Seroprevalence of African Horse Sickness in East Africa: A Systematic Review and Meta-analysis

African Horse Sickness (AHS) is a highly infectious, vector-borne viral disease of equids that causes substantial morbidity, mortality, and economic losses in endemic regions of Africa. East Africa is considered an important endemic area for AHS; however, available evidence on the seroprevalence of the disease remains fragmented and heterogeneous across countries, equid species, diagnostic methods, and time periods. Individual serological studies report widely varying prevalence estimates, making it difficult to assess the true burden of AHS and to inform evidence-based surveillance and control strategies. The purpose of this study is to systematically identify, appraise, and synthesize published and unpublished serological studies reporting African Horse Sickness seroprevalence among equids in East Africa. A comprehensive literature search will be conducted across multiple international and regional databases, including PubMed, Scopus, Web of Science, ScienceDirect, Google Scholar, and African Journals Online. Eligible studies will be screened, and data will be extracted using predefined criteria and standardized forms. Where sufficient data are available, a quantitative synthesis will be performed using random-effects meta-analysis to estimate pooled seroprevalence and corresponding 95% confidence intervals. Statistical heterogeneity will be assessed using the I² statistic, and subgroup and meta-regression analyses will be conducted to explore potential sources of heterogeneity, including country, equid species (horses, donkeys, and mules), diagnostic test type, and study period. The methodological quality of included studies will be assessed using a validated risk-of-bias tool for prevalence studies. The expected outcomes of this research include robust pooled estimates of AHS seroprevalence in East Africa, identification of spatial and methodological patterns influencing reported prevalence, and a critical appraisal of the existing evidence base. The findings are expected to support animal health authorities, researchers, and policy makers by providing a clearer understanding of AHS epidemiology in the region and highlighting gaps for future surveillance, research, and control efforts.