Methicillin-resistant Staphylococcus aureus

What is MRSA?

MRSA stands for methicillin-resistant Staphylococcus aureus. MRSA is a type of Staphylococcus bacterium that has developed resistance to the antibiotic ampicillin and other penicillins. Staphylococci bacteria are "carried" by healthy people in a variety of body sites (on the skin and in the nasal passage) without disease being present. Most people do not get sick from staphylococcal bacteria, even MRSA.

How do individuals get MRSA?

Individuals get MRSA the same way they get other strains of S. aureus that are sensitive to methicillin. The chief 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.

Does everyone who is exposed to MRSA become infected?

No. Some individuals who are exposed to MRSA become "colonized" which means that the bacteria are present, growing and multiply without observable signs of disease. MRSA colonization occurs on the skin surface, in the nasal passage, in the sputum or in the urine. Other individuals who are exposed to MRSA never become colonized. MRSA colonization may precede or lead to infection in persons with weakened immune systems. However, persons who get MRSA infections are usually already very ill from other medical conditions.

How are MRSA infections treated?

Effective antibiotics to treat MRSA infection include bactrim, vancomycin and teichoplanin. Only patients with symptomatic MRSA infection should be treated; MRSA colonization should usually not be treated.

How long will MRSA last?

The length of illness caused by MRSA infection depends upon the severity of the infection, the response to antibiotic therapy, and the individual's overall health. After infection has been resolved, the individual may remain intermittently or persistently colonized with MRSA and may or may not develop future infection(s).

What precautions should be followed when I go home?

Hand washing is the most important measure. Always wash hands carefully after using the toilet, using household hand soap for at least 15 seconds. If you require continued care at home, you, or whomever is caring for you, should wear gloves when handling body fluids (urine, wound drainage, etc.), when providing care, or contacting surfaces contaminated with body fluids. Disposable items soiled by body fluids (dressings, diapers, used gloves, etc) should be placed in the trash. Good cleaning with a household disinfectant such as bleach is adequate. Laundry can be done in accordance with manufacturer's directions using standard detergent (add bleach for items heavily soiled with body fluids). Dishes and utensils can be washed as usual.

Each year, Medical College of Wisconsin physicians care for more than 180,000 patients, representing nearly 500,000 patient visits. Medical College physicians practice at Children's Hospital of Wisconsin, Froedtert Memorial Lutheran Hospital, the Milwaukee VA Medical Center, and many other hospitals and clinics in Milwaukee and southeastern Wisconsin.