Schistosomiasis, caused by Schistosoma trematodes transmitted by intermediate host snails, remains a waterborne disease of concern in Côte d’Ivoire. Despite mass drug administration, a high prevalence of intestinal schistosomiasis persists in the western part of the country.

This study was carried out to better understand the transmission ecology of schistosomes and other trematodes in this area by identifying the open freshwater sources most at risk.

Cross-sectional malacological studies were carried out from August to October 2022 in Biankouma, Ouaninou and Touba districts. Environmental and water parameters were recorded. Snails were collected and intermediate hosts Biomphalaria pfeifferi and Bulinus globosus spp. were tested for cercarial emission. Principal component analysis was used to assess the relationship between environmental parameters of sampling sites and snail species.

1,014 snails from seven species were collected from 23 water sites classified into four categories: rivers, streams, ponds and rice fields. The rivers and streams had more snail species than rice fields and ponds. Among the snails collected, 71.5% were Bi. pfeifferi and 28.5% were Bu. globosus. The cercariae found were echinostomes, strigeids, Xiphidiocercariea and schistosomes. The presence of Bi. pfeifferi’s was positively associated with pH and negatively with high temperature and conductivity. Bu. globosus was negatively associated with the total values of total dissolved solids.