Tsetse Fly

The tsetse fly’s painful bite can transmit African trypanosomiasis or ‘sleeping sickness’. The fly is found only in Africa between latitudes 15° north and 20° south, especially in remote rural regions. Active during the day, the tsetse fly is attracted to large moving objects and the colour blue. An increase in the number of cases has been noted in recent years notably in the southern Sudan. The parasites are known as trypanosomes hence the medical term for the infection is TRYPANOSOMIASIS.

There are two forms of the disease each caused by a different sub-species of the parasite Trypanasoma brucei. One form (caused by the rhodesiense sub-species and therefore called the Rhodesian or eastern form) is an acute illness lasting up to a few weeks and occurs in eastern and southern regions. The other form, known as western or Gambian form, occurrs in western and central Africa, producing a long lasting, chronic disease which causes symptoms over a period of many years. If untreated most patients with either form of the disease will die or be left with irreversible brain damage.


Seek medical help if you notice a boil-like sore a few days after being bitten, especially if you have also developed a fever.


When visiting endemic areas, travellers should wear long-sleeved shirts and long pants, avoid bright-coloured clothing, and keep car windows closed. Permethrin and DEET have some value but are not always effective against the tsetse fly. There is no vaccine or preventive drug available for this illness.

The tsetse fly in Africa is attracted to bright blue. The safest colours to wear are beige or khaki.