SEASONAL-VARIATION IN THE PERCEIVED RISK OF MALARIA - IMPLICATIONS FOR THE PROMOTION OF INSECTICIDE-IMPREGNATED BED NETS

Bed nets (mosquito nets), impregnated every 6 months with pyrethroid i nsecticides, are a simple, low-cost malaria control method well suited to conditions in sub-Saharan Africa. As large seasonal variations in levels of net usage may seriously limit the potential impact of the ne ts on malaria transmission, a study was conducted on local definitions of seasons, perceptions of seasonal variation in mosquito populations and incidence of febrile illnesses in Bagamoyo District, Tanzania, to aid in the design of a communication strategy for promoting sustained use of the nets. Both the diagnosis and treatment of febrile illnesse s are affected by what season people think it is, by what illnesses th ey think are common in each season, and also by their perceptions of h ow abundant mosquitoes are. During dry seasons when mosquitoes are sca rce and malaria is thought to be unlikely, it will be difficult to att ain high rates of net usage. It will be necessary to develop locally-a ppropriate messages and communication materials that explain how it is possible that malaria can be a threat even when mosquitoes are few. C ultural consensus analysis was found to be a particularly valuable too l for understanding the reasons behind large variations in local perce ptions of seasonality.