ORIGINAL RESEARCH A survey of the occurrence and properties of methicillin- resistant Staphylococcus aureus and methicillin-resistant Staphylococcus intermedius in water buffalo milk and dairy products in Turkey SEBNEM PAMUK, 1 YELIZ YILDIRIM, 2 * ESRA SEKER, 3 ZEKI GURLER 1 andRECEP KARA 1 1 Food Hygiene and Technology Department, Faculty of Veterinary Medicine, Afyon Kocatepe University, 03200, Afyonkarahisar, Turkey, 2 Food Hygiene and Technology Department, Faculty of Veterinary Medicine, Erciyes University, 38039, Kayseri, Turkey, and 3 Microbiology Department, Faculty of Veterinary Medicine, Afyon Kocatepe University, 03200, Afyonkarahisar, Turkey *Author for correspondence. E-mail: yyildirim@erciyes.edu.tr Ó 2012 Society of Dairy Technology Antimicrobial resistance, b-lactamase activity and mecA gene of Staphylococcus aureus and Staphylo- coccus intermedius isolated from raw water buffalo milk and dairy products in Turkey were determined. All strains showed resistance to at least one antibiotic but none was resistant to vancomycin. Of the 97 S. aureus and 35 S. intermedius strains, 9 (9.2%) and 2 (5.7%) were resistant to oxacillin and harboured mecA gene. b-lactamase activity of 13.4% and 5.7% of S. aureus and S. intermedius strains was positive, respectively. Overall, 2.5% and 0.55% of the samples were contaminated with methicillin-resistant S. aureus and S. intermedius, respectively. Keywords Antibiotic resistance, Coagulase-positive staphylococci, Methicillin-resistant Staphylococcus aureus, Methicillin-resistant Staphylococcus intermedius, Water buffalo milk. INTRODUCTION Recently, the increasing prevalence of methicillin- resistant Staphylococcus aureus (MRSA) strains has become an additional infection control problem in human and veterinary medicine (Kwon et al. 2005; O’Mahony et al. 2005; Wylie and Nowicki 2005). Methicillin-resistant S. aureus is predomi- nantly a human pathogen, and molecular typing has revealed that certain clones have spread widely both between humans and animals (Hunter et al. 2010). European Antibiotic Resistance Surveil- lance System (EARSS, 2009) data have shown that the incidence of bacteraemia caused by MRSA in hospitals in Europe has increased in many coun- tries between 2001 and 2006. Methicillin-resistant S. aureus is known to be capable of causing wide range of hospital-acquired MRSA infections (Herold et al. 1998). In addition, community-acquired MRSA has now become a major concern (Otter and French 2008). The resis- tant bacteria can be transferred to humans through the consumption, handling and spilling of unpasteurised milk and milk products (Manie et al. 1999). The spreading of MRSA or other multiresis- tant S. aureus by food or food handlers is a subject of concern and should be prevented in the food chain (Andre ´ et al. 2008). In addition to the role of S. aureus in the aetiol- ogy of staphylococcal food poisoning (SFP), a causative role may be assumed particularly for canine Staphylococcus intermedius isolates via canine human contact. Therefore, S. intermedius should not be disregarded when screening food products for contamination with enterotoxin-pro- ducing pathogens or studying outbreaks of SFP (Becker et al. 2001). Ecology and epidemiology of S. intermedius are not clearly defined and it is rarely isolated in humans except from the infec- tions resulting from animal bites and occasionally from raw and processed food (Khambaty et al. 1994). But it was reported that S. intermedius hav- ing an enterotoxin production ability was held responsible for food-borne intoxication case that affected 265 people in California and Nevada in 1991 (Hirooka et al. 1988). Vol 65 International Journal of Dairy Technology 1 doi: 10.1111/j.1471-0307.2012.00832.x