MRSA infection

Methicillin-resistant Staphylococcus aureus (MRSA) infection is caused by a strain of staph bacteria that's become resistant to the antibiotics commonly used to treat ordinary staph infections.

Most MRSA infections occur in people who've been in hospitals or other health care settings, such as nursing homes and dialysis centers. When it occurs in these settings, it's known as health care-associated MRSA (HA-MRSA). HA-MRSA infections typically are associated with invasive procedures or devices, such as surgeries, intravenous tubing or artificial joints.

Another type of MRSA infection has occurred in the wider community — among healthy people. This form, community-associated MRSA (CA-MRSA), often begins as a painful skin boil. It's spread by skin-to-skin contact. At-risk populations include groups such as high school wrestlers, child care workers and people who live in crowded conditions.

Symptoms Causes Risk factors Complications Prevention

Staph skin infections, including MRSA, generally start as small red bumps that resemble pimples, boils or spider bites. These can quickly turn into deep, painful abscesses that require surgical draining. Sometimes the bacteria remain confined to the skin. But they can also burrow deep into the body, causing potentially life-threatening infections in bones, joints, surgical wounds, the bloodstream, heart valves and lungs.

When to see a doctor

Keep an eye on minor skin problems — pimples, insect bites, cuts and scrapes — especially in children. If wounds become infected, see your doctor. Do not attempt to treat an MRSA infection yourself. You could worsen it or spread it to others.

© 1998-2015 Mayo Foundation for Medical Education and Research (MFMER). All rights reserved. Terms of use