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Methicillin-resistant Staphylococcus aureus (MRSA)

Methicillin-resistant Staphylococcus aureus (MRSA) is a type of bacteria that can cause infection in people. "Regular" strains of staph bacteria can usually be treated by the antibiotic Methicillin. However, some strains of staph have developed that resist the effect of Methicillin and similar drugs. These bacteria are called MRSA. MRSA is hard to treat because it resists so many antibiotics.