S. aureus is not always pathogenic, but it is a common cause of skin infections including abscesses, respiratory infections such as sinusitis, and food poisoning.
The emergence of antibiotic-resistant strains of S. aureus such as methicillin-resistant S. aureus(MRSA) is a worldwide problem in clinical medicine.
An estimated 20% to 30% of the human population are long-term carriers of S. aureus which can be found as part of the normal skin flora, in the nostrils, and as a normal inhabitant of the lower reproductive tract of women.
