The effects of maternal helminth and malaria infections on mother-to-child HIV transmission
Gallagher, M.; Malhotra, I.; Mungai, P.L.; Wamachi, A.N.; Kioko, J.M.; Ouma, J.H.; Muchiri, E.; King, C.L.
Aids 19(16): 1849-1855
2005
ISSN/ISBN: 0269-9370 PMID: 16227793 DOI: 10.1097/01.aids.0000189846.90946.5dDocument Number: 257540
Objective: To investigate the effect of helminth and/or malaria infection on the risk of HIV infection in pregnant women and its transmission to their offspring. Design: A retrospective cohort study of pregnant Kenyan women and their offspring from term, uncomplicated vaginal deliveries (n=936) with a nested case-control study. Methods: We determined the presence of HIV, malaria, schistosomiasis, lymphatic filariasis, and intestinal helminths in mothers and tested for HIV antibodies in 12-24 month-old offspring of HIV-positive women. We related these findings to the presence of cord blood lymphocyte activation and cytokine production in response to helminth antigens. Results: HIV-positive women (n=83, 8.9% of all women tested) were 2-fold more likely to have peripheral blood and/or placental malaria (P<0.025) and a 2.1-fold greater likelihood of lymphatic filariasis infection (P<0.001) compared to location-and-parity matched HIV-negative women. Women with HIV and malaria tended to show an increased risk for mother-to-child-transmission (MTCT) of HIV, although this difference was not significant. MTCT of HIV, however, was significantly higher in women co-infected with one or more helminths (48%) verses women without helminth infections (10%, P<0.01; adjusted odds ratio, 7.3; 95% confidence interval, 2.4-33.7). This increased risk for MTCT of HIV correlated with cord blood lymphocytes production of interleukin-5/interleukin-13 in response to helminth antigens (P<0.001). Conclusion: Helminth co-infection is associated with increased risk for MTCT of HIV, possibly by a mechanism in which parasite antigens activates lymphocytes in utero. Treatment of helminthic infections during pregnancy may reduce the risk of MTCT of HIV.