Wuchereria bancrofti infection in rural tropical guinea - savannah communities: Rapid epidemiological assessment using immunochromatographic card test and prevalence of hydrocoele

摘要

Lymphatic filariasis (LF) caused by the nematode Wuchereria bancrofti is a major public health concern in endemic communities worldwide. Among tropical diseases it is second to malaria in terms of disability adjusted life years. The Nigerian LF elimination programme has been slated for 2015. Currently, there is paucity of published data on the problem in rural Ebonyi State. This survey was conducted in six rural communities of southwestern Ebonyi State to assess its prevalence among the population and provide baseline data for incorporation into the national LF elimination programme. Immunochromatographic card test (ICT) for detecting circulating filarial antigen (CFA) using whole blood and overt clinical manifestations (lymphoedema and hydrocoele) were used as epidemiological tools. All the studied communities were endemic for active bancroftian filariasis. Of the 600 randomly selected subjects aged 10 years, an overall prevalence of 23.50% was established (range, 17.00 - 30.00%). Overall, the antigenaemic prevalence was similar; there was a trend of slightly higher prevalence in males (24.34%) than females (22.39%). The between-gender prevalence difference was not statistically significant ( χ 2 = 8.16, df = 1, p = 0.05) based on CFA positivity. Antigenaemia prevalence was age-dependent, increased exponentially and peaked at 20.57% in subjects in the 40-49 years age category. Lymphoedema and hydrocoele attributable to W. bancrofti were observed in 4.05% of subjects examined. Generally, hydrocoele was observed in 1.69% males, whereas lymphoedema was presented by 2.36% (1.35% females; 1.01% males) of studied population. None of the male subjects had both the two clinical features. Results of this study showed that W. bancrofti infection is widespread in southwestern Ebonyi State, Nigeria, and is a major health issue. There is a need for mass mobilization, mass education and community involvement in sustained intervention programme toward lymphatic filariasis elimination.