A tsetse fly capture net. Flies, attracted by the colour, enter through openings in the base and are thus trapped. - - Trypanosomiasis Control. Trypanosomiasis ("sleeping sickness") is a wasting human disease which also attacks domestic animals and herds and is endemic in certain parts of Africa. The tsetse fly assumes the microscopic parasites while feeding on blood, and they may then be transferred from one host to another within a short space of time. Studies are being conducted at the "Centre de recherches sur la trypanosomiase animale" (CRTA, near Bobo-Dioulasso, to understand the vectors and find effective controls against the disease.