Acute HIV infection among pregnant women in Malawi

Abstract

There are limited data on acute HIV infection (AHI) prevalence during pregnancy. Malawian pregnant women admitted in the third trimester and meeting eligibility criteria underwent dual HIV rapid antibody testing. AHI prevalence was retrospectively detected through HIV RNA pooling of seronegative plasma. Among 3,825 pregnant women screened, dual HIV rapid testing indicated that 30.2% were HIV positive, 69.7% were HIV negative, and 0.1% were indeterminate. Sensitivity and specificity of dual rapid testing was 99.0% and 98.7%, respectively. Of 2,666 seronegative specimens, 2,327 had samples available for HIV RNA pooling; 5 women (0.21%) (95% confidence interval, 0.03-0.40%) had AHI with a median peripartum viral load of 1,324,766 copies/mL. Pregnant women are at risk for AHI, warranting counseling of all women and their sexual partners about incident HIV during pregnancy. Dual HIV rapid tests have high sensitivity and specificity. HIV testing should be repeated in the third trimester and/or at delivery.

Figure 1

HIV testing results from screening and retrospective detection of acute HIV infection. ^†Only one rapid test performed.

Figure 2

HIV testing results applied to sensitivity and specificity calculations with viral load versus western blot as the gold standard. ^aNot all samples underwent Western blot testing, precluding use of Western blot as the gold standard in sensitivity and specificity calculation.