Staphylococcus aureus is a type of bacteria that is commonly found on the skin and in the nose of healthy individuals. While it usually does not cause any harm, it can cause infections if it enters the body through a cut or other opening. Methicillin-resistant Staphylococcus aureus (MRSA) is resistant to several common antibiotics, including methicillin, penicillin and amoxicillin. This means that these antibiotics are not effective in treating MRSA infections.
Digitally coloured micrograph by National Institute of Allergy and Infectious Diseases (NIAID).
