Human African trypanosomiasis in endemic focus of Abraka, Nigeria.

Objective: To investigated the prevalence of human African trypanosomiasis (HAT), a neglected tropical disease caused by Trypanosoma brucei gambiens in an endemic focus of Nigeria, as it relates to age, sex and occupational differences. Methods: A total of 474 human subjects were screened using card agglutination test for trypanosomiasis kit. Positive samples were further investigated for parasite positivity in blood/serum and cerebrospinal fluid (CSF). Results: Of the 474 screened, 44(9.3%) were seropositive with seroprevalence of 22(9.6%) in Urhouka, 14(9.5%) in Umeghe and 8(7.9%) for Ugonu. The number of seropositives, observed for weakly, moderately and strongly positives for the three communities were 4, 7 and 11 in Urhouka, 4, 5 and 5 in Umeghe and 3, 2 and 3 in Ugonu respectively. Among the 16 volunteers with detected parasite in their blood, 4 of them were weakly positive, 5 of them were moderately positive and 7 of them strongly positive. 4 volunteers from Urhouka community were found parasites in their CSF and they were all strongly positive. The difference between the seroprevalence of males and females was not statistically significant (OR=1.14, 95% CI=0.37-3.4, P＞0.05). The prevalence difference between age group 21-30 years old and the youngest and oldest age groups was statistically significant (OR=3.5, 95% CI=1.08-12.57, P＜0.05) but not significant for other age categories (P＞0.05). It was observed that farmers had significantly higher prevalence of HAT infection as well as greater risk of Trypanosoma brucei gambiense infection than inhabitants with other occupations (OR=3.25, 95% CI=0.99-1l.79, P＜0.05). Conclusions: Human activities such as farming and visits to the river have been identified as major risk factors to HAT. Also the breakdown of HAT control program has been advanced for the rise in HAT in Abraka, an endemic focus in Nigeria.