Global prevalence and epidemiological dynamics of bovine ephemeral fever: a misclassification-adjusted bayesian meta-analysis.

Abstract

BACKGROUND: Bovine ephemeral fever (BEF) is an economically important yet under-characterized arboviral disease of cattle and water buffalo, with substantial impacts on productivity and herd health across tropical and subtropical regions. Despite decades of surveillance, global prevalence estimates remain uncertain due to pronounced diagnostic heterogeneity and uneven geographic coverage. METHODS: We conducted a systematic review and Bayesian hierarchical meta-analysis of BEF serological and molecular prevalence data. Fifty-two studies published between 1967 and 2025 from 19 countries were included in the systematic review, of which laboratory-confirmed data from 16 countries contributed to quantitative meta-analysis and Bayesian modelling, representing 335,754 bovines. Observed prevalence estimates were corrected for imperfect diagnostic sensitivity and specificity using a misclassification-adjusted Bayesian framework, which improves accuracy by accounting for false positives and false negatives and harmonizing prevalence estimates across diagnostic methods, including differences between serological assays that measure cumulative exposure and molecular assays that detect short-lived active infection, and spatiotemporal models were applied to reconstruct national trends. RESULTS: After correcting for diagnostic misclassification, the global true seroprevalence of BEF was estimated at 0.33. The corresponding misclassification-adjusted prevalence of active infection was 0.241; however, hierarchical modelling of outbreak-concentrated PCR and virus-isolation data produced a higher posterior mean of 0.56, reflecting the clustering of molecular sampling during epidemic periods. Marked geographic heterogeneity was observed, with posterior seroprevalence approaching 0.84 in Pakistan and Turkey, compared with substantially lower inferred immunity in Israel and Australia. Spatiotemporal analyses revealed declining long-term exposure in China and Australia, whereas recurrent outbreak-driven transmission persisted in parts of the Middle East and South Asia. Shifts in diagnostic practices over time, together with ongoing viral lineage diversification, further contributed to regional variation in reported prevalence. CONCLUSIONS: This study provides the first global, misclassification-adjusted synthesis of BEF epidemiology. The findings highlight the importance of standardized diagnostic protocols, enhanced genomic surveillance, and regionally targeted control strategies, as well as providing a solid quantitative baseline for future epidemiological assessment and policy development aimed at reducing the global burden of BEF.