[Seasonal variability in the insecticide resistance and irritability of Anopheles superpictus].

The resistance and irritability to malathion, fenitrothion, propoxur and DDT (WHO insecticide impregnated papers) in Anopheles superpictus from Dangara District were determined three times in season. Complete susceptibility to malathion, fenitrothion and DDT and low resistance to propoxur probably based on knockdown mechanism were noticed. DDT and malathion irritability levels were high, and those for fenitrothion and propoxur were lower. During the season irritability to malathion and fenitrothion (organophosphorous compounds) was slightly decreasing, and in contrast was increasing to propoxur (carbamate). Irritability to DDT (organochloride) considerably fell down in August and achieved the initial level in September again. None of the tested insecticides can be recommended for residual spraying in Dangara District because of high irritability levels in mosquitos or danger of its rapid increase after onset of spraying.