3 Effects of land-use changes on malaria vectors in Kenyan highlands(Ecology of African Malaria,Symposium lecture,Abstract,The 58th Annual Meeting of the Japan Society of Medical Entomology and Zoology)

Siiice the mid 80's, malaria ourbreaks have frequently occurred in the east African highlands where malaria was proviously rare.We hypothesized that land-use changes have becn panially attributed to the highland malaria.Ib test this hypothesis, we detemined whether the distribution of a malaria vector species C4n(zpheles gambiae) was associated with the current land cover types in Kenyan highlands.We also examined the effects of diiferent land cover types on production of the malaria vectot The distribution of A. gambiae larvae was negatively associated wirh forests, and most breeding sites were found in cultivated areas in yalley bottoms.The land cover types also affected oviposhion site preference and egg hatehal)ility ofA, gambiae.Anopheles gambiae preferred water from farmland for oviposition and mortality of eggs were lower in the fatmland water Under natural conditions, emergence traps collected A. gambiae adults only ffom habitats in fatmlands.Larval mortality was lower in the hal)hats of farmlands than in those of forests and permanent wetlands, and the larval to pupal development time was significaritly sborter in fattnlands.These results suggest that land-use changes, such as deforestatioq have afliected the distribution and production of malaria vectors in Kenyan highlands.