Human African trypanosomiasis (sleeping sickness): new endemic foci in Bendel State, Nigeria.

Human African Trypanosomiasis (Sleeping Sickness) surveys were conducted in five communities in Ethiope and Ndokwa Local Government Areas of Bendel State, Southern Nigeria. Of 670 individuals screened for the disease with the Card Agglutination Test for Trypanosomiasis (CATT), 84 (12.53%) were positive while 45 (6.72%) had traces of antibodies against Trypanosoma brucei gambiense in their blood. Trypanosomes were also demonstrated in the gland juices of 22 individuals following gland punctures and microscopic examination of the aspirates. Analysis of 86 serum samples obtained from the blood randomly collected from individuals in the localities, using the qualitative methods of CATT and Cellognost (Indirect Haemagglutination - IHA) showed that 58 (67.44%) and 57 (66.28%), were seropositive for sleeping sickness, respectively. Further titration of 72 of these serum samples using the Cellognost quantitative method showed 50 samples with antibody titres above 1:20. The clinical manifestations of sleeping sickness recorded in positive individuals included cervical lymphadenopathy, somnolence, psychosis, unsteady gait and tremors, and reproductive abnormalities reflected by secondary amenorrhea and poor obstetric histories. Our observations indicate that the parts of Bendel State surveyed are probably endemic foci of sleeping sickness hitherto unreported. The effectiveness of the CATT in mass screening of populations at risk from the disease is also highlighted.