Methicillin-Resistant Staphylococcus aureus (MRSA)
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Once S. aureus is tested in the lab and known to be resistant to certain antibiotics, we call it methicillin-resistant Staphylococcus aureus. MRSA is pronounced either “M-R-S-A” or “mer-sa”. It is resistant to certain antibiotics called beta-lactams. Roughly 2% of the population has MRSA on their skin or in their nose. Most of the time it does not cause any sickness or infection.
Staph can easily be spread through touch. When a person touches the infected area and does not clean their hands afterwards and then touches another person or an object, the germs are spread by their hands.
Staphylococcus aureus is a type of bacteria that about 30% of the population has in their nose or on their skin. Most of the time is does not cause any sickness or infection. When this germ does cause a problem, a doctor may choose to treat it with antibiotics. Sometimes the antibiotics do not work and we call the staph resistant or methicillin-resistant staphylococcus aureus. This type of staph is commonly called MRSA and pronounced either “M-R-S-A” or “mer-sa”. It is resistant to certain antibiotics called beta-lactams. Roughly 2% of the population has MRSA on their skin or in their nose (Gorwitz RJ et al. Journal of Infectious Diseases. 2008:197:1226-34).
Both types of staph can be spread through touch. When a person touches the infected area and does not clean their hands after and then another person or an object, the germs are spread by their hands. Sometimes people do not know they have MRSA and do not clean objects after touching or using them, so the germs stay on the object when the next person uses it.
Having contact with someone else’s MRSA skin infection or personal items they have used, like towels or razors that touched their infected skin can also spread the germs. These types of infections are most likely to be spread in places where people are in close contact with others—for example, schools and locker rooms where athletes might share razors or towels.
As with all staph infections, recognizing the signs and receiving treatment for staph skin infections in the early stages reduces the chances of the infection becoming severe.
MRSA in healthcare settings usually causes more severe and potentially life-threatening infections, such as bloodstream infections, surgical site infections, or pneumonia. The signs and symptoms will vary by the type and stage of the infection.
In the community, most MRSA infections are skin infections that may appear as pustules or boils which often are red, swollen, painful, or have pus or other drainage. They often first look like pimples, spider bites or bumps that are red, swollen, and painful. These skin infections commonly occur at sites of visible skin trauma, such as cuts and scrapes, and areas of the body covered by hair (e.g., back of neck, groin, buttock, armpit, beard area of men).
MRSA can be spread by not cleaning our hands once we have contaminated them.
Factors that have been associated with the spread of MRSA skin infections include: close skin-to-skin contact, openings in the skin such as cuts or abrasions, contaminated items and surfaces, crowded living conditions, and poor hygiene. People may be more at risk when these factors are present in certain locations, including: athletic facilities, dormitories, military barracks, households, correctional facilities, and daycare centers.
MRSA is not naturally found in the environment (e.g., soil, the ocean, lakes). MRSA contaminates objects and surfaces outside the body if someone touches infected skin or certain areas of the body where these bacteria can live (like the nose) and then touches the object or surface. Keeping skin infections covered with bandages is the best way to reduce the chance that surfaces will be contaminated with MRSA.
Even if surfaces have MRSA on them, this does not mean that you will definitely get an infection if you touch these surfaces. MRSA is most likely to cause problems when you have a cut or scrape that is not covered. That’s why it’s important to cover your cuts and open wounds with bandages. MRSA can also get into small openings in the skin, like the openings at hair follicles.
The best defense against MRSA is good hygiene.
- Keep your hands clean
- Use a barrier like clothing or towels between you and any surfaces you share with others, like gym equipment
- Shower immediately after activities that involve direct skin contact with others
- Clean, disinfect and cover any cuts or wounds you may get
- If you or someone you know has an MRSA infection frequently disinfect commonly touched, hard surfaces
- Always tell your healthcare provider, like a doctor or nurse, that you have had MRSA.
Children do not need to be excluded from child care, school or extra-curricular activities. Draining, open wounds, or abrasions should be cleaned and covered with a dressing until healed.
Texas has limited MRSA information that is reportable through TxHSN.
- 2012: Of the 609 S. aureus isolates, 335 isolates (55%) tested susceptible to oxacillin/methicillin
- 2013: Of the 790 S. aureus isolates, 352 (44.55%) tested susceptible to oxacillin/methicillin
- 2014: Of the 710 S. aureus isolates, 315 (44.33%) tested susceptible to oxacillin/methicillin