Superbug Staph (MRSA) Spread in Community

Commonly called the "superbug," MRSA, or methicillin-resistant Staphylococcus aureus, is a bacterium that can cause serious infections. It is "super" because it is resistant to numerous antibiotics, including methicillin and penicillin, so it is harder to treat than many bacterial infections.

MRSA belongs to the large group of bacteria known as staphylococci, often referred to as staph. Up to 33% of all people carry the staph bacteria within the lining tissues of the nose, but it normally does not cause an infection. In contrast, only about 2% of the population are carriers of MRSA.

Infections with MRSA can occur in hospitals and other institutional health-care settings, such as nursing homes, where they tend to strike older people, those who are very ill, and people with a weakened immune system. In health-care settings, MRSA is a frequent cause of surgical wound infections, urinary tract infections, bloodstream infections (sepsis), and pneumonia.

MRSA outbreaks, however, can also occur in people who have not been hospitalized or had a medical procedure performed in the past year and who do not have immune deficiency. These infections are termed community-associated MRSA infections (CA-MRSA). CA-MRSA infections have increased dramatically in the U.S. since the mid-1990s.

Community-associated MRSA infections usually affect the skin, causing pimples and boils in otherwise healthy people. Infected areas may be red, swollen, painful, and have pus or other drainage.

MRSA is typically transmitted from people with active MRSA infections. MRSA and other staph infections are primarily transmitted by the hands, which may become contaminated by contact with colonized or infected people or items or surfaces contaminated with body fluids containing MRSA. Skin-to-skin contact, cuts or abrasions of the skin, contaminated items and surfaces, crowded living conditions, and poor hygiene have all been associated with the transmission of MRSA in the community.

If you believe you have a staph infection, visit your health-care professional. Most staph and MRSA infections can be treated with antibiotics, but skin lesions may also be treated by drainage of the lesion under sterile conditions. MRSA infections that have been treated can recur and require further treatment.

Good hygiene is the most effective way to prevent MRSA infections and to prevent the recurrence of treated lesions. Hands should be kept clean by frequent washings or use of hand-sanitizer lotions. Openings in the skin, such as cuts, should be kept clean and covered until healed. Contact with other people's skin wounds should be avoided, and personal-care items such as towels and razors should not be shared with others.