The most efficient method of tsetse control remains the application of insecticides to that vegetation which provides the flies' resting sites. This paper briefly examines the observed toxic effects of insecticides on non-target organisms, which depends on the compound used, on its formulation and on the application technique. The importance is stressed of initiating research on toxicology and on the population dynamics of a few non-target species affected by insecticide applications. The problems of insecticide applications in game reserves are discussed. Following tsetse elimination, intensified efforts must be made to protect the fauna, within the framework of a general management programme for the whole of the reclaimed territory. The possibility of a rational exploitation of the natural fauna as a source of meat for human consumption is also mentioned.

In south-eastern Uganda the natural hosts of Glossina pallidipes, G. fuscipes fuscipes and G. brevipalpis appear to influence trypanosome infection rates in these vectors. The transmission index of these vectors also differs. Temperature is yet another factor affecting trypanosome infection rates in these tsetses. Other factors probably also form important components in the transmission cycle. In this region of Uganda and its contiguous lake shore area of Kenya there are extant foci of the infections, and man and his symbiotic livestock are exposed to a high challenge of trypanosomiases. Furthermore, in this high endemic/enzootic ecological zone of tropical Africa, the transmission of trypanosome infections to the adventitious hosts, via the tsetse vectors, depends upon a variety of complex interacting factors.