Definition of Sleeping sickness:

Sleeping sickness is infection with germs carried by certain flies. It results in swelling of the brain.

Causes, incidence, and risk factors:

Sleeping sickness is caused by two germs, Trypanosoma brucei rhodesiense and Trypanosomoa brucei gambiense. The more severe form of the illness is caused by T. rhodesiense.

Tsetse flies carry the infection. When an infected fly bites you, the infection spreads through your blood.

Risk factors include living in parts of Africa where the disease is found and being bitten by tsetse flies. The disease is very rare in the United States, and is only found in travelers who have visited or lived in Africa.

Symptoms:

General symptoms include:

• Anxiety
• Drowsiness during the day
• Fever
• Headache
• Insomnia at night
• Mood changes
• Sleepiness (may be uncontrollable)
• Sweating
• Swollen lymph nodes all over the body
• Swollen, red, painful nodule at site of fly bite
• Weakness

Signs and tests:

A physical examination may show signs of inflammation of the brain and its covering, the meninges (meningoencephalitis).

Tests include the following:

• Blood smear
• Cerebrospinal fluid tests
• Complete blood count (CBC)
• Lymph node aspiration

Most antibody and antigen tests are not very helpful because they cannot tell the difference between current and past infection. Specific IgM levels in the cerebrospinal fluid may be helpful, however.

Treatment:

Medications used to treat this disorder include:

• Eflornithine (for T. gambiense only)
• Melarsoprol
• Pentamidine
• Suramin (Antrypol)
• Some patients may receive combination therapy

Expectations (prognosis):

Without treatment, death may occur within 6 months from cardiac failure or from T. rhodesiense infection itself. T. gambiense infection causes the classic "sleeping sickness" disease and gets worse more quickly, often over a few weeks. Both diseases should be treated immediately.

Complications:

Complications include injury related to falling asleep while driving or performing other activities, and progressive damage to the nervous system. Sleep becomes uncontrollable as the disease gets worse, and eventually leads to coma.

Inflammation of the heart (myocarditis) may develop.

Calling your health care provider:

Call your health care provider if you have symptoms of this disorder. It is important to begin treatment as soon as possible.

Prevention:

Pentamidine injections protect against T. gambiense, but not against T. rhodesiense. Because it is a toxic drug, usuing it for prevention is not recommended.

Insect control measures can help prevent the spread of sleeping sickness in high-risk areas.