Metycylinooporny Staphylococcus aureus [MRSA] - wystepowanie u zwierzat a potencjalne zagrozenia zdrowia czlowieka

Due to the widespread prevalence of methicillin-resistant Staphylococcus aureus (MRSA) it has been included in the group of microorganisms causing severe human and animal infections. These bacteria occur in cattle, sheep, pigs, horses, dogs, cats, rabbits and poultry. The main diseases that are caused by S. aureus are dermatosis, mastitis, arthritis and urinary tract infections. People may develop more serious complications; e.g. pneumonia, endocarditis, bacteraemia. Moreover, these microorganisms are frequently connected with postoperative wound infections. The first MRSA strains emerged in the early 1960s after the acquisition of the methicillin resistance gene mecA, which is carried by the staphylococcal chromosomal cassette mec (SCCmec). The mecA gene encodes for a penicillin-binding protein (PBP2a) which has a low affinity to β-lactam antibiotics. Epidemiological data suggests that MRSA isolates from various animal species are genetically very similar or even indistinguishable from human isolates. The transfer of MRSA strains can occur between animals and humans as well as vice versa. The antibiotics that are effective for the treatment of infections caused by MRSA are still glycopeptides: vancomycin and teicoplanin, mupirocin and linezolid. However, there are already strains resistant to all known antibiotic groups. MRSA may be a source of antibiotic resistance genes and contribute to the spread of drug-resistance genetic elements to other disease-causing microorganisms.