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Public Health - Seattle & King County

MRSA (Methicillin-resistant Staphylococcus aureus)

Staphylococcus aureus (also called 'staph') is a bacterium that is commonly found on human skin and inside the nose. It can colonize (live on) the skin without causing any illness or it can cause disease ranging from mild to serious. Some staph bacteria are resistant to certain antibiotics. Methicillin-resistant S. aureus bacteria (MRSA) are resistant to methicillin and related antibiotics. Other antibiotics can be used to treat a MRSA infection, but treatment may take longer. MRSA is spread by close contact with infected people or through items such as contaminated towels, soaps, sheets and clothes. About 85% of MRSA infections happen in healthcare settings (nosocomial infections) and the rest in the community. MRSA infections have been reported in dogs, cats, horses, cattle, sheep, rabbits, and chickens. Dogs, cats, horses and other animals can also be MRSA carriers without symptoms of infection. MRSA can be spread from humans to animals and from animals to humans.