STAPHYLOCOCCUS AUREUS FROM READY-TO-EAT FOOD AS A SOURCE OF MULTIPLE ANTIBIOTIC RESISTANCE GENES

Abstract

The emergence of antibiotic-resistant strains of S. aureus such as methicillin-resistant S. aureus (MRSA) is a worldwide problem. Ready-to-eat (RTE) food which does not need thermal processing before consumption could be a vehicle for the spread of antibiotic-resistant microorganisms. The present study evaluated the molecular genetic characteristics (RAPD) and pheno- and genotypical antimicrobial resistance profile of S. aureus isolated from 75 RTE food samples (sushi, hamburgers, salads). All of the isolates (n=32) were resistant to at least one class of antibiotic tested of which 75% strains were classified as multidrug resistant. Most of the isolates were resistant to cefoxitin (87,5%) followed by clindamycin (78,1%), tigecycline and quinupristin/dalfopristin (53,1%). All methicillin resistant staphylococci harbored mecA gene. Among tetracycline resistance isolates all of them harbored at least one gene: tet(M), tet(L) and/or tet(K) and 78,9% of them were positive for the Tn916/Tn1545-like integrase family gene. Our results indicated that retail RTE food could be considered an important route for transmission of antibiotic resistant staphylococci harboring multiple antibiotic resistance genes.