What causes methicillin-resistant Staphylococcus aureus (MRSA)?

Dr. Mehmet Oz, MD
Cardiology (Cardiovascular Disease)

Staphylococcus aureus is a germ usually found in our nasal passages that can cause an infection in the right circumstances. When that happens, antibiotics can keep it in check. But methicillin-resistant Staphylococcus aureus (MRSA) is a particularly tough strain of Staph that isn't vulnerable to antibiotics. MRSA first raised trouble in hospital settings, but in the past decade, hospitals have begun to win the war against this fatal super bug while the rest of us are losing it. In some parts of the country, as many as 10% of people harbor MRSA. Although you can still contract MRSA in a health-care setting, these days you're more likely to get it from a neighbor or a friend.

When MRSA meets an open sore on your body, it moves in and multiplies at an alarming rate, causing you to develop a fever and your wound to become red, swollen, painful, and oozing. If you have a wound that won't heal, there's a good chance it has MRSA.

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Up to one-third of the population carries some type of the bacteria Staphylococcus aureus constantly in their skin or nose. If they are not experiencing any symptoms from the bacteria, these people are called carriers. When the bacteria come in contact with an open cut, wound, or scrape, infection can form.

Methicillin-resistant Staphylococcus aureus (MRSA) carriers are people who carry a specific kind of the Staphylococcus aureus bacteria in their bodies. MRSA bacteria are particularly resistant to antibiotics. Hospital workers are often MRSA carriers, since they're frequently around antibiotics and so MRSA bacteria is the only Staphylococcus aureus strain that can survive in their environment. Consequently, many people who develop MRSA get it in hospitals from hospital personnel who are carrying the bacteria.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.