Is MRSA Contagious?

  • Medical Author:
    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.

  • Medical Editor: Melissa Conrad Stöppler, MD
    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.

View the Staph Infection Slideshow

What is MRSA?

MRSA is the short form of methicillin-resistant Staphylococcus aureus and refers to strains of gram-positive coccal-shaped (round) bacteria that are resistant to several antibiotics. MRSA causes mainly skin infections in nonhospitalized people; in hospitalized patients, it can cause sepsis, surgical site infections, and pneumonia. All of these infections may be difficult to treat because of MRSA's resistance to antibiotics.

Is MRSA contagious?

MRSA is very contagious under certain circumstances (when skin alterations or damage are present); spread occurs through person-to-person contact with a skin infection or even indirect contact, such as contact with a MRSA-infected person's clothing or towels or even from benches in gyms. All MRSA needs to establish itself is a small break in the skin or mucosa. This is important because no breaks means no infection; for example, MRSA skin-infected or MRSA-colonized pregnant females seldom infect their fetus or infants. However, many activities such as kissing, saliva exchange, and sexual contact, although somewhat less likely to transfer MRSA to another, can cause infection if the skin or mucosa is damaged. Hospitalized patients, if they have MRSA pneumonia, may transfer the organisms to others through the air by contaminated droplets. Bodies of people who die from MRSA infections often have viable MRSA on their surfaces, and these organisms can infect other people. The incubation period for MRSA ranges from one to 10 days.

What is the incubation period for MRSA?

For most staph infections, including MRSA, the incubation period is often indefinite if the organisms are colonizing (not infecting) an individual (see above). However, the incubation period for MRSA often ranges from one to 10 days if it enters broken skin or damaged mucous membranes.

Quick GuideMRSA Infection: Causes, Symptoms, and Treatment

MRSA Infection: Causes, Symptoms, and Treatment

MRSA Symptoms and Signs

Most MRSA infections are skin infections that produce the following signs and symptoms:

  • Cellulitis (infection of the skin or the fat and tissues that lie immediately beneath the skin, usually starting as small red bumps in the skin with some areas resembling a bruise)
  • Boils (pus-filled infections of hair follicles)...

What is the contagious period for MRSA?

As long as there are viable MRSA bacteria in or on an individual who is colonized with these bacteria or infected with the organisms, MRSA is contagious. Consequently, a person colonized with MRSA (one who has the organism normally present in or on the body) may be contagious for an indefinite period of time. In addition, MRSA organisms can remain viable on some surfaces for about two to six months if they are not washed or sterilized.

How will I know I have MRSA?

Most MRSA skin infections first appear as a reddish bump that quickly becomes swollen, painful, and warm and contains or drains pus; they can occur almost anywhere on the body. The infected person may also develop a fever. Hospitalized patients may show surgical wound infections, pneumonia, or sepsis. However, the definitive way to diagnose MRSA is to have a doctor culture the MRSA bacteria (skin lesion, biopsy, or nasal swab) and then show the organisms are resistant to several different antibiotics.

How is MRSA transmitted?

MRSA in the community is spread from person to person by direct contact; in addition, indirect contact is also a means of spread because the bacteria can survive on objects like towels, benches, shaving equipment, and other objects. For a person to become infected, MRSA usually needs to have a breach (abrasion, cut, rash, or puncture) in the skin. Hospital spread of MRSA can include the above methods in addition to spread by blood, saliva, and/or droplets in the air that can land on people's skin or other surface if the person has pneumonia. Hospitalized patients who are MRSA carriers or infected with MRSA usually are put under isolation conditions (for example, gloves, masks, gowns, and minimized physical contact by visitors) to help prevent MRSA spread.

People who are colonized with MRSA far less likely to transmit the organisms to others; transmission is more likely if the patient is infected with MRSA.

How will I know I am cured of MRSA?

Many people are cured of MRSA when the symptoms resolve. However, a few individuals (about two of 100 people) carry MRSA as either transient organisms or colonizing organisms in some body areas such as the nasal mucosa but show no signs of infection. Occasionally, people can be cured of their carrier situation by topical antibiotics when they no longer are positive for MRSA cultures. Prevention of MRSA infections may be accomplished by good hand washing and body cleaning hygiene practices, especially after playing contact sports or if people live in crowded areas (dorms, camps, or barracks, for example). Although cleaning clothing and other items helps reduce the chance of getting MRSA, using a disinfecting agent like bleach, when feasible, offers an even better chance of prevention.

When should I contact a medical caregiver about MRSA?

If you know you have had person-to-person contact with someone diagnosed with MRSA and you begin to develop any symptoms, contact a physician urgently. If you develop symptoms or signs that might be due to MRSA, contact a medical caregiver to help diagnose your condition with tests for MRSA. If you are being treated for an infection with antibiotics and the infection is not better or is getting worse and/or you are developing fevers, you should urgently or emergently, depending on the severity of symptoms, see a physician.

REFERENCES:

United States. Centers for Disease Control and Prevention. "Methicillin-resistant Staphylococcus aureus (MRSA) Infections." Aug. 4, 2015. <http://www.cdc.gov/mrsa/>.

Wisconsin Department of Health Services. "MRSA methicillin-resistant Staphylococcus aureus -- Frequently Asked Questions." Aug. 4, 2016. <https://www.dhs.wisconsin.gov/disease/faq-mrsa.htm>.

Quick GuideMRSA Infection: Causes, Symptoms, and Treatment

MRSA Infection: Causes, Symptoms, and Treatment

Subscribe to MedicineNet's Skin Care & Conditions Newsletter

By clicking Submit, I agree to the MedicineNet's Terms & Conditions & Privacy Policy and understand that I may opt out of MedicineNet's subscriptions at any time.

Reviewed on 9/23/2016
References
REFERENCES:

United States. Centers for Disease Control and Prevention. "Methicillin-resistant Staphylococcus aureus (MRSA) Infections." Aug. 4, 2015. <http://www.cdc.gov/mrsa/>.

Wisconsin Department of Health Services. "MRSA methicillin-resistant Staphylococcus aureus -- Frequently Asked Questions." Aug. 4, 2016. <https://www.dhs.wisconsin.gov/disease/faq-mrsa.htm>.

Health Solutions From Our Sponsors