Molecular Typing and Phenotypic and Genotypic Evaluation of Antibiotic Resistance and Virulence Factors of the Methicillin-Resistant Staphylococcus Aureus Bacteria Isolated From Vegetable and Salad Samples

Abstract

BackgroundMethicillin-resistant Staphylococcus aureus is an important cause of foodborne diseases. The present research evaluated the antibiotic resistance properties, distribution of virulence factors, and molecular typing of MRSA bacteria isolated from vegetable and salad samples. MethodsThree-hundred and fifty vegetable and salad samples were examined for the presence of S. aureus using the culture. MRSA bacteria were identified using cefoxitin and oxacillin disk diffusion. The phenotypic pattern of antibiotic resistance was assessed by disk diffusion. ResultsThe PCR evaluated the distribution of antibiotic resistance and virulence genes. Forty-five out of 350 (12.85%) vegetable and salad samples were positive for S. aureus. Twenty-six isolates out of 45 (57.77%) S. aureus bacteria were determined as MRSA. MRSA bacteria harbored the uppermost prevalence of resistance against cefoxitin (100%), ceftaroline (100%), penicillin (100%), tetracycline (88.46%), gentamicin (80.76%), trimethoprim-sulfamethoxazole (69.23%), and erythromycin (69.23%). The prevalence of MRSA bacteria resistance recovered from vegetable and salad samples against more than seven antibiotic agents was 12.50% and 27.77%, respectively. BlaCTX-M (100%), blaZ (100%), aacA-D (61.53%), tetK (57.69%), dfrA1 (46.15%), and vanA (42.30%) were the most commonly detected antibiotic resistance genes. PVL (57.69%), coa (53.84%), and hla (38.46%) were the most commonly detected virulence factors amongst the MRSA bacteria. ConclusionMRSA isolates had a similarity lower than 80%, categorized in the same group. The presence of one or more virulence factors and antibiotic resistance genes amongst the resistant-MRSA bacteria signifies an important threat rendering the consumption of contaminated vegetables and salads.