Sleeping sickness

"Sleeping sickness" is also another name for Narcolepsy.

Trypanosomes in a blood smear

Sleeping sickness, or African trypanosomiasis, is an infectious disease. It is caused by parasites from the species Trypanosoma brucei.

People get African trypanosomiasis from the tsetse fly. Because of this, it is most common in certain areas of Africa, especially Sub-Saharan Africa, where the tsetse fly lives. Researchers say that about 70 million people, in 36 countries, are at a high risk for getting sleeping sickness.^[1] As of 2010, sleeping sickness had caused around 9,000 deaths per year (compared to 34,000 in 1990).^[2]

In 2013, about 30,000 people had African trypanosomiasis. Also, about 7,000 more people were getting the disease every year.^[3] More than 80% of these people in the Democratic Republic of the Congo.^[3]

Medications can treat African trypanosomiasis. The treatment is usually done in a hospital, because the drugs have many side effects. For sleeping sickness that was not treated early, the medications used for treatment are based on arsenic, a poison. These medications are dangerous, and about 5% of people die from taking them.

The best way to protect against African trypanosomiasis is to protect against insect bites.

Signs and symptoms

The signs and symptoms of African trypanosomiasis happen in two stages.

The hemolyphatic phase

Common symptoms in this stage include:

A fever that comes and goes
Headaches
Pain in the joints
Itching
Lymphadenopathy: As the parasite gets into the lymphatic system, the body's lymph nodes swell, sometimes to very large sizes
A chancre (red sore) where the person was bitten by the tsetse fly (sometimes)

If African trypanosomiasis is not treated at this point, the parasite will also get into the circulatory system and defeat the body's natural defenses. If this happens, the person can have:

The neurological phase

This phase begins when the parasite invades the central nervous system by passing through the blood–brain barrier.

In this stage, one of the most common symptoms is trouble sleeping. This is where the name "sleeping sickness" comes from. People in this stage often cannot sleep normally, and may be up all night and then sleep during the day..^[4]

Other symptoms in this stage can include:^[5]

Mental confusion
Tremor
Muscle weakness
Weakness or paralysis of an arm or leg
Movements that the person cannot control, like a person with Parkinson syndrome
Psychosis
Feeling easily annoyed or being aggressive

Without treatment, a person with African sleeping sickness will go into a coma; (thus the name) all their important organs will stop working; and they will die.^[6]Damage caused in the neurological phase cannot be fixed.^[6]

Sleeping Sickness Media

The life cycle of the Trypanosoma brucei parasites
Drawing of a tsetse fly from 1880
Two areas from a blood smear from a person with African trypanosomiasis, thin blood smear stained with Giemsa: typical trypomastigote stages (the only stages found in people), with a posterior kinetoplast, a centrally located nucleus, an undulating membrane, and an anterior flagellum. The two Trypanosoma brucei subspecies that cause human trypanosomiasis, T. b. gambiense and T.
Capture devices for tsetse flies, on shore and on a boat in Africa. Efforts to prevent sleeping sickness.
Deaths per 100,000 population due to African trypanosomiasis by country in 2002
In 1903, David Bruce recognized the tsetse fly as the arthropod vector.
Typical fine-spotted pink rash of acute African trypanosomiasis on the skin of the abdomen ("trypanid rash")
Sleeping Sickness Commission photos Wellcome L0049104