African sleeping sickness, also known as trypanosomiasis and human African trypanosomiasis (HAT), is a parasitic infection carried by tsetse, also known as tsetse flies.

There are two versions of the condition, each native to different regions of sub-Saharan Africa and caused by slightly different parasites.

According to the Centers for Disease Control and Prevention (CDC), both strains are fatal if their infections aren’t treated promptly.

Medical emergency

African sleeping sickness affects a lot fewer people than it did just a decade or two ago, but it’s still potentially dangerous to a large portion of the world’s population.

Read on to learn more about how African sleeping sickness is transmitted, what the symptoms are, and what to do if you think you have the infection.

African sleeping sickness can be difficult to diagnose in the first stage when symptoms are relatively common and can mimic other, less serious conditions. They can include:

The second stage comes when parasites move from the blood to the brain and start to cause more serious neurological symptoms, like:

  • insomnia
  • daytime sleepiness
  • loss of motor skills
  • confusion
  • hallucinations
  • behavioral changes
  • seizures
  • progressive drowsiness, sometimes leading to a coma

The parasite that causes African sleeping sickness is native to 36 countries in sub-Saharan Africa, which are home to 65 million people. The tsetse fly thrives in rural areas, many of which lack adequate medical care, fresh water, and sanitation.

People who live near or visit the grasslands or forests in these areas — such as hunters, shepherds, and tourists — and have been bitten by tsetse flies are most at risk of encountering the parasite. Cattle often carry the infection.

International efforts have been successful recently in containing African sleeping sickness. The World Health Organization reported only 100 cases of the Eastern version and 600 cases of the Western variety in 2020. About 70% of cases that year were in the Democratic Republic of Congo.

Only 40 Americans have developed African sleeping sickness since 1967.

It’s very important to catch African sleeping sickness before it progresses to the second stage. The initial symptoms can mimic those of less serious diseases, making diagnosis tricky.

If you live in or travel to any of the affected countries, have tsetse fly bites, and experience any of the symptoms listed above, seek treatment immediately. This is especially important if you experience any of the more severe symptoms associated with the second stage of African sleeping sickness.

A non-healing skin ulcer with swollen glands nearby should prompt a visit to a doctor right away.

Blood tests are available for West African sleeping sickness. Sometimes, more invasive tests like an extraction of lymph fluid or a lumbar puncture (spinal tap) may be necessary.

Here are some frequently asked questions about African sleeping sickness.

What causes African sleeping sickness (Trypanosomiasis)?

African sleeping sickness is caused by an infection from the parasite Trypanosoma brucei. The invader first targets the blood, lymph nodes, and fatty tissues in the body.

The condition becomes especially dangerous when the parasite crosses over into the central nervous system. This eventually causes major disruptions to both voluntary and involuntary body functions.

How many types of African sleeping sickness are there?

There are two types of African sleeping sickness. The parasite Trypanosoma brucei gambiense causes the far more common Western form, and its cousin Trypanosoma brucei rhodesiense is responsible for the Eastern version. All 40 cases that have made their way to the United States were the East African type.

West African sleeping sickness usually takes from 300 to 500 days to move from stage 1 to stage 2. East African sleeping sickness develops much more rapidly, in 21 to 60 days, but it’s only responsible for 3% of the world’s current cases.

The same economic and geographic issues that make diagnosis and treatment so difficult also cause many cases to go unreported.

How is African sleeping sickness spread?

Most people get African sleeping sickness after being bitten by an infected tsetse fly. In rare cases, the condition has been transmitted from mother to child, through sexual contact, or in a laboratory setting.

Is African sleeping sickness a serious condition?

While the medical community has made progress in recent years, African sleeping sickness is still a very dangerous and potentially fatal disease. The Institute for Health Metrics and Evaluation reported 1,360 deaths in 2019, a 77% drop since 2010.

How is African sleeping sickness treated?

The treatment for African sleeping sickness varies depending on what stage the person with the condition is in and whether they have the Eastern or Western variety.

The drug pentamidine is used to treat the first stage of West African sleeping sickness, and suramin is used for the early stages of East African sleeping sickness. Only pentamidine is commercially available in the United States as of now, although other drugs can be used for research purposes.

Older treatments for the second stage, like melarsoprol and eflornithine, have been mostly abandoned in favor of a combination of eflornithine and nifurtimox, known as NECT. It was first used in 2009.

The oral drug fexinidazole is another promising newer treatment for African sleeping sickness. It’s effective in both stages and was approved for use for West African sleeping sickness in 2019. It’s currently in trials for use against the Eastern version as well.

Global healthcare providers have succeeded in recent years in fighting the spread of African sleeping sickness. The number of worldwide cases dropped from more than 30,000 in 1998 to around 700 in 2020.

International health organizations still face geographic and economic challenges in diagnosing and treating the rare and fatal disease, but they’ve made significant progress.