The effect of anthelmintic treatment during pregnancy on HIV plasma viral load: results from a randomized, double-blind, placebo-controlled trial in Uganda.

BACKGROUND To investigate the effect of helminth infections and their treatment during pregnancy on HIV load, we conducted a 2 × 2 factorial randomized controlled trial of albendazole versus placebo and praziquantel versus placebo in pregnant women in Entebbe, Uganda. METHODS Two hundred sixty-four HIV-infected pregnant women from the Entebbe Mother and Baby Study (ISRCTN 32849447) were included in this analysis. Women were tested for helminth infections at enrollment, and mean HIV load was compared between infected and uninfected groups. The effect of anthelmintic treatment on HIV load was evaluated at 6 weeks after treatment and at delivery using linear regression and adjusting for enrollment viral load. RESULTS Hookworm and Trichuris infections were associated with higher mean viral load at enrollment [adjusted mean difference 0.24 log10 copies/mL, 95% confidence interval (CI): 0.01 to 0.47, P = 0.03, and 0.37 log(10) copies/mL, 95% CI: 0.00 to 0.74, P = 0.05, respectively]. There were no associations between viral load and other helminth species. There was some evidence that albendazole reduced viral load at 6 weeks after treatment (adjusted mean difference -0.17, 95% CI: -0.36 to 0.01, P = 0.07); however, this effect did not differ according to mother's hookworm infection status and had diminished at delivery (adjusted mean difference -0.11, 95% CI: -0.28 to 0.07, P = 0.23). There was no effect of praziquantel treatment on HIV load at any time point. CONCLUSIONS Infection with some soil-transmitted helminth species is associated with increased HIV load in pregnancy. Treatment with albendazole causes a small decrease in HIV load; however, this may not represent a direct effect of worm removal.