Staphylococcus aureus is a bacterium that is a common coloniser of human skin and mucosa. Staphylococcus aureus can cause disease, particularly if there is an opportunity for the bacteria to enter the body.
Image courtesy of K Hiramatsu
Illnesses such as skin and wound infections, urinary tract infections, pneumonia and bacteraemia (blood stream infection) may then develop if the bacteria enter the body. Staphylococcus aureus can also cause food poisoning. Most strains of this bacterium are sensitive to many antibiotics, and infections can be effectively treated. Some S. aureus bacteria are resistant to the antibiotic meticillin, termed meticillin-resistant Staphylococcus aureus (MRSA).