sleeping sickness
an infection found only in tropical Africa; it is caused by parasitic protozoans of the genus Trypanosoma (T. gambiense and T. rhodesiense), which are transmitted by the bite of infected tsetse flies. Initial symptoms include fever, headaches, sweating, and swollen lymph nodes, progressing—upon inflammation of the brain and its protective membranes (see meninges)—to lethargy, excessive sleepiness (see hypersomnia), and confusion. If untreated, sleeping sickness can result in coma and eventually death. Also called African trypanosomiasis.