MRSA is a bacterial infection that is highly resistant to antibiotics, which may lead to its popularity as a tag. MRSA stands for methicillin-resistant Staphylococcus aureus. Staphylococcus aureus is the bacteria responsible.
Because MRSA is resistant to antibiotics, it is sometimes referred to as a "superbug." Although MRSA is antibiotic-resistant, it can usually be treated with vancomycin. Recently, however, some strains of MRSA have developed some resistance to vancomycin, making it even more difficult to treat.
Most MRSA infections arise in hospitals or other health care facilities, but "community-associated" infections have been on the rise and are responsible for serious skin and soft-tissue infections and a serious form of pneumonia.