Background: Opisthorchiasis, caused by Opisthorchis viverrini, is of considerable public health importance in Southeast Asia, particularly in Lao PDR and Thailand.
Objective: This study aims to analyze the risk areas for liver flukes in Surin province, Thailand using Geographic Information
Systems (GIS).
Material and Method: The 5 main factors (131 variables) were: (1) personal data (2) knowledge, attitude and practice, (3) health service unit, (4) environmental data, and (5) climate data. The relationship between these main factors and liver fluke
infection was analyzed using multiple regression analysis. Potential surface analysis (PSA) with geographic information
systems (GIS) was performed to create maps displaying areas at risk for liver fluke infection in Surin province.
Results: The population density (148-169 pop/km2; X73), human attitude (<50%; X111), and land use (wetland; X64), were statistically significant with liver fluke infection by a percentage of 88.60% (Adjusted R2 = 0.886). The heavy risk areas covered 221.39 km2 and including 8 districts; Si Narong, Sangkha, Phnom Dong Rak, Mueang Surin, Non Narai, Samrong Thap, Chumphon Buri and Rattanaburi.
Conclusion: Present study identifies the increased risk areas for liver flukes in Surin Province and may be useful for future
planning of prevention and control.

Keywords: Risk areas, Liver fluke, Surin province, Thailand, Geographic information system