Development of a District-Level Model for the Prevention and Control of Opisthorchis viverrini Infection in a High-Prevalence Area

Abstract

This action research aimed to develop a district-level model for the prevention and control of opisthorchiasis in a high-prevalence area. It was conducted in Kud Rang District, Maha Sarakham Province, between February 2024 and April 2026. The target groups were residents aged 15 years and over, village health volunteers (VHVs), and network partners from the provincial to the community level. The instruments comprised a verbal risk-screening form, the OV-Rapid Diagnostic Test, a stage-of-change assessment form, and a LINE OA satisfaction questionnaire. Data were analysed using descriptive statistics, 95% confidence intervals, the chi-square test, and content analysis. The model achieved verbal risk-screening coverage of 72.6 and 73.9%, and opisthorchiasis infection screening coverage of 80.6 and 87.4% in 2024 and 2025, with treatment coverage of 98.2 and 100%, respectively. Behaviour modification by VHV health coaches enabled 65.0% of infected persons to abstain from raw fish for more than six months. Infection prevalence in 2024 and 2025 was 10.5 and 11.2%, the new infection rate was 11.9% (95% CI: 11.0-12.8), and the reinfection rate was 9.6% (95% CI: 7.5-12.3). The development yielded the C-LIVER Model, comprising collaboration building, leadership and capacity strengthening, identification and appropriate instruments, value-based service delivery, empowered community prevention, and real-time surveillance and review for empowerment; the model integrates screening, testing, treatment, behaviour modification, and community measures into a single system. Implementation should be continued for at least 3-5 years to assess the effectiveness and sustainability of the model, and a multi-site implementation study should be undertaken to test its applicability to other areas.