SEVERE CHILDHOOD MALARIA IN 2 AREAS OF MARKEDLY DIFFERENT FALCIPARUM TRANSMISSION IN EAST-AFRICA

Malaria remains a major public health challenge in sub-Saharan Africa, yet our knowledge of the epidemiology of malaria in terms of patterns of mortality and morbidity is limited. We have examined the presentat ion of severe, potentially life-threatening malaria to district hospit als in two very different transmission settings: Kilifi, Kenya with lo w seasonal transmission and Ifakara, Tanzania with high seasonal trans mission. The minimum annual rates of severe disease in children below five years in both populations were similar (46 per 1000 children in K ilifi and 51 per 1000 children in Ifakara). However, there were import ant differences in the age and clinical patterns of severe disease; tw ice as many patients were under one year of age in Ifakara compared wi th Kilifi and there was a four fold higher rate of cerebral malaria an d three fold lower rate of malaria anaemia among malaria patients at K ilifi compared with Ifakara. Reducing malaria transmission in Ifakara by 95%, for example with insecticide-treated bed nets, would result in a transmission setting comparable to that of Kilifi and although this reduction may yield early successes in reducing severe malaria morbid ity and mortality in young, immunologically naive children, place thes e same children at increased risk at older ages of developing severe a nd potentially different manifestations of malaria infection hence pro ducing no net cohort gain in survivorship from potentially fatal malar ia.