Gambian Sleeping Sickness - West African Trypanosomiasis
What is African trypanosomiasis?
There are two types of African trypanosomiasis (also called sleeping sickness); each named for the region of Africa in which it is found. Individuals can become infected with West African trypanosomiasis if they receive a bite from an infected tsetse fly, found only in Africa.West African trypanosomiasis, also called Gambian sleeping sickness, is caused by a parasite called Trypanosoma brucei gambiense (tri-PAN-o-SO-ma BREW-see-eye GAM-be-ense) carried by the tsetse fly. Worldwide, approximately 40,000 new cases of both East and West African trypanosomiasis are reported to the World Health Organization each year. However, the majority of cases are not reported due to a lack of infrastructure and it is likely that there are more than 100,000 new cases annually. Few cases of West African trypanosomiasis have been reported in the United States.
How can I get West African trypanosomiasis?
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.
Is West African trypanosomiasis a serious illness?
Yes. West African trypanosomiasis is fatal if it is not treated.
Where can I contract West African trypanosomiasis?
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.
What are the symptoms of 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.
How soon after infection will I have symptoms of West African trypanosomiasis?
Symptoms occur within months to years after getting an infected tsetse fly bite.
What should I do if I think I have African trypanosomiasis?
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.
Is treatment available for West African trypanosomiasis?
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.
Who is at risk for contracting West African trypanosomiasis?
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 travelling and spending long periods of time in rural areas of Western and Central Africa.
Can I take medication to prevent West African trypanosomiasis?
There is neither a vaccine nor recommended drug available to prevent West African trypanosomiasis.
How can I prevent African trypanosomiasis and other insect bites?
- 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.
- Wear khaki or olive colored clothing. The tsetse fly is attracted to bright colors and very dark colors.
- Use insect repellant. Though insect repellants have not proven effective in preventing tsetse fly bites, they are effective in preventing other insects from biting and causing illness.
- Use bed netting when sleeping.
- Inspect vehicles for tsetse flies before entering.
- 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.
- Avoid bushes. The tsetse fly is less active during the hottest period of the day. It rests in bushes but will bite if disturbed.
For more information:
- McGovern TW, William W, Fitzpatrick JE, et al. Cutaneous manifestations of African trypanosomiasis. Arch Dermatol 1995;131:1178-82.
- Bryan R, Waskin J, Richards F, et al. African trypanosomiasis in American travelers: a 20-year review. Travel Medicine. Steffen R, Lobel HO, Haworth J, Bradley DJ, eds. Berlin: Springer-Verlag, 1989:384-8.
See also East African trypanosomiasis, and American trypanosomiasis (also known as chagas disease).
