National Reference Laboratory for Staphylococci, University of Patras, Patras, Greece;2. Department of Microbiology, School of Medicine, University of Patras, Patras, Greece;3. Department of Hygiene and Technology of Foods of Animal Origin, School of Veterinary Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece;4. Department of Public Health, School of Medicine, University of Patras, Patras, Greece;5. Department of Microbiology, School of Medicine, University of Thessaly, Larissa, Greece