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

TABLE 2j. Annual reported cases* of notifiable diseases, by region and reporting area, United States, U.S. Territories, and Non-U.S. Residents, 2021†
Reporting Area Listeriosis § Lyme disease
Total Confirmed Probable Total Confirmed Probable
U.S. Residents, excluding U.S. Territories 977 941 36 24,610 16,211 8,399
New England 70 68 2 3,570 2,446 1,124
Connecticut 19 19 — 541 392 149
Maine 6 6 — 1,510 1,144 366
Massachusetts 30 28 2 27 4 23
New Hampshire 5 5 — 397 226 171
Rhode Island 6 6 — 980 572 408
Vermont 4 4 — 115 108 7
Middle Atlantic 213 210 3 9,424 6,734 2,690
New Jersey 42 42 — 3,518 2,469 1,049
New York (excluding New York City) 44 44 — 2,187 1,504 683
New York City 66 63 3 819 428 391
Pennsylvania 61 61 — 2,900 2,333 567
East North Central 146 141 5 4,499 2,746 1,753
Illinois 33 33 — 540 324 216
Indiana 18 16 2 314 164 150
Michigan 36 33 3 862 460 402
Ohio 42 42 — 590 561 29
Wisconsin 17 17 — 2,193 1,237 956
West North Central 36 33 3 2,350 1,152 1,198
Iowa 3 3 — 359 87 272
Kansas 1 1 — 22 6 16
Minnesota 14 12 2 1,902 1,033 869
Missouri 14 13 1 7 1 6
Nebraska 3 3 — 10 6 4
North Dakota — — — 34 13 21
South Dakota 1 1 — 16 6 10
South Atlantic 208 200 8 4,286 2,887 1,399
Delaware 8 8 — 140 59 81
District of Columbia 4 4 — 91 53 38
Florida 57 54 3 193 109 84
Georgia 37 37 — 35 9 26
Maryland 28 28 — 916 560 356
North Carolina 26 25 1 338 149 189
South Carolina 14 11 3 76 46 30
Virginia 29 28 1 705 468 237
West Virginia 5 5 — 1,792 1,434 358
East South Central 38 37 1 150 68 82
Alabama 12 12 — 51 24 27
Kentucky 6 5 1 41 7 34
Mississippi 1 1 — 1 1 —
Tennessee 19 19 — 57 36 21
West South Central 78 76 2 47 20 27
Arkansas 4 4 — 11 — 11
Louisiana 9 8 1 4 — 4
Oklahoma 9 9 — — — —
Texas 56 55 1 32 20 12
Mountain 36 32 4 61 39 22
Arizona 9 8 1 3 3 —
Colorado 12 12 — — — —
Idaho 5 4 1 6 5 1
Montana 2 2 — 13 8 5
Nevada 3 3 — 17 8 9
New Mexico 3 1 2 2 2 —
Utah 2 2 — 18 13 5
Wyoming — — — 2 — 2
Pacific 152 144 8 223 119 104
Alaska 1 1 — — — —
California 106 101 5 106 78 28
Hawaii 8 8 — N N N
Oregon 18 17 1 74 15 59
Washington 19 17 2 43 26 17
U.S. Territories 3 3 — 1 1 —
American Samoa N N N N N N
Commonwealth of Northern Mariana Islands — — — — — —
Guam — — — — — —
Puerto Rico 3 3 — N N N
U.S. Virgin Islands — — — 1 1 —
Non-U.S. Residents — — — — — —
Total 980 944 36 24,611 16,212 8,399
  • —: No reported cases — The reporting jurisdiction did not submit any cases to CDC.
  • N: Not reportable — The disease or condition was not reportable by law, statute, or regulation in the reporting jurisdiction.
  • U: Unavailable — The data are unavailable.
  • * Cases are assigned to the reporting jurisdiction submitting the case to NNDSS if the case's country of usual residence is the United States, a U.S. territory, unknown, or country is not reported; otherwise, the case is assigned to the Non-U.S. Residents' category. Country of usual residence is currently not reported by all jurisdictions or for all conditions because this data element is only available in the HL7 generic version 2 and disease-specific message mapping guides. If a jurisdiction sends data in legacy formats, they are not able to send this information. For further information on interpretation of these data, see https://www.cdc.gov/nndss/data-statistics/readers-guides/.
  • † To calculate rates, use the populations provided in Table 8. Note that calculation of rates for the following conditions uses population subgroups as described in note #7 and population counts presented in Table 8: Zika virus infection, congenital; Zika virus disease, congenital; Infant botulism; Congenital rubella syndrome; Perinatal Hepatitis B infection; Perinatal Hepatitis C infection; Haemophilus influenzae, invasive disease; Invasive pneumococcal disease; and Influenza-associated pediatric mortality. Also see Notes #3 and #7.
  • § 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.
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 2021 annual tables were officially closed on March 29, 2023.
  2. The list of national notifiable Infectious diseases and conditions for 2021 and their national surveillance case definitions are available by navigating to the Surveillance Case Definitions | CDC web page, selecting "2021" for the notifiable condition list year, checking "Infectious" conditions, and clicking "Get Notifiable List by Year". 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. On June 17, 2021, a revision to the COVID-19 national surveillance case definition was approved, effective September 1, 2021. Publication criteria for the finalized 2021 data are available at https://wonder.cdc.gov/nndss/documents/2021_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 22, 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 and denominator is ≤24 months)
    • Perinatal hepatitis C infection (age restriction in numerator and 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 2021 (National Center for Health Statistics Natality 2021, 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. Disease data presented in the 2021 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.