Distribution of AIDS diagnoses in the U.S. in 2021, by transmission category

Transmission category is the term for the classification of cases that summarizes a person’s possible HIV risk factors; the summary classification results from selecting, from the presumed hierarchical order of probability, the one risk factor most likely to have resulted in HIV transmission. The exception is men who had sexual contact with other men and injected drugs; this group makes up a separate transmission category. Data have been statistically adjusted to account for missing transmission category. 

AIDS diagnoses refer to the number of cases confirmed by laboratory or clinical evidence in 2021. Data are presented based on a person’s most recent known address as of December 31 of the queried year. Because of delays in the reporting of deaths, prevalence data are based on a 12-month reporting delay to allow data to be reported to CDC (prevalence data are considered preliminary until 12-months after the specified year to account for delays in reporting). 

Cases with unknown transmission are not displayed; therefore, the sum of the state totals will not match the national total, which includes cases with unknown transmission.

* Includes hemophilia, blood transfusion, perinatal exposure, and risk factor not reported or not identified. 

Release date represents the date figures were accessed.