Methicillin Resistant Staphylococcus aureus (MRSA)

Methicillin is an antibiotic that is commonly used to treat Staphylococcus aureus, a common type of bacteria that is often found in the nose, but can also grow in wounds and other sites of the body. Over time, the many strains of S. aureus have become resistant to methicillin. The drug is no longer effective. The primary way individuals get MRSA is by contact (direct or indirect) with a person who either has a wound infection, an infection of the respiratory tract, or who is colonized with the bacteria especially in the hospital (HA MRSA). MRSA are frequent causes of healthcare-associated bloodstream and catheter-related infections. MRSA now composes over 50% of S. aureus infections in U.S. hospitals and varying percentages in different countries. It has also an emerging cause of community-associated (CA MRSA), especially skin and soft tissue infections and necrotizing pneumonia.