MRSA (Methicillin-resistant Staphylococcus aureus)

What is MRSA?

MRSA (methicillin-resistant Staphylococcus aureus) is a type of bacteria that’s developed defense mechanisms (resistance) to antibiotics. MRSA infections are hard to treat because very few antibiotics are effective against them. MRSA most often causes skin infections but it can also cause serious infections in your lungs, heart and bloodstream.

MRSA used to spread mostly in healthcare settings — among people in hospitals or long-term care facilities (healthcare-acquired MRSA or HA-MRSA). But since the 1980s, cases of community-acquired MRSA (CA-MRSA), have been going up. CA-MRSA affects healthy people who haven’t been in a healthcare facility.

Types of MRSA infection

Types of MRSA infections include:

• Skin and soft tissue infections (SSTIs).
• Pneumonia.
• Bone and joint infections (osteomyelitis).
• Bacteremia (bacteria in your blood).
• Endocarditis (inflammation in your heart).

What’s the difference between a staph infection and MRSA?

Staph infections are any infections caused by the group of bacteria Staphylococcus aureus. MRSA is a specific type of staph infection that’s resistant to antibiotics. Staph infections, in general, are much more common and treatable than MRSA.

What are the symptoms of MRSA?

MRSA symptoms vary by where you’re infected. Some symptoms common to many types of MRSA infections include:

• Fever.
• Pain at infection site.
• A rash or area of skin that’s red, discolored, painful, swollen, or filled with pus or fluid. MRSA skin infections can sometimes be mistaken for spider bites.
• Cough.
• Shortness of breath.
• Chest pain.
• Fatigue.
• Muscle or joint pain.

What causes MRSA?

Strains of Staphylococcus aureus develop antibiotic resistance for many reasons. Sometimes, it happens naturally in the environment. Other times, it happens when the bacteria develop defense mechanisms to block or destroy antibiotic drugs. In hospitals and other healthcare settings, bacteria can become resistant to antibiotics that are used often.

Methicillin is a type of antibiotic related to penicillin. But despite MRSA’s name (methicillin-resistant Staphylococcus aureus), MRSA strains are usually resistant to many types of antibiotics, including:

• Other penicillin drugs, like amoxicillin and ampicillin.
• Cephalosporins, like cefepime.
• Carbapenems, like meropenem and imipenem.

HA-MRSA is usually resistant to more types of antibiotics than CA-MRSA.

How does MRSA spread?

Some people naturally carry MRSA on their skin or in their noses and never get sick from it (colonization). If you’re colonized with MRSA, you’ll test positive on nasal or skin swabs, even if you don’t have symptoms of an infection. You can still spread MRSA to others.

You can get MRSA through:

• Direct contact with someone who’s infected or colonized.
• Touching contaminated objects or surfaces. MRSA can sometimes survive on surfaces for weeks.
• Sharing contaminated items, such as bedsheets, clothes, medical or sports equipment, towels, shaving razors or utensils.
• Contaminated medical equipment and medical devices in your body (like a central venous line or breathing tube).

Is MRSA contagious?

Yes, MRSA is contagious. It can spread through skin-to-skin contact or on surfaces. Sometimes, people in the same family or living in the same household get it from each other.

What are the risk factors for MRSA?

You might be at a higher risk for a MRSA infection if you:

• Inject nonmedical drugs.
• Participate in contact sports.
• Work in a healthcare facility.
• Live in group conditions, such as military barracks or correctional facilities.
• Have certain illnesses that can weaken your immune system, like diabetes, kidney disease, HIV or cancer.
• Take immunosuppressive medications.
• Have a medical device that goes into your body.
• Have been in a hospital for a long time or live in a long-term care facility.

What are the complications of MRSA?

If providers can’t get rid of a MRSA infection with antibiotics, it can cause serious complications, including:

• Sepsis and septic shock (extreme reactions to an infection that lead to low blood pressure, tissue damage and organ failure).
• Respiratory failure.
• Loss of infected limbs (amputation).

How is MRSA diagnosed?

A healthcare provider diagnoses MRSA by sending a sample of body tissue or fluid to a lab to be tested. They might try to grow (culture) bacteria from the sample. Examples of samples they could test include:

• Blood.
• Tissue from a wound.
• Urine (pee).
• Sputum (mucus coughed up from your lungs).

Providers sometimes test for MRSA colonization with a skin or nasal swab.

How is MRSA treated?

Providers treat MRSA infections by caring for open wounds and finding antibiotics that are effective against the strain of MRSA you have. Wound treatment includes draining fluid and surgically removing infected tissue. They also might remove infected medical devices, including prosthetics. Providers treat severe MRSA infections with intravenous (through your vein) antibiotics in the hospital.

Antibiotics for MRSA infections

Antibiotics a provider might use to treat MRSA include:

• Vancomycin.
• Rifampin.
• Trimethoprim/sulfamethoxazole (TMP/SMX).
• Ceftaroline.
• Linezolid.
• Daptomycin.
• Clindamycin.
• Doxycycline.
• Delafloxacin.

Sometimes, MRSA is called a “superbug” because its defense mechanisms against so many antibiotics make it hard to treat. One strategy providers might use is to treat you with more than one type of antibiotic at a time.

Can MRSA be prevented?

Healthcare providers follow safety and sterilization rules to prevent healthcare-acquired infections like MRSA. These include:

• Washing their hands.
• Disinfecting surfaces.
• Sterilizing medical devices.
• Screening patients and visitors to healthcare facilities.
• Quarantining (isolating) people with MRSA infections so it doesn’t spread to other people.

Some steps you can take to prevent CA-MRSA include:

• Keep wounds clean and bandaged.
• Don’t share personal items like towels and razors.
• Don’t reuse needles used for injecting nonmedical drugs or medications (even your own).
• Place a towel on a locker room bench before sitting on it naked.
• Regularly wash sheets, towels and workout clothes in the recommended water temperature. Dry everything in a dryer. You don’t need to use bleach or wash potentially contaminated items separately.
• Shower immediately after working out or participating in activities that increase your risk of MRSA exposure.
• Use disinfectants that kill germs to wipe down high-touch areas like light switches, remote controls and athletic equipment. Check labels to find disinfectants that kill staph bacteria.
• Wash your hands frequently with hot water and soap for at least 20 seconds. Use alcohol-based hand sanitizer when hand-washing isn’t possible.

Ask your provider how long you need to use invasive medical devices like catheters and how to prevent infection while you need the device.

What can I expect if I have MRSA?

If you have a skin infection, your provider will surgically treat and drain your wounds. They might give you topical or oral antibiotics. You’ll need to be treated in the hospital if you have a severe or invasive MRSA infection.

CA-MRSA, especially skin infections, can be easier to treat than HA-MRSA. But up to 70% of MRSA skin infections come back (recur) after successful treatment. This might be because other people you live with or are around a lot are colonized with MRSA, or because MRSA lives on objects and surfaces for a long time, where it can reinfect you.

Will I need to be isolated if I have MRSA?

If you’re being treated in a hospital, you might be in a room by yourself or with special restrictions to prevent spreading MRSA. Your providers may ask any visitors to take precautions, like wearing medical gloves, gowns or masks.

How long is MRSA contagious?

MRSA is contagious as long as tests can detect the bacteria on or in your body. Your provider will swab your nose or skin to test for MRSA to determine if you’re still contagious.

Can MRSA be cured?

Yes, more than half of all MRSA cases are cured with antibiotics, and providers successfully treat most MRSA skin infections. But serious infections — like pneumonia, endocarditis and bacteremia — can quickly get worse before a provider can find a treatment that works.

What’s the mortality rate of MRSA?

The mortality (death) rate of MRSA depends on where you’re infected. For MRSA bacteremia — one of the more serious forms — the mortality rate is between 20% and 50%.

When should I see a healthcare provider?

If you have an implanted medical device or a weakened immune system, ask your healthcare provider what signs of infection you should look out for. Follow up with them if you have any concerning symptoms. Always see a provider if you have a large wound or one that’s not healing.

Even when you’re in the hospital, communication with your healthcare team is important. Let them know if you’re experiencing symptoms of an infection, like pain, rapid heart rate, weakness or fever.

When should I go to the ER?

Go to the emergency room if you have any signs of severe illness, including:

• Fever over 103 degrees Fahrenheit or 40 degrees Celsius.
• A wound that’s painful, foul-smelling, or filled with green, yellow or brown liquid.
• Chest pain.
• Difficulty breathing.
• Sudden drop in blood pressure (symptoms include weakness, dizziness and fainting).

What questions should I ask my doctor?

It might be helpful to ask your healthcare provider:

• What are my treatment options?
• When can I go back to work/school?
• How do I keep from spreading MRSA to others?
• What can I do to prevent an infection like this in the future?

A note from Cleveland Clinic

You might hear about MRSA in scary-sounding headlines. But healthcare providers work hard to prevent its spread in hospitals and other facilities, and cases of HA-MRSA have declined in both the U.S. and Europe. Still, all types of MRSA can cause potentially fatal infections.

If you have symptoms of a serious infection or a wound that’s not healing, especially if you have an implanted medical device or weakened immune system, get immediate medical attention. Tell your providers about any medical conditions or devices you have, or if you’ve spent a lot of time in hospitals recently. This information can help them get to the bottom of your symptoms more quickly and treat any infections as soon as possible.