Methicillin-resistant Staphylococcus aureus and animals: zoonosis or humanosis?

Methicillin-resistant Staphylococcus aureus (MRSA) is increasing worldwide. Occasionally, animals are colonized or infected incidentally with human strains. Recently, however, new strains of MRSA emerging from within the animal kingdom, particularly in pigs, are causing human infection. MRSA has been reported in species as diverse as companion animals, horses and pigs, through to chinchillas, bats and parrots. In contrast, whereas strains of community-associated MRSA, the majority of which carry genes encoding Panton-Valentine leucocidin, are spreading rapidly in human populations, only sporadic cases have been reported in animals to date. Although MRSA has been found in some meat products, the implications for human infection through consumption are unclear. This review examines the epidemiology of MRSA in animals and human attendants/owners, the diagnosis and management of MRSA colonization, infection and infection control strategies in animals.