Socio-economic and environmental protective/risk factors for severe malaria in Thailand

We conducted a cross-sectional study to identify the socio-economic and env ironmental protective/risk factors for severe malaria in Thailand. Forty-si x cases of severe malaria, 72 cases of non-severe malaria with high parasit e biomass and 40 mild malaria cases were included. When comparing severe ma laria and non-severe malaria with high parasite biomass, specific logistic regression models showed a significant protective effect for helminths, adj usted odds ratio 0.24 (0.07-0.78) for low body mass index (BMI), adjusted o dds ratio 0.11 (0.02-0.58). When comparing severe and mild malaria, a longe r residence duration, adjusted odds ratio 0.36 (0.09-0.83) and the use of a ntimalarial self-medication. adjusted odds ratio 0.08 (0.009-0.84) were ass ociated with protection from severe malaria. Using stepwise logistic regres sion with all the variables inserted in the model yielded similar results. These findings suggest specific immunity and self-medication control parasi te multiplication whereas helminths and malnutrition more specifically affe ct the pathogenesis of severe malaria. (C) 2001 Elsevier Science B.V. All r ights reserved.