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

TABLE 2e. Annual reported cases* of notifiable diseases, by region and reporting area, United States, 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.
Reporting Area Cholera Coccidioidomycosis Coronavirus Disease 2019 (COVID-19) Cryptosporidiosis Cyclosporiasis
Total Confirmed Probable § Total Confirmed Probable
U.S. Residents, excluding U.S. Territories 1 19,220 21,149,731 19,179,356 1,970,375 7,648 5,861 1,787 2,689
New England — 2 769,174 714,300 54,874 344 212 132 38
Connecticut — N 200,387 188,284 12,103 33 16 17 7
Maine — N 27,223 23,066 4,157 72 48 24 —
Massachusetts — N 396,415 379,712 16,703 120 116 4 24
New Hampshire — 2 47,373 34,558 12,815 40 4 36 3
Rhode Island — — 90,476 81,570 8,906 23 23 — 4
Vermont — N 7,300 7,110 190 56 5 51 —
Middle Atlantic — — 2,277,354 2,101,519 175,835 945 757 188 271
New Jersey — N 587,202 533,785 53,417 118 117 1 104
New York (excluding New York City) — N 559,358 559,358 — 390 320 70 48
New York City — N 460,881 406,349 54,532 138 138 — 119
Pennsylvania — N 669,913 602,027 67,886 299 182 117 N
East North Central — 89 3,378,700 3,080,930 297,770 1,457 1,123 334 477
Illinois — N 1,036,452 964,851 71,601 242 180 62 320
Indiana — 14 527,039 466,598 60,441 156 138 18 7
Michigan — 38 547,421 504,839 42,582 246 201 45 21
Ohio — 11 740,300 657,960 82,340 326 247 79 56
Wisconsin — 26 527,488 486,682 40,806 487 357 130 73
West North Central — 160 1,758,317 1,585,391 172,926 1,251 963 288 789
Iowa — N 287,449 246,587 40,862 368 258 110 269
Kansas — 6 258,115 210,587 47,528 79 58 21 59
Minnesota — 99 430,362 413,995 16,367 369 319 50 143
Missouri — 22 435,991 397,407 38,584 228 200 28 186
Nebraska — 16 153,404 136,122 17,282 107 94 13 88
North Dakota — 10 92,526 89,468 3,058 24 7 17 22
South Dakota — 7 100,470 91,225 9,245 76 27 49 22
South Atlantic — 3 3,777,022 3,304,525 472,497 1,200 873 327 310
Delaware — — 59,892 57,512 2,380 25 20 5 1
District of Columbia — N 30,915 30,190 725 12 12 — —
Florida — N 1,338,409 1,154,911 183,498 291 137 154 153
Georgia — N 669,200 567,046 102,154 250 225 25 57
Maryland — 3 316,410 291,070 25,340 72 72 — 18
North Carolina — N 574,440 520,522 53,918 205 179 26 35
South Carolina — N 338,459 303,661 34,798 85 85 — 13
Virginia — N 363,731 308,532 55,199 198 86 112 28
West Virginia — N 85,566 71,081 14,485 62 57 5 5
East South Central — 13 1,457,516 1,191,231 266,285 606 480 126 66
Alabama — 5 368,668 300,452 68,216 137 85 52 9
Kentucky — 8 277,976 223,856 54,120 222 157 65 N
Mississippi — N 225,195 151,998 73,197 64 63 1 N
Tennessee — N 585,677 514,925 70,752 183 175 8 57
West South Central 1 16 2,727,870 2,401,707 326,163 639 556 83 654
Arkansas — 8 244,061 200,514 43,547 66 48 18 19
Louisiana 1 8 345,176 308,146 37,030 106 79 27 54
Oklahoma — N 335,151 272,548 62,603 102 93 9 N
Texas — N 1,803,482 1,620,499 182,983 365 336 29 581
Mountain — 11,837 1,877,431 1,789,070 88,361 562 380 182 59
Arizona — 11,527 590,745 557,539 33,206 80 60 20 2
Colorado — N 353,958 335,437 18,521 149 101 48 37
Idaho — N 142,286 117,664 24,622 88 76 12 N
Montana — 15 81,460 76,194 5,266 48 48 — 1
Nevada — 189 228,137 228,093 44 21 17 4 N
New Mexico — 50 149,528 149,455 73 36 18 18 4
Utah — 55 285,533 285,533 — 128 52 76 12
Wyoming — 1 45,784 39,155 6,629 12 8 4 3
Pacific — 7,100 3,126,347 3,010,683 115,664 644 517 127 25
Alaska — N 47,144 44,390 2,754 6 2 4 2
California — 7,090 2,669,999 2,574,414 95,585 367 318 49 12
Hawaii — N 21,956 21,419 537 4 3 1 —
Oregon — 10 117,348 112,860 4,488 95 37 58 —
Washington — N 269,900 257,600 12,300 172 157 15 11
U.S. Territories — — 92,248 86,889 5,359 3 3 — —
American Samoa — N — — — N N N N
Commonwealth of Northern Mariana Islands — — 184 122 62 — — — —
Guam — — 7,336 7,154 182 — — — —
Puerto Rico — N 82,692 77,577 5,115 3 3 — —
U.S. Virgin Islands — — 2,036 2,036 — — — — —
Non-U.S. Residents — 4 — — — 4 3 1 —
Total 1 19,224 21,241,979 19,266,245 1,975,734 7,655 5,867 1,788 2,689
  • —: 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 use population subsets 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.
  • § Please see Note #11.
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.