gambiense

Gambiense refers to Trypanosoma brucei gambiense, a subspecies of the protozoan parasite Trypanosoma brucei. It is the principal cause of the gambiense form of human African trypanosomiasis (HAT), or sleeping sickness. Transmission occurs through bites of infected tsetse flies (Glossina), with the disease concentrated in West and Central Africa.

Biology and lifecycle: It is a single-celled, flagellated parasite that circulates in blood and lymph, and may invade the CNS in later stages, cycling between humans and tsetse vectors.

Reservoirs and geography: Humans are the main reservoir, though some animals can harbor the parasite in certain regions. Transmission is focal to rural, riverine areas where tsetse flies are common.

Clinical features: The disease progresses slowly. Stage 1 includes fever and lymphadenopathy; stage 2 includes sleep disturbances, cognitive changes, and motor symptoms.

Diagnosis and staging: Parasites may be detected in blood, lymph node aspirates, or cerebrospinal fluid, and screening is commonly done with the card agglutination test for trypanosomiasis (CATT). Staging relies on CSF analysis to assess CNS involvement.

Treatment: Stage 1 is treated with pentamidine. Stage 2 can be treated with NECT or eflornithine-based regimens; oral fexinidazole is available for eligible gambiense HAT cases. Treatment should be delivered in specialized centers under current guidelines.

Control and prognosis: Control combines active case finding, vector management, and surveillance. Timely treatment yields good outcomes; late-stage disease can cause lasting neurological damage. Elimination of gambiense HAT as a public health problem remains a global goal.