Identification of Biomphalaria sp. and other freshwater snails in the large-scale water transposition project in the Northeast of Brazil

The wide eco-bio-social intervention generated by the SaoFrancisco River Integration Project (PISF) may contribute to the dispersion or introduction of schistosomiasis intermediate hosts in areas without prior recording. The objective was to characterize the limnic malacofauna and its distribution along watersheds involved in the PISF. A cross-sectional study based on the collection of mollusks from 33 water bodies, from Aurora, Brejo Santo, Jaguaretama, Jaguaribara, Jati e Mauriti municipalities in the Ceara (CE) State was developed. The conchological characteristics were used to identify snails at the genus level. The snails of the genus Biomphalaria were analyzed for the presence of Schistosoma mansoni cercariae and the molecular identification (only mollusks from Brejo Santo-CE) for differentiation between species. The following species were found: Biomphalaria sp.; Drepanotrema sp.; Melanoides sp.; Physa sp.; and Pomacea sp. Pomacea sp. (75.8%) and Biomphalaria sp. (72.7%) were the most prevalent species. All municipalities showed Biomphalaria sp. Biomphalaria straminea (Porcos Stream) and Biomphalaria kuhniana was identified in the Boi 1 and Cipo reservoirs (Brejo Santo). The evaluated municipalities under the influence of the PISF present areas with potential for schistosomiasis transmission. It is necessary to intensify control actions and health surveillance in these areas.