DETECTION OF MEC(A) GENE IN CEFOXITIN AND OXACILLIN (METHICILLIN) RESISTANT STAPHYLOCOCCUS AUREUS ISOLATED FROM READY-TO-EAT FOODS IN JOS, PLATEAU STATE, NIGERIA

Abstract

Staphylococcus aureus is a significant foodborne pathogen that can cause serious infections in humans, and its resistance to commonly used antibiotics poses a major public health threat. This study determined the prevalence of the mecA gene in methicillin-resistant S. aureus isolated from ready-to-eat foods sold in Jos, Nigeria. A total of 120 food samples were evaluated for bacterial load, Antibiotic susceptibility using the disc diffusion method and detection of methicillin resistance through PCR amplification of the mecA gene. The results indicate substantial bacterial contamination of the foods, with TBC ranging from 1.60 × 10⁶ to 1.04 × 10⁷ CFU/g and TSC ranging from 1.57 × 10⁵ to 6.15 × 10⁵ CFU/g. Among the food types, ‘suya’ showed the highest mean TBC (1.04 × 10⁷ CFU/g) and jollof rice the lowest (1.60 × 10⁶ CFU/g). The overall detection rate of S. aureus was 30.83%, with the highest occurrence in jollof rice (50.00%). Antibiotic susceptibility profiles revealed high resistance to oxacillin (81.9%) and cefoxitin (70.3%), confirming the circulation of MRSA in the food chain. Gentamicin (78.4%) and vancomycin (73.0%) were the most effective antibiotics, while notable resistance was found against trimethoprim (64.9%). Of 37 isolates, 26 (70.30%) were mecA carriers, with a 21.67% prevalence in the RTE foods. The Jollof rice exhibited the highest mecA occurrence (80.00%), while other popular dishes showed 50% to 70% positivity. The polymerase chain reaction amplification revealed a distinct band of the mecA genes at 533 base pairs on the agarose gel, providing strong evidence for the presence of methicillin-resistant S. aureus (MRSA) in the tested food samples. This study underscores the need for monitoring and control measures regarding MRSA in food products to protect public health.