Decline in perinatal HIV transmission in New York State (1997-2000).

BACKGROUND: Perinatal HIV transmission has declined significantly in New York State (NYS) since implementation of a 3-part regimen of zidovudine prophylaxis in the antenatal, intrapartum, and newborn periods. This study describes the factors associated with perinatal transmission in NYS from 1997 to 2000, the first 4 years of NYS's comprehensive program in which all HIV-exposed newborns were identified through universal HIV testing of newborns. METHODS: This population-based observational study included all HIV-exposed newborns whose infection status was known and their mothers identified in NYS through the universal Newborn HIV Screening Program (NSP) from February 1997 to December 2000. Antepartum, intrapartum, newborn, and pediatric medical records of HIV-positive mothers/infants were reviewed for history of prenatal care, antiretroviral therapy (ART), and infant infection status. Risks associated with perinatal HIV transmission were examined. RESULTS: Perinatal HIV transmission declined significantly from 11.0% in 1997 to 3.7% in 2000 (P < 0.05). Prenatal ART was associated with a decline in perinatal HIV transmission both for monotherapy (5.8%, relative risk [RR] = 0.3, 95% confidence interval: 0.2%-0.5%) and combination therapy [2.4%, RR = 0.1, 95% confidence interval: 0.1%-0.2%) compared with no prenatal antiretroviral prophylaxis (P < 0.05). CONCLUSIONS: Public health policies to improve access to care for pregnant women and advances in clinical care, including receipt of appropriate preventive therapies, have contributed to declines in perinatal HIV transmission in NYS.

Prevalence of genotypic drug resistance among a cohort of HIV-infected newborns.

A retrospective, blinded study was conducted to examine the prevalence of antiretroviral drug resistance among a cohort of HIV-infected infants born in 1998 and 1999 in New York State. The earliest available HIV-positive specimen was tested. Most samples were from infants younger than 60 days of age. Genotype data were generated for the protease and reverse transcriptase genes of HIV-1 proviral DNA from 91 infected infants. Eleven infants (12.1%) had provirus with mutations associated with drug resistance, with all three classes of antiretroviral drugs represented. Two infants (2.2%) had mutations associated with resistance to two classes of antiretrovirals. Perinatal antiretroviral drug exposure was examined; it was not found to be significantly associated with the presence of resistance mutations. However, for those infants who had perinatal antiretroviral exposure and genotypic evidence of drug resistance to HIV, the mutations that were detected correlated with at least one antiretroviral from the perinatal period. The prevalence of genotypic drug resistance among this infant cohort is comparable with that found among recently infected adults. These results suggest that resistance testing should be strongly considered for perinatally infected infants, at the earliest possible time point, to avoid use of antiretroviral drugs to which the infant has preexisting resistance.