Methicillin-resistant Staphylococcus aureus (MRSA) has become a hot topic both in the healthcare arena and at the dinner table. News reports have alerted the general public about this infection and its potentially dire implications. MRSA infections are linked to high costs and poor outcomes. Fear of exposure to MRSA and other infections has even led some people to cancel or postpone elective surgery.

What is MRSA? Where did it come from?

MRSA is a specific strain of the S. aureus bacterium, a common pathogen normally present in the body flora and commonly found on the skin and in the mucous membranes of healthy people. In the 1940s, most S. aureus organisms were sensitive to the then newly available penicillin. But by the 1950s, more than half of S. aureus cultures showed penicillin resistance.

In 1960, methicillin (a semisynthetic penicillin) was developed to treat penicillin-resistant infections. But S. aureus evolved again, becoming resistant to methicillin and many other first-line antibiotics. This resistant strain was easily transmitted and hospital patients began to experience S. aureus infections they didn’t have at admission.

Two basic types of MRSA exist. One is healthcare associated (HA-MRSA); the other, community acquired (CA-MRSA). Though the two differ distinctly, some experts worry the distinction will blur as more CA-MRSA makes its way into healthcare settings and more HA-MRSA follows healthcare workers home—possibly leading to infections that are much harder to manage and eradicate.

How does MRSA spread?

About one-third of the general population carry staphylococcal microbes. Estimates of healthcare workers’ carrier status range from 50% to 90%. The most common carriage site is the anterior nares. MRSA is highly resilient and can live without a host for an indeterminate time.

The pathogen is transmitted in one of three ways:

• patient to healthcare worker
• patient to patient (with a healthcare worker as the vector)
• healthcare worker to patient.

The resulting infection can be devastating, lengthening hospital stays, increasing associated costs, and causing death. According to a 2009 report by the Centers for Disease Control and Prevention (CDC), more than 90,000 life-threatening illnesses and nearly 19,000 deaths associated with MRSA occur yearly in the United States. The CDC found nearly 85% of MRSA cases were linked to healthcare settings. (See Preventing MRSA outside the healthcare setting by clicking on the pdf icon above.)

Preventing MRSA outside the healthcare setting

By taking the following actions, you can help prevent the spread of methicillin-resistant Staphylococcus aureus (MRSA):

• Practice strict hand washing before going to the cafeteria or other nonpatient areas of the hospital and before leaving the clinical area to go home.
• Change the clothes you wore during clinical practice before you go out into the community.
• As soon as you get home from work, take a hot shower using plenty of soap. Then immediately launder and disinfect the clothes you wore on duty, washing them separately from other clothes.
• Teach patients about the proper use of antibiotics to discourage them from requesting antibiotics for every illness.
• Promote infection-control practices among consumers and patients, such as appropriate care and covering of wounds and lesions, practicing good personal hygiene, and washing hands often both at home and in the community. Encourage them to use hand sanitizer wipes in the supermarket to disinfect shopping cart handles.
• Be a positive role model in your community.

MRSA spreads easily from person to person through skin contact. The bacterium can live for weeks on inanimate objects, such as overbed tables, light switches, side rails, call lights, uniforms and other clothing, medical equipment, and plastic.

What’s more, anyone can become a MRSA carrier, meaning he or she is colonized with the pathogen but doesn’t become ill. Although the relationship between colonization and infection isn’t completely understood, it’s associated with certain factors of both the host and the S. aureus strain.

Who’s at highest risk?

Today, you’re most likely to see hospital-acquired S. aureus strains among patients who’ve been readmitted with a known (previously diagnosed) infection, those who’ve been infected and diagnosed during their current hospitalization, and those discharged after an infection.

Risk facts for HA-MRSA include:

• prolonged hospital stay or residence in a long-term care facility
• stay in an intensive care or burn unit
• major underlying chronic illness
• invasive procedures or devices
• recent or intensive antibiotic therapy
• age extreme (very young or very old).

What you need to do

Your main role related to MRSA is to protect the public from it—patients, family members, friends, and others with whom you’re in contact—through rigorous infection control practices. Nursing actions include:

• preventing MRSA transmission in the healthcare setting
• using good personal hygiene
• always wearing clean clothes to work
• observing CDC standard precautions with all patients
• performing strict hand washing between patients—both before and after contact (possibly the single most effective weapon against MRSA)
• wearing gloves and other protective barriers when anticipating exposure to blood, body fluids, or pathogens
• decontaminating patient equipment or items in the patient environment likely to be contaminated with infectious body fluids or pathogens
• observing CDC contact precautions for patients with confirmed MRSA
• keeping your hands away from your face at work
• avoiding artificial fingernails when working in patient care areas
• advocating for specific workplace policies regarding return-to-work and fitness-for-duty for hospital staff members infected with or carrying MRSA (particularly those providing direct patient care)
• understanding the role of patient placement in limiting infection transmission (for example, placing MRSA patients in private rooms or cohorting MRSA patients)
• being aware that staff found to be MRSA carriers may experience stigma in the workplace.

One author recommends that personnel with draining skin lesions consistent with staphylococcal infection be barred from patient contact or food handling until the lesions have been cultured and a definitive diagnosis has been made. Healthcare workers in whom the infection has been confirmed should receive antibiotics and be barred from returning to their usual duties until the infection resolves. However, carriers need not be barred from patient care or food handling unless these activities have been epidemiologically linked to disease transmission.

HA-MRSA incidence in healthcare settings continues to rise. All healthcare workers need to stay abreast of infection control protocols and procedures and be vigilant in implementing them to help interrupt the transmission cycle of this potentially deadly disease.

Editor’s note: A recent Duke University study found MRSA infections have declined steadily since 2005, while Clostridium difficile infections have risen since 2007. Watch for an upcoming article on C. difficile infections in American Nurse Today.

Teresa Ellis Jarnagin is an assistant professor in the School of Nursing at Mississippi College in Clinton.

Selected references

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Tisinger C. Empowering your patients in the fight against methicillin-resistant Staphylococcus aureus. J Am Acad Nurse Pract. 2008;20(4):204-211.

Wood D, Hansen S. Media hype over MRSA creates opportunity for education. Nurse.com. November 19, 2007. http://news.nurse.com/apps/pbcs.dll/article?AID=2007312030024. Accessed April 5, 2010.