African sleeping sickness: Also called African trypanosomiasis, a systemic disease caused by the parasite Trypanosoma brucei that is transmitted by the bite of the tsetse fly, a gray-brown insect about the size of a honeybee. African trypanosomiasis is confined to tropical Africa from north of South Africa to south of Algeria, Libya, and Egypt. Tsetse flies inhabit rural areas only, living in the woodland and thickets of the savannah and the dense vegetation along streams. Although infection of international travelers was considered rare, the number of cases in travelers, primarily to East African game parks, has increased in recent years. Travelers visiting game parks and remote areas should take precautions. Travelers to urban areas are not at risk.
The signs and symptoms of the infection are initially nonspecific (high fever, rash, edema, or swollen glands) but the disease progresses to encephalitis and meningitis. Symptoms generally appear within 1 to 3 weeks of infection. Untreated cases are eventually fatal. People who have had tsetse fly bites or become ill with high fever or other manifestations of African trypanosomiasis are advised to seek early medical attention. The infection can usually be cured by an appropriate course of anti-trypanosomal therapy. Pentamidine isethionate and suramin are the drugs of choice to treat the hemolymphatic stage of West and East African trypanosomiasis, respectively. Melarsoprol is the drug of choice for late disease with central nervous system involvement.
No vaccine is available to prevent this disease. Tsetse flies are attracted to moving vehicles and dark, contrasting colors. They are not affected by insect repellents and can bite through lightweight clothing. Areas of heavy infestation tend to be sporadically distributed and are usually well known to local residents. Avoidance of such areas is the best means of protection. Travelers at risk should be advised to wear clothing of wrist and ankle length that is made of medium-weight fabric in neutral colors that blend with the background environment.