Frequent detection of acute HIV infection in pregnant women.

BACKGROUND: Universal prenatal HIV antibody testing, which does not detect acute HIV, is standard for pregnant women in the United States. Unrecognized HIV acquisition during pregnancy may result in higher rates of perinatal transmission.
OBJECTIVE: To determine the prevalence of acute (antibody-negative) HIV infection in pregnant women and to assess the potential for prompt initiation of antiretroviral therapy to prevent perinatal transmission.
METHODS: From 1 November 2002 to 30 April 2005, all publicly funded HIV testing sites participated in North Carolina's Screening and Tracing Active Transmission (STAT) Program, which retested all specimens that were HIV antibody negative for HIV RNA using specimen pooling. All patients with acute HIV infection were immediately traced for evaluation, confirmatory testing, counseling, and referral services. For this study, all pregnant women with acute HIV were immediately initiated onto antiretroviral therapy and followed prospectively for pregnancy outcomes.
RESULTS: During the study period, 443 women were HIV positive by antibody testing; 15 were HIV antibody negative but positive by RNA assay and of these five were pregnant at the time of testing. The pregnant women received antiretroviral drugs and delivered HIV-uninfected infants. Maternal testing records of all six HIV-infected infants born in North Carolina showed three mothers with chronic HIV infection and three HIV antibody negative at private prenatal testing facilities.
CONCLUSIONS: In resource-rich settings, a substantial proportion of residual perinatal transmission may be from HIV acquisition during pregnancy. Standard antibody tests miss acute HIV infection and so algorithms that include pooled HIV RNA testing may improve its detection and represent a further opportunity to prevent perinatal transmission.