Control of tsetse and trypanosomiasis transmission in Uganda by a application of lambdacyhalothrin

ABSTRACT

The pyrethroid insecticide lambda-cyhalothrin was evaluated in field trials against Glossina f. fuscipes and sleeping sickness transmission in lyolwa sub-county; Tororo District; Eastern Uganda. The isnecticide was applied selectively to the resting-sites of tsetse; by bush-spraying; using 10vettable powder (10WP) formulation at an application rate of 11.6 g.a.i/ha over an area of 32km 2;215 pyramidal traps treated with lambda-cyhalothrin which eliminated tsetse within 1-2 months; whereas G.f.fuscipes persisted at very low density in part of the area treated with 2ED lambda-cyhalothrin. In both treated areas; the numbers of human sleeping sickness cases fell to no more than one per month; compared with four to twelve per month previously. The overall rate of cattle trypanosomiasis (T.brucei and T.vivax) was also reduced slightly. Insecticide-treatedtraps remained fully effective for at least 6 months under field conditions; and catches were reduced 20-90-fold. These results in the control of tsetse and trypanosomiasis transmission lead us to recommend lambda-cyhalothrin for tsetse control operations