However, they tend to make many short flights every day and these are not all in the same direction. Tsetse flies feed on the blood of a wide range of domestic and wild animals as well as humans and it is whilst feeding that an infected fly transfers the trypanosomes to its host. From the bite, parasites first enter the lymphatic system and then pass into the bloodstream. While taking blood from a mammalian host, an infected tsetse fly injects metacyclic trypomastigotes into skin tissue. Regular screening of communities in areas where tsetse flies are endemic and the culling of wild animal reservoirs, as well as personal approaches such as the use of insect repellent and the wearing of long-sleeved shirts and pants, have also helped reduce the number of cases of sleeping sickness. LIFE CYCLE . their range of vision. Tsetse can fly at about 20 km/h (Gibson et al., 1991) and they are active for something like 30 minutes each day (Bursell & Taylor, 1980). Flies that enter the trap may die because of exposure to an insecticide impregnated in the trap material or because they are exposed to the sun. Thus a trap PUBLIC HEALTH IMPORTANCE. So they could travel up to 10 km every day! Tsetse flies are found in a number of habitats in sub-Saharan Africa, ranging from the rain forest to savannahs. (See footnote) What effect does trypanosomosis have on domestic animals? - the species of tsetse fly - the vegetation - the resting places of host animals (e.g. Migrating flies that pass nearby are also attracted. Tsetse flies, with one exception, are all found in Africa. The tsetse fly (genus Glossina) is a large, brown, biting fly that serves as both a host and vector for the trypanosome parasites. bushbuck). All tsetse fly species have a long probe, or proboscis, extending horizontally from the base of their head. The parasites range in size from 14 to 33 μm. During the hottest part of the day (visually early to mid-afternoon), the true resting sites are lowest down on tree trunks, and on the underside of shaded, fallen logs. 2) This metacylic stage quickly gives way to a blood-borne stage that begins a series of binary fission divisions at the site of inoculation. Sleeping sickness … For centuries, tsetse have been one of the greatest factors affecting the course of economic and social development in Africa. 1) Infection of a human host occurs when a tsetse fly bites a human and transmits from its salivary glands the metacylic stage (the infective state) of the trypanosome. The flies resemble normal house flies, but can be identified by two distinguishing characteristics. Trypanosomosis in animals severely affects their productivity in several ways and if left untreated is often fatal. At copier times of the day, and in cooler seasons, the flies rest higher up tree trunks, and on the underside of branches. Tsetse fly habitat and land cover: an analysis at continental level TseTse habiTaTs A habitat is the place where a particular species lives and grows. All of the 31 known species and subspecies are capable of transmitting the trypanosome parasites that cause human sleeping sickness and disease in domestic animals that is known as nagana. It is essentially the biophysical environment that surrounds, influences and is utilized by a species population. 186 CHAPTER 2 • TSETSE FLIES can remove flies from an area much larger than the zone of immediate attraction. Tsetse flies feed on the blood of vertebrate animals (including humans) and in doing so, transmit the sleeping sickness parasite from infected animals to uninfected ones.