Schistosomiasis and intestinal parasites in rural villages in southwest Nigeria: an indication for expanded programme on drug distribution and integrated control programme in Nigeria.

A cross sectional survey of schistosomiasis, intestinal parasite infections and pattern of schistosomiasis transmission was undertaken in four rural villages around the Erinle dam, Nigeria. The prevalence of Schistosoma haematobium ranged from 10% to 60%. 30% of infected school children excreted over 50 eggs/10 ml urine and high rates of haematuria, proteinuria, leucocyturia and nitrites in urine were observed in infected children and the villagers. Prevalence of infection with S. mansoni ranged from 11.4% to 36.8%. Intensity of infection based on geometric mean eggs/gram of faeces ranged between 100 and 545.7 eggs/g. Malacological surveys showed that Biomphalaria pfeifferi was the predominant potential snail hosts recovered at all the contact sites. Higher infections with schistosome parasites were also recorded for B. pfeifferi than Bulinus globosus. The pattern of transmission of schistosomiasis by the snails is consistent and makes incorporation of community-based focal application of a molluscicide such as Tetrapleura tetraptera in integrated control of schistosomiasis feasible in the area. Prevalence and intensity with Ascaris lumbricoides was high. The highest prevalence was 68.9% while the highest intensity of infection was 2,440.9 eggs/gram of faeces. Multiple infections occured with various combinations of Ascaris lumbricoides, hookworm, S. haematobium, Fasciola gigantica, S. mansoni, and Entamoeba histolytica (as double, triple or quadruple infections). The results suggest an integrated approach to the control of schistosomiasis and intestinal parasites in this part of the country.