Zobayda Farzana Haque, Abdullah Al Momen Sabuj, Md. Muket Mahmud, Amrita Pondit, Md. Ariful Islam and Sukumar Saha
This study was designed to isolate and characterize the Staphylococcus aureus from raw cow’s milk and some other dairy products sold in the local markets of Mymensingh district of Bangladesh by using conventional methods and molecular techniques. Raw cow’s milk, pasteurized milk, yogurt, roshmalai, cheese, lassi, matha, milk-shake, custard, faluda, pudding and borhani sampled from different retail shops and renowned restaurants of the local markets of Mymensingh. Out of 72 samples tested, all the samples revealed presence of Staphylococcus spp. and 57 isolates found coagulase positive S. aureus. The antimicrobial susceptibility pattern of the 57 pathogenic isolates was determined by using 10 commercially available antimicrobial drugs by disk diffusion assay. It exposed that majority of the isolates (79.16%) showed resistant to more than three antimicrobial agents. Among 57 isolates, 14 (24.56%) showed resistance against both methicillin and oxacillin, also intermediately resistant against vancomycin. Molecular detection of mecA and mecC gene in the 14 methicillin and oxacillin resistant isolates for the identification of methicillin resistant Staphylococcus aureus (MRSA) strains revealed 8 isolates (57%) from raw milk, yogurt, roshmalai, borhani and cheese to be positive for mecA gene while it was not detected in any other of the samples. None of the tested samples found mecC positive. Our findings revealed that the milk and dairy food products sold at local markets of Mymensingh are contaminated with multidrug resistant S. aureus elucidating a possible risk of MRSA infection which is alarming for both human and animal health.