Distribution and Ecological Habitat Characteristics of Biomphalaria straminea — Shenzhen City, Guangdong Province, China, August–December 2023

What is already known about this topic?Biomphalaria straminea (B.straminea) is an invasive snail and a key intermediate host of Schistosoma mansoni (S. mansoni), which was previously widespread in Shenzhen's major rivers.What is added by this report?In contrast to historical records, no live snails were detected in rivers or reservoirs, whereas stable populations persisted in agricultural areas.Infested habitats show eutrophication and higher levels of Ca 2+ , HCO 3 -, and PO 4 3-.All the samples tested negative for S. mansoni.What are the implications for public health practice?B. straminea shows apparent redistribution into agricultural environments, increasing spatial overlap with human activities and raising a theoretical transmission risk of S. mansoni.Surveillance and control efforts should prioritize agricultural ecosystems over urban waterways.