Distribution Of Tsetse Flies And Significance To The Control Of African Trypanosomiasis In Busia County, Kenya

Abstract

Background: Tsetse flies are the cyclical vectors of both human and animal diseases in Sub-Saharan Africa. Since 2012, Kenya has not recorded a case of human trypanosomiasis. However, African animal trypanosomiasis continues to be a major challenge to livestock production despite decades of control efforts. This study aimed to determine the prevalence of tsetse flies in Busia County post intervention and to build the capacity of local inhabitants in vector control activities. Methods: This cross-sectional study was conducted between May 2018 and December 2018 in Teso South and Teso North sub-counties. Odour-baited biconical traps were deployed for 48 hours in each sampling area and captured tsetse flies were analysed for trypanosome infections. Additionally, training and field demonstrations were conducted as part of capacity building to enhance participation of local inhabitants in tsetse control activities. Results: In Teso South sub-county, 62 tsetse flies were captured in Kwangamor, six in Obekai and 14 in Ngelechom sites. All the captured tsetse flies were classified as G. fuscipes fuscipes. In Teso North sub-county sites of Kapesur, three G. pallidipes were captured, while the Ikapolok sites yielded 12 tsetse flies all G. fuscipes fuscipes. The apparent density of tsetse flies was between 0.08 and 1.55 flies-per trap-per-day across the five study areas with G. fuscipes fuscipes being the dominant species. Microscopic examination of 72 G. fuscipes fuscipes identified three T vivax and one T. congolense positive tsetse flies. No trypanosomes were observed in all the G. pallidipes. Overall infection rate of 1.39% and 4.17% was observed for T. congolense and T. vivax respectively. With regards to capacity building, a total of 26 community members were trained on tsetse fly control activities. Out of which five were selected as focal persons and were further trained on integrated vector management techniques and tsetse survey methods. Conclusions: Tsetse flies in Teso South sub-county, albeit low density, harbour trypanosomes. This calls for an urgent attention to stop potential spread and transmission. Moreover, training of local inhabitants in tsetse control activities will help to strengthen and sustain efforts towards elimination of African trypanosomiasis in Busia County.