The imporTance of meThicillin-resisTanT StaphylococcuS aureuS in human medicine

Staphylococcus aureus (S. aureus) is one of the most important bacterial opportunistic pathogens in humans. It easily adapts to the various environmental conditions. Very important is rapid development of resistance to different antimicrobial agents. Especially important is the resistance to beta-lactam antibiotics (so called methicillin-resistant S. aureus: MRSA). MRSA strains differ according to the setting they cause infections to healthcare-acquired strains, community-acquired strains and animal strains. Healthcare-acquired MRSA strains were responsible for the largest epidemic of healthcare-associated infections that ever occurred in the world; community-acquired MRSA strains are huge problem in USA, not so important in Europe. Animal MRSA strains are new addition to human pathogens, but they are not very frequent. In Croatia, MRSA strains are big problem in hospitals but with the tendency of decreasing in recent years; community-acquired MRSA strains are so far very rare, and infections caused by animal MRSA strains are still not described in humans, although they are present in pig farms.