Prevented perinatal HIV infections in the era of antiretroviral prophylaxis and treatment, United States, 1994-2020.

Objective: The primary aim of this serial cross-sectional analysis is to estimate the total number of prevented perinatal HIV transmissions from the time of the initial recommendation for perinatal zidovudine (ZDV) prophylaxis in 1994 through 2020 in the US.

Methods: The estimated number of prevented transmissions was calculated as annual differences between expected and observed numbers of perinatal HIV transmissions. Annual expected number of transmissions was estimated by multiplying the annual number of births to women with HIV by 0.2255 (22.55%), i.e., the transmission rate of the control group in the ACTG Protocol 076 trial. We used published point estimates or, if only ranges were given, the midpoints of those ranges as the best estimates of the annual numbers of births to women with HIV and infants with perinatal HIV. When data were not available, we linearly interpolated or extrapolated the available data to obtain estimated numbers for each year.

Results: Between 1978 and 2020, the approximate number of live births to women with HIV was 191 267 (95% confidence interval [CI] 190 392-192 110) and for infants with diagnosed perinatal HIV, it was 21 379 (95% CI 21 088-21 695). Since 1994, the annual number of infants born with HIV decreased from 1263 (95% CI 1194-1333) to 33 in 2019 (95% CI 22-45) and 36 in 2020 (95% CI 25-48), corresponding to a 97% reduction. Cumulatively, an estimated total of 22 732 (95% CI 21 340-24 462) perinatal HIV infections were prevented from 1994 through to 2020.

Conclusion: The elimination of perinatal HIV transmission-accompanied by the cumulative number of prevented cases exceeding that of perinatal HIV infections-is a major public health achievement in the US.