The effects of maternal helminth and malaria infections on mother-to-child HIV transmission.
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.


METHODS
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 helminthes 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 helminthes (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).


CONCLUSIONS
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.
Gallagher
Maureen
M
Center for Global Health and Diseases and Center for AIDS Research, Case Western Reserve University, Cleveland, OH 44106-7286, USA.
Malhotra
Indu
I
Mungai
Peter L
PL
Wamachi
Alex N
AN
Kioko
John M
JM
Ouma
John H
JH
Muchiri
Eric
E
King
Christopher L
CL
D000328:Adult; D002675:Child, Preschool; D015331:Cohort Studies; D016207:Cytokines / Q000378:metabolism; D004605:Elephantiasis, Filarial; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005312:Fetal Blood / Q000378:metabolism; D015658:HIV Infections / Q000150:complications*; D006373:Helminthiasis / Q000150:complications*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D018445:Infectious Disease Transmission, Vertical; D007630:Kenya; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000469:parasitology / Q000821:virology; D015597:Pregnancy Complications, Parasitic / Q000469:parasitology / Q000821:virology; D012189:Retrospective Studies; D012307:Risk Factors; D012552:Schistosomiasis
D016207:Cytokines