National Notifiable Infectious Diseases and Conditions

Notice To Data Users
2021 Weekly Data
Notices
February 2021 Due to data processing issues at CDC, data for the following jurisdictions may be incomplete for week 7: Alaska, Arizona, California, Connecticut, Delaware, Florida, Hawaii, Louisiana, Maryland, Michigan, Missouri, North Dakota, New Hampshire, New York City, Oregon, Pennsylvania, and Rhode Island.
January 2021 In 2020, the Council of State and Territorial Epidemiologists (CSTE) approved the addition of coronavirus disease 2019 (COVID-19) to the list of nationally notifiable conditions. Data for COVID-19 are not currently published in either the 2020 or the 2021 weekly NNDSS tables, but instead are accessible here: https://www.cdc.gov/coronavirus/2019-ncov/cases-in-us.html. CSTE adopted the first COVID-19 national surveillance case definition on April 5, 2020, and they approved a revision to the COVID-19 national surveillance case definition, effective August 5, 2020.
Errata
February 2021 In Table 1n of the 2021 NNDSS weekly tables for week 1 only, data for Haemophilus influenzae in children < 5 years categorized as "non-b serotype" and "unknown serotype" were updated on 02/26/2021 to correct the data associated with these two serotype categories. The original version of the tables incorrectly displayed data for "non-b serotype" in the "unknown serotype" column and incorrectly displayed data for "unknown serotype" in the "non-b serotype" column. The data are corrected now.
2020 Weekly Data
Notices
September 2020 Tuberculosis data included in the 2020 weekly NNDSS Table 1jj for weeks 4-31 are incorrect for New York City; the Middle Atlantic region total; U.S. Residents, excluding U.S. Territories total; and the grand total, due to data processing issues.
September 2020 Tuberculosis data included in the 2020 weekly NNDSS Table 1jj for weeks 32-33 are incorrect for the U.S. Residents, excluding U.S. Territories total and the grand total, due to data processing issues.
August 2020 Data for all diseases and conditions from Texas for 2019 and 2020 published in the 2020 week 32 NNDSS tables are incomplete, except for the arboviral diseases, congenital syphilis, and tuberculosis, due to a data processing issue at CDC.
August 2020 Data from California, published in the 2020 weekly NNDSS tables for week 29 for years 2019 and 2020, were incomplete when originally published on July 24, 2020. On August 4, 2020, incomplete case counts were replaced with a "U" indicating case counts are not available for specified time periods. This change impacted data for the following conditions and tables:
  • campylobacteriosis (table 1f)
  • carbapenemase-producing carbapenem-resistant Enterobacteriaceae, chancroid, and Chlamydia trachomatis infection (table 1g)
  • coccidioidomycosis (table 1h)
  • gonorrhea and Haemophilus influenzae invasive disease (table 1m)
  • Haemophilus influenzae invasive disease (table 1n)
  • hepatitis A acute and hepatitis B acute (table 1p)
  • hepatitis C acute (table 1q)
  • hepatitis C perinatal infection (table 1r)
  • listeriosis (table 1u)
  • measles (table 1v)
  • meningococcal disease (tables 1w and 1x)
  • mumps (table 1y)
  • pertussis (table 1z)
  • shigellosis (table 1ff)
  • syphilis congenital and syphilis primary and secondary (table 1hh)
January 2020 Beginning in 2020, tuberculosis data will appear in the weekly NNDSS tables. Spotted fever rickettsiosis will no longer appear in the weekly NNDSS tables, however it will continue to be published in the annual NNDSS tables. The Council of State and Territorial Epidemiologists approved new surveillance case definitions for the following nationally notifiable infectious diseases: acute hepatitis C, chronic hepatitis C, pertussis, plague, legionellosis, and spotted fever rickettsiosis. These case definitions will be applied to new cases in surveillance year 2020. There were no new nationally notifiable conditions added to the NNDSS, as a result of approved 2019 CSTE position statements.
Errata
February 2021 In Table 1n of the 2020 NNDSS weekly tables for weeks 1-53, data for Haemophilus influenzae in children < 5 years categorized as "non-b serotype" and "unknown serotype" were updated on 02/26/2021 to correct the data associated with these two serotype categories. The original version of the tables incorrectly displayed data for "non-b serotype" in the "unknown serotype" column and incorrectly displayed data for "unknown serotype" in the "non-b serotype" column. The data are corrected now.
February 2020 Measles data for weeks 1-4 (in Table 1v) were updated on 02-28-2020 to correct the classification of imported and indigenous. Measles is considered imported if the disease was acquired outside of the United States and is considered indigenous if the disease was acquired anywhere within the United States or it is not known where the disease was acquired.
2019 Weekly Data
Notices
January 2019 The following changes were made to the weekly 2019 tables of nationally notifiable infectious diseases and conditions:
  • The previous Table 1 format (which displayed infrequently reported notifiable diseases) was retired and data for all conditions in that table (except for diphtheria) are displayed using the weekly Table 2 format. Table 2 was renamed to Table 1.
  • The 2019 NNDSS data in the new Table 1 are stratified by U.S. Residents, excluding U.S. Territories; U.S. Territories; and non-U.S. Residents; based upon the reported 'country of usual residence' for the case. This stratification is not applied to the 2018 NNDSS data in the 2019 table.
  • The previous 52 week median statistic is no longer displayed, but the previous 52 week maximum and cumulative year-to-date counts are retained.
  • Changes to the new Table 1 as a result of approved 2018 Council of State and Territorial Epidemiologists position statements include the following:
    • 'Candida auris, clinical cases' was added as a new nationally notifiable disease.
    • Salmonella Paratyphi infection and Salmonella Typhi infection replaced Paratyphoid fever and Typhoid fever, respectively.
    • Salmonellosis (excluding S. Typhi infection and S. Paratyphi infection) replaced Salmonellosis (excluding paratyphoid fever and typhoid fever).
    • Carbapenemase-producing carbapenem-resistant Enterobacteriaceae (CP-CRE) represents a consolidation of CP-CRE species Klebsiella spp, CP-CRE E. coli, and CP-CRE Enterobacter spp.
  • The quarterly Tuberculosis Table 3 was renamed Table 2.
Figure 1 only includes data among U.S. residents (and therefore excludes data among U.S. Territories and non-U.S. residents).
October 2019 In 2019, CDC undertook a critical review of the content and method used to create Figure 1. Input from jurisdictions through the Council of State and Territorial Epidemiologists (CSTE) and from CDC programs was sought to determine usefulness and desire to maintain the figure. A determination was made that due to the limited usefulness of Figure 1, it will no longer be published as of the first week in surveillance year 2020.
November 2019 Software data processing failures resulted in incomplete weekly case counts for all 2019 tables for weeks 42 through 46.
November 2019 Software data processing failures resulted in incomplete weekly case counts in Tables 1a - 1pp and in Figure 1 for weeks 42 through 46 of the 2019 data.
December 2019 Starting week 1 of 2020, tuberculosis data will be presented in Table 1 and Table 2 will be discontinued.
March 2020 Measles 2019 data in Table 1v for weeks 1-51 were was updated to remove the stratification of cases by imported and indigenous case classification status. Please see week 52, 2019 data for measles cases stratified by imported and indigenous status.
Errata
February 2020 Measles data for week 52 of the 2019 data (Table 1v) were updated on 02-28-2020 to correct the classification of imported and indigenous. Measles is considered imported if the disease was acquired outside of the United States and is considered indigenous if the disease was acquired anywhere within the United States or it is not known where the disease was acquired.
2018 Weekly Data
Notices
January 2018 Beginning with the 2018 NNDSS data, there are a number of changes to the NNDSS display of weekly data.
  • Non-congenital Zika virus disease was removed from Table I and added to Table 2.
  • Paratyphoid fever was added to Table 1. Prior to 2018, cases of paratyphoid fever were included with salmonellosis cases in Table 2.
  • With the removal of paratyphoid fever cases from the salmonellosis case counts in 2018, salmonellosis was replaced with "salmonellosis (excluding paratyphoid fever and typhoid fever)" in Table 2. To obtain data that are comparable to previous years (2017 and earlier), you will need to sum the paratyphoid case count with the "salmonellosis (excluding paratyphoid fever and typhoid fever)" cases count.
  • Carbapenemase Producing Carbapenem-Resistant Enterobacteriaceae (CP-CRE), due to Klebsiella spp, Escherichia coli, and Enterobacter spp. were added to Table 2.
Errata
February 2019 Weeks 1-52 data for Haemophilus influenzae, invasive disease in Table 1 of the 2018 data were updated on Monday, February 11, 2019. Labels for "Nontypeable" and "Non-b serotype" were incorrectly placed resulting in the numbers being switched for these two rows. They are now correct.
Page last reviewed: March 01, 2021
Content source: CDC WONDER