Abstract:Background: Schistosomiasis is a major health issue in developing countries. In the Philippines, S. japonicum primarily infects humans, with Oriental Mindoro heavily affected. Water flow direction influences the distribution of Oncomelania snails and parasite spread, shaping local transmission. Previous studies on environmental factors affecting snail survival are outdated or limited. This study examines how water flow affects snail and cercariae distribution in municipalities around Naujan Lake. Results aim to guide targeted efforts to reduce schistosomiasis. The study is recruitment complete and analysis done. Methods: This retrospective study analyzed GPS-mapped snail data from four Naujan Lake municipalities, testing samples for Schistosoma infection. Water current directions from government data were correlated with infection rates. ArcGIS visualized infected site distribution, and Chi-square tests in SPSS examined the link between water flow and parasite prevalence (P< 0.05). Results: Results revealed significant variation in snail abundance and infection rates associated with water flow patterns. In Socorro and Victoria, snails and infected cercariae were primarily found in midstream-to-upstream and downstream zones, respectively, with strong statistical correlations (P< 0.05). Pola exhibited minimal snail and cercariae presence, showing no significant link to water flow. Spatial mapping identified clusters of infected snails near river mouths and lake edges in southern and southwestern areas, particularly in Socorro and Victoria, designating these as high-risk transmission zones. Conclusion: The findings show that water flow direction significantly influences snail habitats and parasite spread in Oriental Mindoro. This knowledge supports targeted interventions to control snail populations and interrupt transmission. The study provides important evidence on hydrology and snail ecology that can enhance global schistosomiasis control by enabling more effective, site-specific strategies. These insights help address persistent hotspots, improve resource use, and reduce disease burden worldwide, aligning with WHO’s goals for elimination.
Keywords: Indigenous Health, Naujan Lake, Oncomelania snails, Schistosoma cercariae, water flow direction, spatial distribution
