Sleeping sickness

Sleeping sickness, also known as African trypanosomiasis, is a vector-borne parasitic disease. It is caused by infection with protozoan parasites belonging to the genus Trypanosoma. They are transmitted to humans by the bite of an infected tsetse fly (Glossina species), which is found only in rural Africa. Although the infection is not found in the United States, historically, it has been a serious public health problem in some regions of sub-Saharan Africa.

Etiology

Sleeping sickness is caused by two types of parasitic protozoa, Trypanosoma brucei gambiense (T.b. gambiense) and Trypanosoma brucei rhodesiense (T.b. rhodesiense). T.b. gambiense accounts for over 98% of reported cases, causing a chronic infection that can last several years. T.b. rhodesiense causes an acute infection, which can lead to death within weeks or months without treatment.

Transmission

The disease is transmitted through the bite of an infected tsetse fly. The flies acquire the parasite when they feed on the blood of an infected person or animal. In addition to tsetse flies, the disease can also be transmitted from mother to child during pregnancy or childbirth, and through blood transfusion or organ transplantation.

Symptoms

The symptoms of sleeping sickness are divided into two stages. The first stage, known as the hemolymphatic phase, is characterized by fever, headaches, joint pains, and itching. The second stage, known as the neurological phase, is marked by changes in behavior, confusion, sensory disturbances, poor coordination, and disruption of the sleep cycle, which gives the disease its name.

Diagnosis

Diagnosis of sleeping sickness is made by identifying the trypanosomes in a blood sample or in fluid or tissue from lymph nodes, or by detecting antibodies against the parasite in the blood.

Treatment

Treatment for sleeping sickness is dependent on the species of trypanosome causing the infection and the stage of the disease. Drugs used for treatment include suramin, pentamidine, melarsoprol, and eflornithine.

Prevention

Prevention strategies for sleeping sickness include controlling the tsetse fly population and using protective clothing and insect repellent to avoid bites.

See also

• Chagas disease
• Leishmaniasis
• Malaria