Résumé
Objectives: Urinary schistosomiasis is known to be endemic in the lake Nokoué areas of the District of So-Ava. For the past ten years, the National Control Programme for Communicable Diseases of the Ministry of Health has been making efforts
to control schistosomiaisis morbidity through mass drug treatment with Praziquantel. This study aimed to assess the diversity and dynamic of potential snails known as schistosomiasis intermediate hosts. Methodology and Results: This study was carried
out for 12 months (from July 2015 to June 2016) and consisted in the periodical analysis of the physical and chemical water parameters (temperature, oxygen concentration, pH, nitrite and nitrate rates. Salinity, total dissolved solids (TDS) and,
biochemical oxygen demand) in relation with diversity, distribution and relative abundance of freshwater snails (Bulinus forskalii, B. globosus and B. truncatus). To this end, seven harvesting sites on Lake Nokoué were, reasonably selected for
monthly hydrobiological and malacological data monitoring. The results showed a variable correlation between the dynamic of schistosomiasis intermediate host snailsm and several physico-chemical water parameters. Bulinus globosus was negatively
influenced by salinity and nitrate rates while B. forskalii was negatively influenced by pH, Oxygen, TDS, salinity and nitrate rates. The three species of freshwater snails were strongly influenced by the water temperature. Conclusion: The results
suggest a seasonal schistosome transmission induced by the seasonal dynamic of intermediate host snails. Water quality seems appropriate to the development of host snails from December to March and would be the strong period of schistosomiasis
transmission. However, furthermore studies will need for well understanding the dynamic transmission necessary for developing adapted strategy control.