SPREAD OF METHICILLIN-RESISTANT STAPHYLOCOCCUS AUREUS (MRSA) IN DAIRY COWS IN ASSOCIATION WITH PIG FARMING

Among bacteria Staphylococcus aureus plays a very relevant role both in humans and animals infections. It is present primary on the skin and through direct contact it can be transmitted to new hosts and can also be spread wherever in the environment. As a consequence, S. aureus reservoir are living carriers and contaminated inanimate objects too (e.g. needle sharing among drug users, used disposable materials in health care facilities, foreign bodies in skin wounds and even dust in contaminated environments). S. aureus causes a variety of infections generating abscesses in many body districts, in general it is the most frequent responsible for skin and soft tissue infections (SSTIs). Pneumonia, fasciitis, cellulitis, empiema of natural cavities (e.g. gallbladder), osteomyelitis, arthritis, implanted-device associated infections are only some of the most common diseases caused by S. aureus. Extremely severe and life-threatening are endocarditis and blood stream infections up to septicemia. S. aureus can be acquired everywhere but is a typical heath care-associated infection. Analogies can be found with S. aureus infections regarding animals, especially companion animals whose hospitalization is becoming more and more similar to that reserved to humans. It is present in a wide range of animal species, including dogs, cats, rabbits, horses, cattle, pigs, poultry, and exotic species, both as a cause of infection and in healthy carriers. Identification of MRSA in various species and in food has led to concerns about the roles of animals, both pets and livestock, in the epidemiology of MRSA infection and colonization in humans. A special issue regards dairy production animals, in particular cows, for which S. aureus is the most important udder pathogen. The present work means to investigate the presence, importance and origin of S. aureus affecting dairy cows belonging to strains defined methicillin-resistant (MRSA). Since pigs has been found the first food-producing animal species carrying MRSA and recognized as a reservoir, the likely relationships with dairy herds present on the same area will be discussed.