Methicillin-resistant Staphylococcus aureus (MRSA) is a type of bacteria that is resistant to certain antibiotics. These antibiotics include methicillin and other more common antibiotics such as amoxicillin, oxacillin and penicillin.

Staph infections, including MRSA, occur most frequently among persons in hospitals and health care facilities (such as nursing homes and dialysis centers) who have weakened immune systems.

As the epidemiology of MRSA disease changes, including both community and health care associated disease, accurate information on the scope and magnitude of the burden of MRSA disease in the US and Canadian population is needed to set priorities for prevention and control. In the hospital, MRSA infections are associated with greater lengths of stay, higher mortality, and increased costs.

In US hospitalized patients, MRSA has been a problem since the 1960s (approximately 20% of bloodstream infections in the US hospital setting have been caused by S aureus). The proportion of hospital onset S aureus infections that were methicillin-resistant reached 64.4% in US intensive care units in 2003. The first national survey to determine the prevalence of antibiotic-resistant organisms in Canada has found that on any given day, about one in 12 adults in hospitals across Canada are either colonized or infected with a superbug.

Although more recently there has been increased surveillance activity for invasive MRSA infections in the community, surveillance for MRSA bloodstream infections in the United States traditionally has been limited to hospital onset (i.e., nosocomial) disease.

RELATED INFO:

• Methicillin-resistant Staphylococcus aureus (MRSA)
• Invasive Methicillin-Resistant Staphylococcus aureus Infections in the United States
• MRSA Skin Infection Signs and Symptoms