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

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 (χ² = 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.

Prevalence and transmission dynamics of Schistosoma haematobium infection in a rural community of southwestern Ebonyi State, Nigeria.

A twelve-month epidemio-ecological study on the prevalence, infection intensity, water contact and vector aspects of urinary schistosomiasis was conducted in a rural community of south-west Ebonyi State, Nigeria, using standard procedures, and involving 894 individuals (527, 58.9% males; and 367, 41.1% females). An overall community prevalence (15.3%) was established with more males (20.7%) than females (7.6%) being significantly positive for both micro-and macro-haematuria (χ² = 0.806; df = 1, p < 0.05). Intensity of infection was generally of the light category (< 100 eggs/10 ml urine) with more infected males (n = 95, 87.2%) than infected females (n = 15, 53.6%). Correlation analysis showed no linear relationship between prevalence and intensity of infection. Individuals aged 16-20 years dominated interschool/intervillage infection profile (range 13.2-50%) while participants in 6-10 years age bracket recorded the lowest infection rates (range 2.8-5.0%). Age-related difference in prevalence was not significant (χ² = 1.80; df = 2, p > 0.05). A total of 2877 ova of Schistosoma haematobium were recovered providing an overall mean egg burden of 21 ± 7 eggs/10 ml urine per infected person. Age-related infection intensity was similarly of the light category involving 80.3% of infected persons. Bulinus globosus (n = 308) was identified as the vector of the parasite with 20.1% snails found to be shedding cercariae. Monthly and seasonal infection rates in snails were season-dependent and peaking in May (35.5%). Participants aged 13-15 years accounted for 25.1% of total water contacts (n = 9938) whereas individuals aged 6-9 years accounted for only 9.6% contacts. The most performed water contact activity was bathing (33.3%), followed by washing of clothes (25.7%). Correlation analysis indicated that village of residence, age and cumulative water contacts were significant correlates of possible S. haematobium infection.