Trends in perinatal transmission of HIV/AIDS in the United States

Context Since 1994, the US Public Health Service (PHS) has recommended rout ine, voluntary prenatal human immunodeficiency virus (HIV)testing and zidov udine therapy to reduce perinatal HIV transmission. Objective To describe trends in incidence of perinatal AIDS and factors con tributing to these trends, particularly the effect of PHS perinatal HIV rec ommendations. Design, Setting, and Participants Analysis of nationwide AIDS surveillance data and data from HIV-reporting states through June 1998. Main Outcome Measures Trends in AIDS by year of diagnosis, incidence rates of AIDS and Pneumocystis carinii pneumonia (PCP) among infants younger than 1 year from US natality data for birth cohorts 1988 to 1996; expected numb er of infants with AIDS from national serosurvey data; and zidovudine use d ata from selected HIV-reporting states. Results Perinatal AIDS cases peaked in 1992 and then declined 67% from 1992 through 1997, including an 80% decline in infants and a 66% decline in chi ldren aged 1 to 5 years. Rates of AIDS among infants (per 100 000 births) d eclined 69%, from 8.9 in 1992 to 2.8 in 1996 compared with a 17% decline in births to HIV-infected women from 1992 (n = 6990) to 1995 (n = 5797). Amon g infants, PCP rates per 100 000 declined 67% (from 4.5 in 1992 to 1,5 in 1 996), similar to the decline in other AIDS conditions. The percentage of pe rinatally exposed children born from 1993 through 1997 whose mothers were t ested for HIV before giving birth increased from 70% to 94%; the percentage who received zidovudine increased from 7% to 91%. Conclusions According to these data, substantial declines in AIDS incidence were temporally associated with an increase in zidovudine use to reduce pe rinatal HIV transmission, demonstrating substantial success in implementing PHS guidelines. Reductions in the numbers of births and effects of therapy in delaying AIDS do not explain the decline.