African Trypanosomiasis

Medically Reviewed by Nayana Ambardekar, MD on March 12, 2024
Written by WebMD Editorial Contributors
5 min read

There are two types of African trypanosomiasis (also called sleeping sickness); each is named for the region of Africa in which they are found. The disease is caused by parasites named Trypanosoma brucei rhodesiense (tri-PAN-o-SO-ma BREW-see-eye rho-DEE-see-ense) and Trypanosoma brucei gambiense (tri-PAN-o-SO-ma BREW-see-eye GAM-bee-ense), both carried by the tsetse fly. Worldwide, cases have been dropping due to control efforts: The number of reported cases fell under 10,000 in 2009. In 2020, fewer than 700 combined cases were reported, according to the World Health Organization.

An individual will get East African trypanosomiasis if they are bitten by a tsetse fly infected with the Trypanosoma brucei rhodesiense parasite. The tsetse fly is common only to Africa.

An individual gets West African trypanosomiasis through the bite of an infected tsetse fly, found only in Africa. On rare occasions, a pregnant woman may pass the infection to her baby, or an individual may become infected through a blood transfusion or organ transplant.

Yes. If a person fails to receive medical treatment for East African trypanosomiasis, death will occur within several weeks to months. West African trypanosomiasis is fatal if it is not treated.

East African trypanosomiasis is found in parts of Eastern and Southeastern Africa, including Uganda, Kenya, Tanzania, Malawi, Ethiopia, Zaire, Zimbabwe, and Botswana. Areas where infection is spread are largely determined by the location of the infected tsetse fly and wild animal population.

West African trypanosomiasis can be contracted in parts of Western and Central Africa. The tsetse fly lives only in Africa; areas where infection is spread are largely determined by where the infected tsetse fly is found.

East African trypanosomiasis: A bite by the tsetse fly is often painful and can develop into a red sore, also called a chancre (SHAN-ker). Fever, severe headaches, irritability, extreme fatigue, swollen lymph nodes, and aching muscles and joints are common symptoms of sleeping sickness. Some people develop a skin rash. Progressive confusion, personality changes, slurred speech, seizures, and difficulty in walking and talking occur when infection has invaded the central nervous system. If left untreated, infection becomes worse and death will occur within several weeks or months.

West African trypanosomiasis: A bite by the tsetse fly is often painful. Occasionally, within 1 to 2 weeks, the infective bite develops into a red sore, also called a chancre (SHAN-ker). Several weeks to months later, other symptoms of sleeping sickness occur. These include fever, rash, swelling around the eye and hands, severe headaches, extreme fatigue, aching muscles and joints. You may develop swollen lymph nodes on the back of your neck called Winterbottom's sign. Weight loss occurs as the illness progresses. Progressive confusion, personality changes, slurred speech, irritability, loss of concentration, seizures, and difficulty in walking and talking occurs when infection has invaded the central nervous system. These symptoms become worse as the illness progresses. Sleeping for long periods of the day and having insomnia at night is a common symptom. If left untreated, infection becomes worse and death will occur within several months to years after infection.

With East African trypanosomiasis, symptoms begin within 1 to 4 weeks of getting an infected tsetse fly bite.

With West African trypanosomiasis, symptoms occur within weeks or months after getting an infected tsetse fly bite.

If you suspect that you may have East African trypanosomiasis, immediately consult with your health care provider who will order several tests to look for the parasite. Common tests include blood samples, a spinal tap, and skin biopsies, especially if you have a chancre.

If you suspect that you may have West African trypanosomiasis, see your health care provider who will order several tests to look for the parasite. Common tests include blood samples and a spinal tap. Your physician may also take a sample of fluid from swollen lymph nodes.

Medical treatment of East African trypanosomiasis should begin as soon as possible and is based on the infected person’s symptoms and laboratory results. Medication for the treatment of East African trypanosomiasis is available through the CDC. Hospitalization for treatment is necessary. Periodic follow-up exams that include a spinal tap are required for 2 years.

Medication for the treatment of West African trypanosomiasis is available. Hospitalized treatment of West African trypanosomiasis should begin as soon as possible and is based on the infected person’s symptoms and laboratory results. Hospitalization for treatment is necessary. Periodic follow-up exams that include a spinal tap are required for 2 years.

No one is immune from East African trypanosomiasis. Even if you had the disease once, you can get re-infected.

East African trypanosomiasis is usually found in woodland and savannah areas away from human habitation. Tourists, hunters, game wardens, and other persons working or visiting game parks in East and Southeastern Africa are at greatest risk for illness.

Tsetse flies can be found in Western and Central African forests, in areas of thick shrubbery and trees by rivers and waterholes. Risk of infection increases with the number of times a person is bitten by the tsetse fly. Therefore, tourists are not at great risk for contracting West African trypanosomiasis unless they are traveling and spending long periods of time in rural areas of Western and Southeastern Africa.

There is neither a vaccine nor recommended drug available to prevent East or West African trypanosomiasis.

  1. Wear protective clothing, including long-sleeved shirts and pants. The tsetse fly can bite through thin fabrics, so clothing should be made of thick material.
  2. Wear khaki or olive colored clothing. The tsetse fly is attracted to bright colors and very dark colors.
  3. Use insect repellent. Though insect repellants have not proven effective in preventing tsetse fly bites, they are effective in preventing other insects from biting and causing illness.
  4. Use bed netting when sleeping.
  5. Inspect vehicles for tsetse flies before entering.
  6. Do not ride in the back of jeeps, pickup trucks or other open vehicles. The tsetse fly is attracted to the dust that moving vehicles and wild animals create.
  7. Avoid bushes. The tsetse fly is less active during the hottest period of the day. It rests in bushes but will bite if disturbed.

See also American trypanosomiasis (also known as chagas disease).

This fact sheet is for information only and is not meant to be used for self-diagnosis or as a substitute for consultation with a health care provider. If you have any questions about the disease described above or think that you may have a parasitic infection, consult a health care provider.