Helminth infection and eosinophilia and the risk of Plasmodium falciparum malaria in 1- to 6-year-old children in a malaria endemic area.
BACKGROUND
Helminth infection is common in malaria endemic areas, and an interaction between the two would be of considerable public health importance. Animal models suggest that helminth infections may increase susceptibility to malaria, but epidemiological data has been limited and contradictory.


RESULTS
In a vaccine trial, we studied 387 one- to six-year-old children for the effect of helminth infections on febrile Plasmodium falciparum malaria episodes. Gastrointestinal helminth infection and eosinophilia were prevalent (25% and 50% respectively), but did not influence susceptibility to malaria. Hazard ratios were 1 for gastrointestinal helminth infection (95% CI 0.6-1.6) and 0.85 and 0.85 for mild and marked eosinophilia, respectively (95% CI 0.56-1.76 and 0.69-1.96). Incident rate ratios for multiple episodes were 0.83 for gastro-intestinal helminth infection (95% CI 0.5-1.33) and 0.86 and 0.98 for mild and marked eosinophilia (95% CI 0.5-1.4 and 0.6-1.5).


CONCLUSIONS
There was no evidence that infection with gastrointestinal helminths or urinary schistosomiasis increased susceptibility to Plasmodium falciparum malaria in this study. Larger studies including populations with a greater prevalence of helminth infection should be undertaken.
Bejon
Philip
P
Kenya Medical Research Institute, Centre for Geographical Medicine Research (Coast), Kilifi, Kenya. pbejon@kemri-wellcome.org
Mwangi
Tabitha W
TW
Lowe
Brett
B
Peshu
Norbert
N
Hill
Adrian V S
AV
Marsh
Kevin
K
D000367:Age Factors; D000818:Animals; D002648:Child; D002675:Child, Preschool; D004802:Eosinophilia / Q000150:complications* / Q000469:parasitology; D005260:Female; D005767:Gastrointestinal Diseases / Q000150:complications / Q000469:parasitology; D006373:Helminthiasis / Q000150:complications* / Q000469:parasitology; D006801:Humans; D007223:Infant; D053208:Kaplan-Meier Estimate; D007630:Kenya; D017780:Malaria Vaccines / Q000008:administration & dosage*; D016778:Malaria, Falciparum / Q000150:complications* / Q000469:parasitology / Q000517:prevention & control*; D008297:Male; D015995:Prevalence; D012307:Risk Factors; D012553:Schistosomiasis haematobia / Q000150:complications / Q000469:parasitology
D017780:Malaria Vaccines