Seroprevalence and associated risk factors of human fascioliasis in Yen Bai and Thanh Hoa provinces, Vietnam

Highlights
• Low seroprevalence of human fascioliasis in community-based survey in Vietnam.
• No Fasciola eggs were detected in stool.
• Ethnic minority and farmers had higher odds of fascioliasis seropositivity.
• Findings complement hospital-based data and guide One Health interventions.

Abstract
Fascioliasis is a zoonotic disease that affects human and animal health worldwide, especially in developing countries. Although fascioliasis is considered an emerging disease in Vietnam, community-based prevalence estimates are scarce. This study aimed to assess the prevalence and risk factors of fascioliasis in northern Vietnam. In 2018, a cross-sectional study was conducted involving 796 individuals from Yen Bai and Thanh Hoa provinces; stool and blood samples were collected from its members. Stool samples were analyzed for Fasciola eggs using the Kato-Katz and formalin-ether concentration techniques, while serum samples were analyzed for anti-Fasciola antibodies using ELISA. All participants aged 15 years and older completed a questionnaire on demographic characteristics and culinary practices. No Fasciola eggs were detected in stool samples (0 %, 95 %CI: 0.00–0.46); however, 2.6 % of participants were seropositive for fascioliasis (21/796, 95 %CI: 1.7 % – 4.0 %). Multivariable logistic regression showed a significantly higher risk of being seropositive among individuals of non-Kinh ethnicity (OR = 14.03, 95 % CI: 2.39–82.17), and among farmers (OR = 3.42, 95 % CI: 1.04–11.25). Lack of awareness about fascioliasis was associated with higher seropositivity (OR = 0.31, 95 %CI: 0.11–0.87). Our findings indicate that fascioliasis is mesoendemic in northern and north central Vietnam. Targeted educational campaigns should explain how transmission can be interrupted.