Staph 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.

Methicillin-resistant Staphylococcus aureus; Community-acquired MRSA (CA-MRSA); Hospital-acquired MRSA (HA-MRSA)
Definition MRSA infection is an infection with a strain of Staphylococcus aureus bacteria that is resistant to antibiotics known as beta-lactams. These antibiotics include methicillin, amoxicillin, and penicillin.

Causes Staphylococcus aureus (staph) are common bacteria that normally live on the skin. The bacteria also live harmlessly in the nasal passages of roughly 30% of the U.S. population. Staph can cause infection when they enter the skin through a cut or sore. Infection can also occur when the bacteria move inside of the body through a catheter or breathing tube. The infection can be minor and local (for example, a pimple), or more serious.

Most staph infections occur in people with weak immune systems, usually patients in hospitals and long-term care facilities. MRSA infections in hospitalized patients are known as healthcare-associated MRSA (HA-MRSA). People who have been hospitalized or had surgery within the past year are at high risk for HA-MRSA. People receiving certain treatments, such as dialysis, are also at high risk. MRSA bacteria account for a large percentage of hospital-acquired staph infections.

Over the past several years, MRSA infections in people not considered high-risk have increased. These infections, known as community-associated MRSA (CA-MRSA), occur in otherwise healthy people who have no history of hospitalization in the last year. Many such infections have occurred among athletes who share equipment or personal items (such as towels or razors) and children in daycare facilities.

Prevention Careful attention to personal hygiene is key to avoiding MRSA infections. Wash your hands frequently, especially if visiting someone in a hospital or long-term care facility. Do not share personal items such as towels or razors with another person -- MRSA can be transmitted through contaminated items. Cover all wounds with a clean bandage, and avoid contact with other people's soiled bandages. If you share sporting equipment, clean it first with antiseptic solution.

The Impact of Ultraviolet Light on MRSA