[Effects of sublethal doses of deltamethrin on the pair Glossina morsitans morsitans-Trypanosoma (Nannomonas) congolense].

The presence of Trypanosoma in Glossina morsitans morsitans induced a decrease in the physiological activity which is expressed in particular by a statistically higher mortality rate of infected flies. A similar effect appears with sublethal doses of deltamethrin either in infected or non infected insects. A cumulative activity of both effects was also observed in infected and treated flies. Sublethal doses of the pyrethroid compound showed a delay in feeding, abortions and larval clampings. Moreover, deltamethrin demonstrated an intravectorial effect against Trypanosoma which can reduce the transmission ability of flies.