The Global Seroprevalence of Equine Brucellosis: A Systematic Review and Meta-analysis Based on Publications From 1990 to 2022

Brucellosis, a bacterial infection caused by Brucella spp., is a widespread zoonosis concerning human and animal health. In equines, brucellosis may occur asymptomatically or with clinical signs such as arthritis, bursitis, and tenosynovitis. This study aims to ascertain the overall seroprevalence of equine brucellosis and its related factors, including geographic region, serological detection method, equine's species, gen-der, age, and body condition. This is because equine brucellosis is a zoonotic infection with significant epidemiological implications. The systematic literature search was conducted from January 1, 1990, to April 1, 2022, in the following electronic databases: Google Scholar, Scopus, Pub Med, Science Direct, Web of Science, Embase, Springer, and ProQuest. Based on the preferred reporting items for systematic reviews and meta-analyses (PRISMA) and inclusion criteria, 49 qualified studies were acquired from sev-eral countries. Because Egger's test result and the asymmetry in the funnel plot indicated significant pub-lication bias, the meta-analysis model was corrected using the trim-and-fill method. After correction, the pooled seroprevalence of equine brucellosis was 1.92% (95% CI, 0.67-3.79; estimated by the random effect model). Based on meta-regression analysis, the probable heterogeneity factors may be geographic areas (continents and countries). The brucellosis seroprevalence in equines was the lowest in Europe (0%, 95% CI, 0-0.1) and the highest in Asia (10.03%, 95% CI, 8-12.9). The highest overall estimate of seroprevalence of Brucella infection in equines based on a subset of serological tests was made using the serum agglu-tination test (10.2%, 95% CI, 7.7-13.4). The combined seroprevalence of brucellosis in donkeys (7.3%, 95% CI, 4.9-9.7) was higher than in other equine species. The overall seroprevalence of brucellosis in female equines was significantly higher than in males (OR = 1.437; 95% CI, 1.025-2.014); despite this, the overall seroprevalence had no significant difference based on other risk factors such as age and body condition. Understanding the epidemiology of this zoonotic infection in equines is critical for one-health integration. In addition, this study's results may be appropriate for controlling and managing equine brucellosis.(c) 2023 Elsevier Inc. All rights reserved.