As part of the Staphylococcaceae Genus Staphylococcus aureus is a Gram positive coccus, facultatively anaerobic. This bacteria is potentially pathogenic and may cause a wide range of infections and intoxications. These bacteria are found on skin and nasal swabs.
This rapidly evolving bacterial species has been a primary target in the realm of antibiotic research and development. Penicillin was effective against S. aureus when it was first introduced, but within only 6 years up to 25% of hospital-acquired strains were found to be penicillin resistant. The development of vancomycin and methicillin (and derivatives) offered new hope, but by the late 1980s, so-called MRSA (methicillin-resistant S. aureus) was a major threat in hospital-acquired infections. The incidence of community-acquired MRSA likewise has risen in the last few years. Fortunately, vancomycin has remained effective against MRSA, though resistant strains have been reported.