Global prevalence of Mycobacterium avium subsp. paratuberculosis in sheep: Systematic review and meta-analysis

This report presents a systematic review and meta-analysis on the global prevalence of paratuberculosis in sheep, focusing on seropositivity of Mycobacterium avium subspecies paratuberculosis (MAP). This investigation included 1676 records initially, identified from the databases Web of Science, Scopus, Medline and Science Direct. After filtering and reading, twenty-eight articles were selected for the final analysis. The results showed that the pooled prevalence of animals positive for MAP was 8.02 % (95 % CI = 5.04–12.52 %) with significant heterogeneity (I² = 99.3 %), which suggests that there was high variability among results. The prevalence varied according to the continent, such that it was highest in South America (24.45 %) and lowest in Africa (1.34 %). In addition, meta-analysis per herd indicated that the global prevalence was 55.51 % (95 % CI = 44.96–65.58 %), with heterogeneity that was also high (I² = 96.8 %). Analysis of Doi plots demonstrated that there was slight positive asymmetry (LFK index 1.28), which suggests the possibility of publication bias. The meta-analysis demonstrated variation in global prevalence rates of MAP in sheep, with high dissemination among herds, especially in South America and Asia. The heterogeneity of the data indicates methodological differences among studies, thus highlighting the need for standardized investigations to better understand the epidemiology and control of paratuberculosis in sheep globally.