ABSTRACT
L`Afrique centrale est une region historique de la trypanosomiase humaine africaine. A l`aube du vingt et unieme siecle; la maladie reste epidemique en Angola et en Republique Democratique du Congo et preoccupante dans les autres pays de la region. Malgre la mise en ouvre de nombreux efforts de lutte; le seuil de l`elimination fixe a 1 cas par an pour 10.000 habitants exposes est encore loin d`etre atteint. La transmission se poursuit dans les foyers a faible niveau d`endemicite du fait de l`absence de lutte antivectorielle ciblee au point de contact homme-glossines. Des cas d`echecs therapeutiques sont observes dans certains foyers. De plus en plus; des foyers quiescents se remettent en activite. Une strategie de lutte associant le depistage-traitement des malades et la lutte antivectorielle permettrait d`atteindre plus rapidement l`objectif de l`elimination de la maladie dans les foyers. La presence d`un personnel qualifie et equipe permettrait d`assurer une surveillance sentinelle dans les foyers
Subject(s)
Drug Resistance , Prevalence , Trypanosoma , Trypanosomiasis, African , Tsetse FliesABSTRACT
The pyrethroid insecticide lambda-cyhalothrin was evaluated in field trials against Glossina f.fuscipes and sleeping sickness transmission in Iyolwa sub-county; Tororo District; Uganda. The insecticide was applied selectively to the resting-sites of tsetse; by bush-spraying; using 10pc wettable powder (10WP) formulation at an application rate of 11.6 g a.i./ha over an area of 28 km2; or by a 2pc Electrodyn formulation (2ED) applied at 0.9 g a.i./ha over 30 km2. In a third trial area of 32 km2; 215 pyramidal traps treated with lambda-cyhalothrin 100 mg/m2 were set. The best impact was obtained with 10WP 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-treated traps 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