Abstract

This study aimed to investigate the prevalence, antibiotic resistance, and genetic relationships of Staphylococcus aureus isolated from frozen and minced meat products in Alexandria, Egypt. A total of 200 samples (100 frozen meat and 100 minced frozen meat) were collected from local supermarkets at Alexandria City, Egypt. Conventional methods beside VITEK 2 system were used for identification, while antibiotic susceptibility testing was performed to detect Methicillin-resistant Staphylococcus aureus (MRSA) and Vancomycin-resistant Staphylococcus aureus (VRSA). Enterobacterial Repetitive Intergenic Consensus (ERIC)-PCR was employed to analyze Genetic diversity. Lastly, gene sequencing was conducted for antibiotic resistance genes (mecA, vanA, and vanB). Results showed that 7% of frozen meat and 8% of minced meat samples were positive for coagulase positive Staphylococcus aureus using conventional methods and VITEK confirmation system. Among Staphylococcus aureus isolates, 57.1% from frozen meat and 50% from minced meat were MRSA, with one VRSA isolate from each category at incidence rate 14.3 and 12.5%, respectively. ERIC-PCR revealed high genetic similarity (>95%) among some isolates, suggesting a common source of contamination. Sequencing confirmed high similarity (97.42%) of the mecA gene with known MRSA strains. These findings highlight the need for improved food safety measures to prevent the spread of antibiotic-resistant S. aureus in the food supply chain.

Key words: Staphylococcus.aureus, Frozen, minced meat, MRSA, VRSA, antibiotic resistance genes, ERIC-PCR