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Definition of Methicillin-resistant staphylococcus aureus

Methicillin-resistant staphylococcus aureus: Staphylococcus aureus (a type of staph bacteria) resistant to the antibiotic methicillin. Abbreviated MRSA.

MRSA first cropped up among persons in hospitals and other health facilities, especially among the elderly, the very sick, and those with an open wound (such as a bedsore) or a tube going into their body (such as a urinary catheter or IV catheter).

MRSA has since been found to cause illness in the community outside of hospitals and other health facilities. MRSA in the community is associated with recent antibiotic use, sharing contaminated items, having active skin diseases, and living in crowded settings.

Picture of MRSA (methicillin-resistant Staphylococcus aureus) Infection

Skin infections caused by MRSA have clustered among injecting drug-users, Native Americans, prison inmates, and athletes in close-contact sports. Community-associated MRSA infections typically cause skin lesions (such as boils), but also can cause severe illness. Some children have died from community-associated MRSA.

The transmission of MRSA is largely from people with active MRSA skin infections. MRSA is almost always spread by direct physical contact, and not through the air. Spread may also occur through indirect contact by touching objects (such as towels, sheets, wound dressings, clothes, workout areas, sports equipment) contaminated by the infected skin of a person with MRSA. Just as S. aureus can be carried on the skin or in the nose without causing any disease, MRSA can be carried in this way also. This is known as colonization.

MRSA infections are usually mild superficial infections of the skin that can be treated successfully with proper skin care and antibiotics. MRSA, however, can be difficult to treat and can progress to life-threatening blood or bone infections because there are fewer effective antibiotics available for treatment.

If someone has an MRSA infection, they can help from spreading it by keeping infections, particularly those that continue to produce pus or to drain material, covered with clean, dry bandages; by advising close contacts to wash their hands frequently with soap and warm water, especially if they change the bandages or touch the infected wound or potentially infectious materials; by not sharing personal items (such as towels, washcloth, razor, clothing) that may have had contact with the infected wound; by washing linens and clothes with hot water and laundry detergent and drying them in a hot dryer; and by telling healthcare providers that you have an antibiotic-resistant staph skin infection.