Co-occurrence of mecA and Tetracycline Resistance Genes in Staphylococcus aureus in Nigeria: A One Health Systematic Review and Meta-Analysis with Empirical Validation

Abstract Background: Antimicrobial resistance (AMR) in Staphylococcus aureus, particularly methicillin-resistant S. aureus (MRSA), is a critical global health threat. In Nigeria, the co-occurrence of methicillin (mecA) and tetracycline (tet) resistance genes poses a severe clinical and One Health challenge, yet national estimates remain fragmented. Methods: We conducted a systematic review and meta-analysis following PRISMA guidelines . We searched PubMed, Scopus, Web of Science, and AJOL for studies reporting mecA and tet gene co-occurrence in Nigerian S. aureus isolates. Pooled prevalence was estimated using a random-effects model. To empirically validate meta-analytic trends, we conducted primary PCR-based molecular screening of contemporary local isolates.