Interactions between vector and trypanosome in determining the vectorial competence of tsetse flies

Abstract

In order to study the interactions between tsetse flies and trypanosomes and their impact on metacyclogenesis, 5257 teneral flies of both sexes originating from three laboratory strains, Glossina palpalis gambiensis (Maisons-Alfort), G. p. palpalis (Mongo-Bemba) and G. morsitans morsitans (Mall) were used. They were fed once on rats infected with Trypanosoma brucei gambiense (Mba and Phanzu strains), T. b. brucei (EATRO 1125 strain) or T. congolense (IL 1180 clone and Agriumbe stock). Both palpalis strains had no or very low vectorial competence (VC) for all trypanosomes tested, except for T. congolense clone and stock. G. m. morsitans had no VC for both gambiense strains, but had a relatively high VC (32%) for T. b. brucei EATRO 1125. G. m. morsitans had a higher VC for the IL 1180 clone (95.45%) than the Agriumbe stock (48.40%) of T. congolense. These results show the excellent interaction between G. m. morsitans (Mall) and T. congolense IL 1180.