incidence calculation. In addition, population data from states in which the disease or condition was not reportable or was not available are excluded from incidence calculations. Unless otherwise stated, disease totals for the United States do not include data for American Samoa, Guam, Puerto Rico, the Commonwealth of the Northern Mariana Islands, or the U.S. Virgin Islands. Unless otherwise stated, disease totals for the United States do not include data for American Samoa, Guam, Puerto Rico, the Commonwealth of the Northern Mariana Islands, or the U.S. Virgin Islands.

For a report of a national notifiable disease or condition to be published by the NNDSS, the reporting state or territory must have designated the infectious disease or condition reportable in their state or territory for the year corresponding to the year of report to CDC. After this criterion is met, the infectious disease- or condition-specific publication criteria below are applied. (Beginning with data year 2016, publication criteria are published with the data tables on CDC WONDER.) When “all reports” is listed for the publication criteria, this means that cases designated with unknown or suspect case confirmation status will be included in the counts along with probable and confirmed cases. Data for new nationally notifiable infectious diseases or conditions are not usually available from reporting jurisdictions until January of the year following the approval of the CSTE position statement. In addition, CDC must have Office of Management and Budget Paperwork Reduction Act approval to request data from reporting jurisdictions (). As a result, there is usually a delay between the time that CSTE recommends a condition be made nationally notifiable and the time CDC can aggregate the data submitted by reporting jurisdictions.

Only data from reporting states, territories, and jurisdictions that designated the infectious disease or condition as reportable are included in the finalized tables.

References

  1. U.S. Department of Health and Human Services. Information Collection and Paperwork Reduction Act (PRA) overview. Washington, DC: U.S. Department of Health and Human Services; 2015. https://www.usability.gov/how-to-and-tools/guidance/pra-overview.htmlexternal icon
Page last reviewed: April 16, 2021