African Sleeping Sickness

What is African sleeping sickness?

African sleeping sickness (African trypanosomiasis) is a disease caused by a parasite. It is passed on by the bite of the infected tsetse fly.

What causes African sleeping sickness?

There are 2 types of the disease. They are named for the areas of Africa where they are found. West African sleeping sickness is caused by the parasite Trypanosoma brucei gambiense. This long-term (chronic) infection can last for years. East African sleeping sickness is caused by Trypanosoma brucei rhodesiense. It’s a short-term (acute) illness that may last several weeks to months.

People from the U.S. who travel to Africa are rarely infected. On average, 1 U.S. citizen is infected every year. The person is typically infected in East African game parks.

Who is at risk for African sleeping sickness?

The only people at risk for African sleeping sickness are those who travel to Africa. That’s where the tsetse fly is found. The parasites that cause the disease are passed on only by the tsetse fly.

The tsetse flies live only in rural areas. They live in woodland thickets of the savanna and dense vegetation along streams. Visitors to cities and other urban areas are usually not at risk. The disease is found mainly in tropical Africa. The greatest risk of getting it is in:

  • Angola 
  • Central African Republic
  • Chad
  • Congo
  • Democratic Republic of Congo
  • Malawi
  • Tanzania 
  • Sudan
  • Uganda 
  • Zambia

What are the symptoms of African sleeping sickness?

Tsetse fly bites can be quite painful. Travelers often recall being bitten. A painful sore often shows up at the site of the bite within a week or so. It’s called a chancre.

Each person may have slightly different symptoms. But symptoms tend to happen within 1 to 4 weeks of infection. At first, they may include fever, skin lesions, rash, swelling, or swollen lymph nodes on the back of the neck. After many weeks, the infection may become meningoencephalitis. This is an infection of the brain and the fluid surrounding the brain and spinal cord. As the illness gets worse, symptoms may include:

  • Severe headache
  • Personality change
  • Weight loss
  • Irritability
  • Loss of concentration
  • Progressive confusion
  • Slurred speech
  • Seizures
  • Difficulty walking and talking
  • Sleeping for long periods of the day
  • Insomnia at night

If left untreated, death will occur within several weeks to months. The symptoms of African sleeping sickness may look like other health problems. Always see your healthcare provider for a diagnosis.

How is African sleeping sickness diagnosed?

See a healthcare provider as soon as possible if you think you are infected. Tests can find the parasite. These tests may include blood samples and a spinal tap (lumbar puncture). Your provider may also take a sample of chancre fluid or tissue, or fluid from swollen lymph nodes.

How is African sleeping sickness treated?

Treatment will depend on your symptoms, age, and general health. It will also depend on how severe the condition is.

Medicine is available to treat the disease. You will need to stay in the hospital. After you go home, you will need follow-up exams for about 2 years. These will include a spinal tap. Because this infection is so rare, your healthcare provider may talk with an infectious disease or tropical medicine specialist.

What are possible complications of African sleeping sickness?

If the disease is not treated, the symptoms can worsen to a severe illness. Death will occur.

What can I do to prevent African sleeping sickness?

No vaccine or medicine can prevent African sleeping sickness. But you can prevent being bitten by tsetse flies. Experts recommend the following:

  • Wear protective clothing, such as long-sleeved shirts and pants. Tsetse flies can bite through material, so clothing should be made of thick fabric.
  • Wear khaki, olive, or other neutral-colored clothing. Tsetse flies are attracted to bright and dark contrasting colors.
  • Use bed nets when sleeping.
  • Look inside vehicles for tsetse flies before getting into them.
  • Do not ride in the back of jeeps, pickup trucks, or other open vehicles. Tsetse flies are attracted to the dust created by moving vehicles and animals.
  • Stay away from bushes. During the hottest part of the day, the tsetse fly will rest in bushes. But they will bite if disturbed.

Living with African sleeping sickness

Be sure to follow your healthcare provider’s directions. You will need to be checked out periodically for at least a couple years.

When should I call my healthcare provider?

If you have a fever, rash, or chancre (ulceration of the skin) after returning from areas in Africa where you may have been bitten by a tsetse fly, contact your healthcare provider.

Key points about African sleeping sickness

  • African sleeping sickness is a disease caused by a parasite. It is passed on by the bite of the infected tsetse fly.
  • The only risk factor is travel to parts of Africa where the tsetse fly is found.
  • The only way to prevent the disease is to prevent insect bites.
  • Medicine is available to treat it.

Next steps

Tips to help you get the most from a visit to your healthcare provider:

  • Know the reason for your visit and what you want to happen.
  • Before your visit, write down questions you want answered.
  • Bring someone with you to help you ask questions and remember what your provider tells you.
  • At the visit, write down the name of a new diagnosis and any new medicines, treatments, or tests. Also write down any new instructions your provider gives you.
  • Know why a new medicine or treatment is prescribed and how it will help you. Also know what the side effects are.
  • Ask if your condition can be treated in other ways.
  • Know why a test or procedure is recommended and what the results could mean.
  • Know what to expect if you do not take the medicine or have the test or procedure.
  • If you have a follow-up appointment, write down the date, time, and purpose for that visit.
  • Know how you can contact your provider if you have questions.
Medical Reviewer: Barry Zingman MD
Medical Reviewer: Amy Finke RN BSN
Medical Reviewer: L Renee Watson MSN RN
© 2000-2022 The StayWell Company, LLC. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.
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