Genetic structure and geographical distribution of Bithynia siamensis sensu lato from Khong and Mounlapamok districts, Champasak Province, Laos

This study is the first to use DNA analysis to investigate Bithynia spp. in opisthorchiasis-endemic areas of Champasak Province, where B. s. goniomphalos lineages II and III were detected, but lineage I was not found. Our finding suggested that geographic or environmental factors influence the distribution of specific Bithynia lineages in this region. Many O. viverrini endemic areas in Southeast Asia still lack genetic data on Bithynia snails which could provide valuable insights into the transmission dynamics of opisthorchiasis. Therefore, further investigations should be conducted in these areas using cox1 and 16S rRNA sequences for comparison with previous studies.