1. MRSA Slideshow Pictures
2. Take the MRSA Quiz!
3. Staph Infection Slideshow Pictures

Medical Author:

Charles Patrick Davis, MD, PhD

Charles Patrick Davis, MD, PhD

Dr. Charles "Pat" Davis, MD, PhD, is a board certified Emergency Medicine doctor who currently practices as a consultant and staff member for hospitals. He has a PhD in Microbiology (UT at Austin), and the MD (Univ. Texas Medical Branch, Galveston). He is a Clinical Professor (retired) in the Division of Emergency Medicine, UT Health Science Center at San Antonio, and has been the Chief of Emergency Medicine at UT Medical Branch and at UTHSCSA with over 250 publications.

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Medical Editor:

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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In this Article

• MRSA infections facts
• What is methicillin-resistant Staphylococcus aureus (MRSA)?
• What does a MRSA infection look like?
• What are the signs and symptoms of MRSA infection?
• How is MRSA infection transmitted or spread?
• How is MRSA diagnosed?
• How can people prevent MRSA infection?
• How should caregivers treat MRSA patients at home?
• What is the prognosis (outlook), and what are the potential complications for people with MRSA infections?
• What is the treatment for MRSA infection?
• What is a "superbug"?
• Where are other MRSA information sources?
• Pictures of MRSA - Slideshow
• Take the MRSA Quiz!
• Pictures of Staph Infection - Slideshow
• MRSA Infection FAQs
• Patient Comments: MRSA - Describe Your Experience
• Patient Comments: MRSA -Treatment
• Find a local Infectious Disease Specialist in your town
• MRSA Infection Index

MRSA stands for methicillin-resistant Staphylococcus aureus (S. aureus) bacteria. This organism is known for causing skin infections in addition to many other types of infections. There are other designations in the scientific literature for these bacteria according to where the bacteria are acquired by patients, such as community-acquired MRSA (also termed CA-MRSA or CMRSA), hospital-acquired or health-care-acquired MRSA (also termed HA-MRSA or HMRSA), or epidemic MRSA (EMRSA). Statistical data suggest that as many as 19,000 people per year have died from MRSA in the U.S.; data supplied by the CDC in 2010 suggest this number has declined by about 28% from 2005 to 2008, in part, because of prevention practices at hospitals and home care.

Although S. aureus has been causing infections (Staph infections) probably as long as the human race has existed, MRSA has a relatively short history. MRSA was first noted in 1961, about two years after the antibiotic methicillin was initially used to treat S. aureus and other infectious bacteria. The resistance to methicillin was due to a penicillin-binding protein coded for by a mobile genetic element termed the methicillin-resistant gene (mecA). In recent years, the gene has continued to evolve so that many MRSA strains are currently resistant to several different antibiotics such as penicillin, oxacillin, and amoxicillin (Amoxil, Dispermox, Trimox). HA-MRSA are often also resistant to tetracycline (Sumycin), erythromycin (E-Mycin, Eryc, Ery-Tab, PCE, Pediazole, Ilosone), and clindamycin (Cleocin). In 2009, research showed that many antibiotic-resistant genes and toxins are bundled and transferred together to other bacteria, which speed the development of toxic and resistant strains of MRSA. S. aureus is sometimes termed a "superbug" because of its ability to be resistant to several antibiotics.

What does a MRSA infection look like?

In addition, these organisms have been termed "flesh-eating bacteria" because of their occasional rapid spread and destruction of human skin. Additionally, a number of older (2004-2008) web and popular press articles are titled or include the erroneous term "MRSA virus." This is a misnomer that has confused many people; there is no contagious MRSA virus, and if readers examine these articles, they may realize the content is usually about MRSA bacteria.

Unfortunately, MRSA strains of bacteria can be found worldwide. In general, healthy people with no cuts, abrasions, or breaks on their skin are at low risk for getting infected. However, the bacteria can be passed from person to person by direct contact with infected skin, mucus, or droplets spread by coughs in both adults and children. Indirect contact also can spread the bacteria; for example, touching items like towels, utensils, clothing, or other objects that have been in contact with an infected person can spread the bacteria to other uninfected individuals. Investigators estimate that about one out of every 100 people in the U.S. are colonized with MRSA (have the organisms in or on their body but not causing infection), and these individuals may transmit MRSA bacteria to others by the same methods listed above. Another term for people colonized with MRSA is "carrier" which means the person carries the organism in or on the body and may transfer the organism to another person who subsequently may become infected. A common place for carriers to harbor MRSA organisms is the nose.