Active transmission of Trypanosoma brucei gambiense Dutton, 1902 sleeping sickness in Abraka, Delta State, Nigeria

Abstract

Active surveillance of Human African trypanosomiasis (HAT) or sleeping sickness was undertaken in 3 agrarian villages in Ethiope East Local Government Area of Delta State, Nigeria. Card Agglutination Trypanosomiasis Test (CATT) was used qualitatively for mass screening with undiluted fresh whole blood (WB) and quantitatively for diagnosis in serum dilution tests. Thereafter, palpation for enlarged cervical lymph gland (ECLG) was followed by parasitological examination of aspirate using wet film, haematocrit centrifugation technique (HCT) and mini-anion exchange centrifugation technique (mAECT). Only one
confirmed case of sleeping sickness was diagnosed out of the 491 samples screened. The results showed 43 (9.8%)
serological positive cases in WB/ CATT test. 12 (27.9%) suspected cases that reacted at &lt1/4 titre in serum dilution test were highly suspected serological positive but parasitological negative cases. The study indicates that there is ongoing active transmission of Gambian type sleeping sickness in Abraka focus of Nigeria. The highly suspected cases will be followed up. Many cases might have gone undetected and more villages within the same focus were not covered. Moreover, a large-scale multi-disciplinary disease surveillance, vector and animal reservoir studies are required to determine the true situation of HAT in this focus.

KEY-WORDS: Transmission, Gambian Trypanosomiasis, Screening, Blood, Serum, Diagnosis.