Tsetse flies are generally classed as insects of medical and veterinary importance, but qualify for consideration by this group by virtue of their indirect influence on agricultural development in Africa and their possible control by the application of insecticides from aircraft.

Tsetse flies are confined to the African continent and a few small off-shore islands. They are widely distributed between 14°N and 29°S wherever the environment is suitable; and are absent from N. Africa, the Sahara, the Red Sea Zone and the Somalias, and the highlands of Ethiopia, and from the Union of South Africa, except Zululand.