About Sleeping Sickness

Overview

Sleeping sickness (i.e., human African trypanosomiasis or HAT) is caused by the parasite Trypanosoma brucei. A parasite is an organism (a living thing) that lives on or inside another organism. Sleeping sickness spreads through the bite of a tsetse fly (Glossina species), found only in rural, sub-Saharan Africa. The disease causes death if left untreated. There are two types of sleeping sickness. Each one is named for the region in Africa where it was historically found.

Types

There are two types of sleeping sickness:

West African sleeping sickness

• Spread by bites from a tsetse fly carrying the parasite T. b. gambiense.
• Disease is slow to progress (a few months to a year or more after exposure).
• Found in rural parts of Central and West Africa.
• The World Health Organization (WHO) publishes the number of West African sleeping sickness cases reported each year to its website.

East African sleeping sickness

• Spread by bites from a tsetse fly carrying the parasite T. b. rhodesiense.
• Disease progresses in severity very quickly (one to several weeks after exposure).
• Found in rural parts of Eastern and Southern Africa and less commonly reported than West African sleeping sickness.
• The World Health Organization (WHO) publishes the number of East African sleeping sickness cases reported each year to its website.

Signs and symptoms

Sleeping sickness occurs in two stages. The first stage typically causes mild, flu-like symptoms. The second stage causes more severe symptoms that affect your brain and central nervous system. Symptoms of each stage take longer to appear in West African sleeping sickness.

If you recently traveled to east or west Africa and were bitten by a tsetse fly, you could have sleeping sickness. Some people who have sleeping sickness develop a red sore, called a chancre, within two days to two weeks of an infected tsetse fly bite but chancres are not always present or noticed.

Risk factors

Sleeping sickness affects people in rural areas of African countries. Travelers to urban areas in those countries are at low risk.

People at higher risk include:

• Hunters
• Villagers with infected cattle herds
• Tourists visiting and others working in game parks

Tsetse flies that spread sleeping sickness live only in some African countries. Most flies in these rural areas are not carrying the parasite that causes sleeping sickness. However, the more often you are bitten, the more you are at risk of infection.

You cannot contract the disease in the U.S.

How it spreads

You can get sleeping sickness from the bite of an infective tsetse fly.

Occasionally, a pregnant women may pass the parasite Trypanosoma brucei to her unborn baby.

Although rare and not well documented, the parasite may also spread through

• Sexual contact
• Blood transfusion
• Organ transplantation
• Accidental laboratory exposure

Prevention

There is no vaccine or drug available to prevent sleeping sickness.

The best way to prevent infection is to prevent bites from the tsetse fly:

• Wear protective, neutral-colored clothing, including long pants, long-sleeved shirts, and socks.
• Inspect vehicles for tsetse flies before entering.
• Avoid bushes.
• Use insect repellant.

Read more: Prevent Sleeping Sickness

Diagnosis

There are several tests that can diagnose sleeping sickness. Talk with your healthcare provider right away if you have traveled to rural areas of the countries in Africa where sleeping sickness spreads and are experiencing any of the symptoms or think you may have sleeping sickness.

Treatment

If diagnosed with sleeping sickness, start medical treatment as soon as possible. Your laboratory results should guide your treatment.

Hospitalization is usually necessary for treatment. Follow-up care may require lumbar puncture (spinal tap) every six months or sooner, if symptoms return, for two years.