Studies excluded from the review.

BackgroundOpisthorchis viverrini (OV) is a major public health concern in the Lower Mekong Basin. This study aimed to synthesize all field-based empirical research examining risk factors and control strategies for OV in the Lower Mekong Basin (LMB).MethodsWe performed a systematic review of published literature (1990–2024) on field-based OV studies that examined risk factors and control strategies in LMB. The literature search included two databases: PubMed and Scopus. We included field-based studies that analysed or reported on OV risk factors or control strategies using quantitative or mixed methods and were written in English. We excluded secondary research articles, laboratory-based research, qualitative only research and studies conducted outside LMB. All prospective studies underwent quality assessment using the Newcastle-Ottawa Scale or the Cochrane Risk of Bias tool II prior to final inclusion.ResultsWe identified 807 citations from PubMed and Scopus. From those, 56 studies were included in the review and three additional studies were identified from citation searches of included studies in the review. Studies were extracted and analysed by research focus. Among the included studies, 45 were conducted in Thailand, 11 in Laos, two in Vietnam, and one in Cambodia. Factors associated with OV infection were explored in 51 studies, and 11 studies reported on control strategies. General education was found to be an important protective factor for OV infection. Consumption of raw or undercooked fish was the most reported risk factor. Anthelmintic treatment was the primary control strategy across studies.ConclusionThis review summarises risk factors and control strategies reported in LMB since 1990. We found that sociodemographic, environmental, and economic factors were important predictors of OV infection. Given the multitude of risk factors for infection identified in this study and the complex lifecycle of OV, we recommend a One Health approach, that recognises the interconnectedness of human, animal and environmental health, for future health promotion and control strategies.Trial registrationPROSPERO registration ID: CRD42022357080.