Malacological Study of Snail from some Fresh Water Bodies in Kano State, Nigeria

A malacological survey was conducted to assess the molluscan fauna, occurrence, and distribution of freshwater snail species in selected water bodies within Kano State, Nigeria. Three dams, Watari, Guzu-Guzu, and Tiga, located across three local government areas, were selected, comprising a total of 21 sampling sites. Seven freshwater snail species were identified, with Bulinus globosus exhibiting the highest occurrence (193 individuals; 44.3%), followed by Lymnaea natalensis (77; 19.5%), Pirenella conica (15.5%), Biomphalaria pfeifferi (69; 12.4%), Bulinus rohlfsi (20; 5.1%), Bellamya bengalensis (18; 4.6%), and Pila globosa showing the lowest occurrence (10; 2.6%). Chi-square analysis revealed significant differences in species distribution across the dams (χ² = 148.6, df = 12, p < 0.001). Watari and Tiga dams harbored the largest snail populations, while Pirenella conica was the most widely distributed species, present at all sampling sites. Cercarial shedding rates varied significantly among snail species and locations, with Fisher’s exact test indicating significant associations between snail species and Schistosoma cercarial infection prevalence (p = 0.002). Although Tiga Dam recorded the highest abundance of snail hosts for Schistosoma haematobium, cercarial shedding was relatively low, likely due to the presence of immature cercariae during sampling. These findings suggest that increases in snail populations may elevate the risk of human schistosomiasis through greater exposure to cercariae during water contact activities. Further longitudinal studies are recommended to elucidate seasonal infection dynamics and the spatial distribution of snail intermediate hosts in the region.