Carbapenem-resistant Enterobacteriaceae from dairy cattle milk: A systematic review and meta-analysis

Carbapenem-resistant Enterobacteriaceae (CRE) have been detected in dairy cattle milk, raising concerns about public health risks. This study aimed to assess the global prevalence of CRE in dairy cattle milk through a systematic review and meta-analysis, following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Retrieved articles from four databases were initially screened based on predefined inclusion criteria. The meta-analysis included 49 studies (2011-2024), covering 28,134 milk samples and 3462 Enterobacteriaceae isolates globally. Data from the full text were extracted to a Microsoft Excel spreadsheet and analysed using the 'meta' R package in R v.4.3.0 software for pooled prevalence and subgroup meta-analysis with a random-effects for logit transformation. Heterogeneity was assessed using Cochran's Q statistic (χ²), p-value and I² statistic. Publication bias and sensitivity were evaluated using Egger's test, funnel plot, trim and fill plot, and leave-one-out test. Globally, the prevalence of CRE in dairy cattle milk was 0.73 % (95 % CI, 0.37-1.41). Subgroup meta-analysis based on continent, sample type, Enterobacteriaceae species, diagnostic method, antibiotic type, and interpretation guideline revealed no significant differences among the criteria within the subgroup. Although the overall pooled prevalence of CRE in dairy cattle milk is relatively low, it raises public health concern regarding raw milk consumption. This emphasizes the need for regular monitoring with in a One Health framework for CRE in the dairy industry to anticipate potential transmission between humans, animals, and the environment.