Nationally Notifiable Infectious Diseases and Conditions, United States: Annual Tables

TABLE 1. Annual reported cases of notifiable diseases and rates* per 100,000, United States, excluding U.S. Territories and Non-U.S. Residents, 2020
Data from some reporting areas may be incomplete due to the coronavirus disease 2019 (COVID-19) pandemic or due to post-reconciliation data updates that could not be confirmed or included in the final data set. Please see Note #9 and Note #10, respectively.
Disease Case Count Rate
Anthrax 1 0.00
Arboviral diseases
Chikungunya virus disease 37 0.01
Eastern equine encephalitis virus disease
Neuroinvasive 13 0.00
Non-neuroinvasive — —
Jamestown Canyon virus disease
Neuroinvasive 10 0.00
Non-neuroinvasive 3 0.00
La Crosse virus disease
Neuroinvasive 84 0.03
Non-neuroinvasive 4 0.00
Powassan virus disease
Neuroinvasive 19 0.01
Non-neuroinvasive 1 0.00
St. Louis encephalitis virus disease
Neuroinvasive 14 0.00
Non-neuroinvasive 2 0.00
West Nile virus disease
Neuroinvasive 558 0.17
Non-neuroinvasive 172 0.05
Western equine encephalitis virus disease
Neuroinvasive — —
Non-neuroinvasive — —
Babesiosis
Total 1,820 0.64
Confirmed 1,631 0.57
Probable 189 0.07
Botulism
Total 189 0.06
Foodborne 8 0.00
Infant 146 3.91
Other (wound & unspecified) 35 0.01
Brucellosis 87 0.03
Campylobacteriosis 51,764 15.71
Candida auris, clinical † 255 0.08
Carbapenemase-producing carbapenem-resistant Enterobacteriaceae 1,848 0.61
Chancroid — —
Chlamydia trachomatis infection 1,579,837 479.49
Cholera 1 0.00
Coccidioidomycosis 19,220 13.70
Coronavirus Disease 2019 (COVID-19)
Total 21,149,731 6,419.04
Confirmed 19,179,356 5,821.03
Probable § 1,970,375 598.02
Cryptosporidiosis
Total 7,648 2.32
Confirmed 5,861 1.78
Probable 1,787 0.54
Cyclosporiasis 2,689 0.90
Dengue virus infections 
Dengue 441 0.13
Dengue-like illness 9 0.00
Severe dengue — —
Diphtheria 1 0.00
Ehrlichiosis and Anaplasmosis
Anaplasma phagocytophilum infection 3,637 1.15
Ehrlichia chaffeensis infection 1,178 0.37
Ehrlichia ewingii infection 21 0.01
Undetermined ehrlichiosis/anaplasmosis 50 0.02
Giardiasis 9,453 3.66
Gonorrhea 677,751 205.70
Haemophilus influenzae, invasive disease
All ages, all serotypes 2,996 0.91
Age <5 years
Serotype b 15 0.08
Non-b serotype 76 0.39
Nontypeable 104 0.54
Unknown serotype 121 0.04
Hansen's disease 68 0.02
Hantavirus infection, non-hantavirus pulmonary syndrome ** 2 0.00
Hantavirus pulmonary syndrome 14 0.00
Hemolytic uremic syndrome post-diarrheal 167 0.05
Hepatitis, Viral Disease ††
Hepatitis A 9,946 3.02
Hepatitis B
Acute 2,155 0.66
Perinatal infection 10 0.13
Hepatitis C
Acute 6,025 1.89
Confirmed 4,798 1.50
Probable 1,227 0.38
Perinatal infection 165 1.62
Human immunodeficiency virus diagnoses 25,007 7.59
Influenza-associated pediatric mortality 171 0.23
Invasive pneumococcal disease §§
All ages 11,946 4.86
Confirmed 11,718 4.76
Probable 228 0.09
Age <5 years 561 0.21
Confirmed 536 3.45
Probable 25 0.16
Legionellosis ¶¶ 6,310 1.92
Leptospirosis 51 0.02
Listeriosis ***
Total 780 0.24
Confirmed 754 0.23
Probable 26 0.01
Lyme disease
Total 18,000 5.49
Confirmed 12,123 3.70
Probable 5,877 1.79
Malaria 603 0.18
Measles †††
Total 12 0.00
Indigenous 6 0.00
Imported 6 0.00
Meningococcal disease
All serogroups 242 0.07
Serogroups ACWY 80 0.02
Serogroup B 40 0.01
Other serogroups 16 0.00
Unknown serogroup 106 0.03
Mumps 694 0.21
Novel Influenza A virus infections — —
Pertussis 6,124 1.86
Plague §§§ 9 0.00
Poliomyelitis, paralytic — —
Poliovirus infection, nonparalytic — —
Psittacosis 8 0.00
Q fever
Total 120 0.04
Acute 90 0.03
Chronic 30 0.01
Rabies
Animal 4,457 1.35
Human — —
Rubella 6 0.00
Rubella, congenital syndrome — —
Salmonella Paratyphi infection ¶¶¶ 75 0.02
Salmonella Typhi infection **** 182 0.06
Salmonellosis (excluding S. Typhi infection and S. Paratyphi infection) †††† 45,442 13.79
Severe acute respiratory syndrome-associated coronavirus disease — —
Shiga toxin-producing Escherichia coli (STEC) 9,922 3.01
Shigellosis 9,108 2.76
Smallpox — —
Spotted fever rickettsiosis
Total 1,175 0.36
Confirmed 64 0.02
Probable 1,111 0.34
Streptococcal toxic shock syndrome 224 0.11
Syphilis
Total, all stages §§§§ 133,933 40.65
Congenital ¶¶¶¶ 2,148 55.88
Primary and secondary 41,654 12.64
Tetanus 17 0.01
Toxic shock syndrome (other than Streptococcal) 24 0.01
Trichinellosis — —
Tuberculosis 7,174 2.18
Tularemia 150 0.05
Vancomycin-intermediate Staphylococcus aureus 45 0.02
Vancomycin-resistant Staphylococcus aureus ***** 1 0.00
Varicella morbidity 2,927 1.05
Varicella mortality 1 0.00
Vibriosis
Total 1,852 0.57
Confirmed 1,133 0.35
Probable 719 0.22
Viral hemorrhagic fevers
Crimean-Congo hemorrhagic fever virus — —
Ebola virus — —
Guanarito virus — —
Junin virus — —
Lassa virus — —
Lujo virus — —
Machupo virus — —
Marburg virus — —
Sabia virus — —
Yellow fever — —
Zika virus
Zika virus disease, congenital ††††† — —
Zika virus disease, non-congenital 4 0.00
Zika virus infection, congenital ††††† — —
Zika virus infection, non-congenital 19 0.01
  • —: No reported cases — The reporting jurisdiction did not submit any cases to CDC.
  • * For population data, see Table 8. Also see Notes #3 and #7.
  • † Candida auris colonization/screening cases are not included in this table. These data are available on the Mycotic Diseases Branch's Tracking Candida auris page (https://www.cdc.gov/fungal/candida-auris/tracking-c-auris.html)
  • § Please see Note #11.
  • ¶ Counts include confirmed and probable dengue cases.
  • ** Case counts may include Old World hantavirus infections, such as Seoul virus.
  • †† Chronic hepatitis B and chronic hepatitis C data are not included in NNDSS tables but reported case counts are included in the annual Viral Hepatitis Surveillance Report, 2020, published online by CDC's Division of Viral Hepatitis, available at https://www.cdc.gov/hepatitis/statistics/SurveillanceRpts.htm.
  • §§ Counts include drug resistant and susceptible cases of Invasive Pneumococcal Disease. This condition was previously named Streptococcus pneumoniae invasive disease and cases were reported to CDC using different event codes to specify whether the cases were drug resistant or in a defined age group, such as <5 years.
  • ¶¶ In 2020, the CSTE case definition changed such that cases diagnosed by PCR were classified as confirmed, whereas previously those cases were classified as suspect and did not meet the publication/print criteria.
  • *** Before 2019, probable cases were not reported, and cases in neonates ≤60 days of age were counted as one case in a mother-infant pair. Beginning in 2019, confirmed and probable cases are being reported, and maternal and neonatal cases are being counted separately.
  • ††† 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.
  • §§§ Beginning in 2020, confirmed and probable plague cases are being combined and published. In 2019, only confirmed plague cases were published.
  • ¶¶¶ Beginning in January 2019, cases began to be reported as Salmonella Paratyphi infection. In 2018, cases were reported as paratyphoid fever. Prior to 2018, cases of paratyphoid fever were considered salmonellosis.
  • **** Beginning in January 2019, cases began to be reported as Salmonella Typhi infection. In previous years, cases were reported as typhoid fever.
  • †††† Beginning in January 2019, cases began to be reported as salmonellosis (excluding Salmonella Typhi infection and Salmonella Paratyphi infection). In 2018, cases were reported as salmonellosis (excluding paratyphoid fever and typhoid fever). Prior to 2018, cases of paratyphoid fever were considered salmonellosis.
  • §§§§ Includes the following categories: primary; secondary; early non-primary non-secondary (includes cases previously reported as early latent); unknown duration or late (includes cases previously reported as late latent syphilis and cases previously reported as late syphilis with clinical manifestations) and congenital syphilis.
  • ¶¶¶¶ Congenital syphilis cases are usually assigned to the mother's state of residence at the time of delivery. Data for congenital syphilis are aggregated by the infant's year of birth.
  • ***** Vancomycin-resistant Staphylococcus aureus cases reported in this table may not have been verified by CDC. CDC verified 0 vancomycin-resistant Staphylococcus aureus cases in 2020.
  • ††††† Data reported to ArboNET using the national surveillance case definition for congenital Zika virus infection (CSTE Position Statement 16-ID-01).
Notes:
  1. These are annual cases of selected infectious national notifiable diseases from the National Notifiable Diseases Surveillance System (NNDSS). NNDSS data reported by the 50 states, New York City, the District of Columbia, and the U.S. territories are collated and published. Cases are reported by state health departments to CDC weekly. Because source datasets may be updated as additional information is received, statistics in publications based on that source data may differ from what is presented in these tables. Source datasets for the 2020 annual tables were officially closed on September 27, 2022.
  2. The list of national notifiable Infectious diseases and conditions for 2020 and their national surveillance case definitions are available by navigating to the Surveillance Case Definitions | CDC web page, selecting "2020" for the notifiable condition list year, checking "Infectious" conditions, and clicking "Get Notifiable List by Year". This list incorporates the Council of State and Territorial Epidemiologists (CSTE) position statements approved in 2019 by CSTE for national surveillance that were implemented in January 2020. Revised case definitions were implemented for the following conditions: plague, legionellosis, acute hepatitis C, spotted fever rickettsiosis, and pertussis. In addition, CSTE adopted the first coronavirus disease 2019 (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. Publication criteria for the finalized 2020 data are available at https://wonder.cdc.gov/nndss/documents/2020_NNDSS_Publication_Criteria_03162022.pdf. See also Guide to Interpreting Provisional and Finalized NNDSS Data.
  3. Population estimates for incidence rates are July 1st, 2020, estimates obtained from the National Center for Health Statistics (NCHS) postcensal estimates of the resident population of the United States for April 1, 2010, to July 1, 2020, by year, county, single year of age (range: 0 to 85 years), bridged-race (white, black or African American, American Indian or Alaska Native, Asian, or Pacific Islander), Hispanic ethnicity (not Hispanic or Latino, Hispanic or Latino), and sex (Vintage 2020), prepared under a collaborative arrangement with the U.S. Census Bureau. Population estimates for states released September 21, 2021, are available at https://www.cdc.gov/nchs/nvss/bridged_race/data_documentation.htm. Population estimates for territories are the 2020 mid-year estimates from the U.S. Census Bureau International Data Base, accessed on March 15, 2022, at https://www.census.gov/data-tools/demo/idb/#/country?YR_ANIM=2022. The choice of population denominators for incidence is based on the availability of population data at the time of publication preparation.
  4. Annual tables for 2016 and later years are available on CDC WONDER.
  5. Annual summary reports from 1993–2015 are available as published in the Morbidity and Mortality Weekly Report.
  6. NNDSS annual tables since 1952 are available at CDC Stacks (once in CDC Stacks, select "Annual Reports" in the "Genre" box to the left).
  7. For most conditions, national incidence rates are calculated as the number of reported cases for each infectious disease or condition divided by the U.S. resident population for the specified demographic population or the total U.S. resident population, multiplied by 100,000. When a national notifiable infectious condition is associated with a specific age restriction, the same restriction was applied to the population in the denominator of the incidence rate calculation. In addition, population data from reporting jurisdictions in which the disease or condition was not reportable or not available were excluded from the denominator of the incidence rate calculations.

    Age restrictions in the numerator and denominator are applied for the following childhood conditions:

    • Zika virus disease, congenital (age restriction in numerator and denominator is <1 year)
    • Zika virus infection, congenital (age restriction in numerator and denominator is <1 year)
    • Haemophilus influenzae, invasive disease <5 years (age restriction in numerator and denominator is <5 years)
    • Invasive pneumococcal disease <5 years (age restriction in numerator and denominator is <5 years)
    • Influenza associated pediatric mortality (age restriction in numerator and denominator is <18 years)
    • Infant botulism (age restriction in numerator and denominator is <1 year)
    • Congenital rubella syndrome (age restriction in numerator and denominator is <1 year)
    • Perinatal hepatitis B infection (age restriction in numerator is ≤24 months, denominator is <24 months)
    • Perinatal hepatitis C infection (age restriction in numerator is ≤36 months, denominator is <36 months).

    Data for congenital syphilis are aggregated by the infant's year of birth. The rate for congenital syphilis is based upon the number of reported cases per 100,000 live births, using natality data for 2020 (National Center for Health Statistics Natality 2020, as compiled from data provided by the Vital Statistics Cooperative Program). Congenital syphilis cases are usually assigned to the mother's state of residence at the time of delivery. The mother's race and ethnicity are used for race- and ethnicity-specific rates of congenital syphilis cases.

  8. Surveillance data reported by other CDC programs might vary from data reported in these tables because of differences in 1) the date used to aggregate the data, 2) the timing of reports, 3) the source of the data, 4) surveillance case definitions, and 5) policies regarding case jurisdiction (i.e., which jurisdiction should submit the case notification to CDC).
  9. The following reporting areas may have incomplete data, due to technical or programmatic challenges while reconciling data during the COVID-19 pandemic: California, Guam, and Minnesota.
  10. The following reporting areas may have incomplete data due to updates made to their data after the 2020 reconciliation period ended and there was not sufficient time before publication of the annual tables to confirm the updated counts: Idaho, Kansas, Maryland, Vermont, and Virgin Islands.
  11. Of the reporting areas that submitted 2020 aggregate COVID-19 data to CDC, three did not submit probable cases. New York (excluding New York City) and Utah did not collect probable cases. U.S. Virgin Islands collected probable cases, but did not report them to CDC.
  12. Disease data presented in the 2020 tables reflect impacts of the COVID-19 pandemic, such as changes in exposure-related behavior, healthcare-seeking behavior, disease reporting, and public health investigations.
Suggested Citation: Acknowledgment:
  • CDC acknowledges the local, state, and territorial health departments that collected the data from a range of case ascertainment sources (e.g., healthcare providers, hospitals, laboratories) and reported these data to CDC's National Notifiable Diseases Surveillance System.