Spatial distribution and ecology of soil parasites and Schistosoma haematobium infection in Eggua, Nigeria

Objective: This study assessed the risk associated with environmental contamination by parasites in urinary schistosomiasis endemic areas. Methods: Urogenital schistosomiasis surveys were conducted in some rural communities in Yewa North Local Government Area, Ogun State between August 2012 and June 2016. Soil samples were examined for the presence of STH infective stages by microscopy. Geo-coordinates of each soil sampling point, with the proportions of Schistosoma haematobium and STH infections were imported into ArcGIS 9.3 to map areas at risk. Results: Out of 953 urine samples screened for schistosome eggs 253 (26.5%) were positive. All the communities were classified as moderate risk areas (prevalence < 50%) for schistosomiasis. Also, 79/143 (55.2%) soil samples screened were positive for STH eggs and larvae. The STH identified were Ascaris lumbricoides (49.0%), Hookworm species (16.8%), Strongyloides stercoralis (32.2%) and Trichuris trichiura (3.5%). All the communities were high risk areas (frequency > 50%) for contracting STH infections. Conclusion: Faecal contamination is a major factor aiding the continuous cycle of infection in this endemic zone; and may help to estimate the extent of the risk of schistosomiasis in STH endemic areas.