Global Prevalence and Epidemiological Drivers of Fasciola Infection in Buffaloes: A Systematic Review and Meta-Analysis

Fasciolosis, caused by Fasciola hepatica and Fasciola gigantica, negatively impacts buffalo production systems worldwide as a parasitic and zoonotic disease. Due to their semi-aquatic foraging behavior, buffaloes (Bubalus bubalis) are highly exposed to Fasciola infections. The reported prevalence rates vary widely, hindering effective control strategies. This systematic review and meta-analysis estimated the global pooled prevalence of Fasciola infection in buffaloes and explored major sources of heterogeneity. Following PRISMA guidelines, major databases (PubMed/MEDLINE, Web of Science, ScienceDirect, CAB Abstracts, and Google Scholar) were searched from inception through September 2026. The primary synthesis used a random-effects binomial generalized linear mixed model (GLMM) with a logit link. Heterogeneity was quantified using Cochran’s Q, I2, and τ2; subgroup analyses and univariate meta-regression were used to explore study-level sources of variation, and Egger’s regression was used to assess funnel-plot asymmetry when at least 10 estimates were available. The final quantitative dataset comprised 64 publications contributing 73 effect estimates and 2,267,945 buffaloes after the removal of one exact duplicate estimate. The global pooled prevalence in buffaloes was 16.5% (95% CI: 12.1–22.0%), with very high heterogeneity (I2 = 99.8%; τ2 = 2.366 on the logit scale). The pooled prevalence was 45.7% in Europe, 19.5% in Asia, 4.2% in Africa, and 7.9% in the Americas. By parasite identification, the prevalence was 28.4% for F. gigantica, 16.6% for F. hepatica, and 13.0% for Fasciola spp.; by diagnostic method, it was 20.8% for fecal examination, 10.5% for post-mortem examination, and 11.7% for ELISA. Continent was a significant categorical moderator (Qm = 16.48, p < 0.001; R2 = 19.3%), whereas study period, diagnostic method, Fasciola identification, categorical sample size, and climatic zone were not. When the sample size was modeled continuously as ln(n), it was inversely associated with prevalence (Qm = 11.42, p < 0.001; R2 = 15.8%). Fasciola infections remain an important and highly heterogeneous problem in buffalo populations. The wide variation among settings, together with evidence of continent- and sample size-related effects, supports region-specific surveillance, standardized diagnostics, molecular species identification, and integrated One Health control rather than reliance on a single global prevalence estimate.