(Meticillin [originally spelled methicillin] resistant Staphylococcus aureus)
Derivatives of the common bacterium Staphylococcus aureus that are resistant to beta-lactam antibiotics including penicillin, meticillin, and cephalosporins. MRSA is endemic in hospitals in many countries around the world and is a common cause of nosocomial infection. MRSA often exhibits resistance to a wide range of antibiotic groups apart from beta-lactams. Over the last decade community-acquired MRSAs have emerged as a significant cause of infection in the community in many countries. There are several distinct major subgroups of MRSA and a wide variety of variants. In the healthcare setting, patients with open wounds, indwelling devices, or a weakened immune system are significantly more at risk of infection. Healthcare staff who do not follow good cross-infection control and prevention practice can spread MRSA from patient to patient. See also staphylococcus.
Dawson M. P., Smith A. J. Superbugs and the dentist: an update. Dent Update 2006;33(4):198–200, 202–4, 207–8.