In the 1930s, medications were discovered that killed infective organisms known as Staphylococcus aureus, or staph. Staphylococcus aureus is alive and well today, however, being a common bacteria found in the nose and on healthy skin. MRSA, methicillin-resistant Staphylococcus aureus, which is immune to penicillin-like drugs and several other antibiotics, became a problem by the end of the 1970s in veteran's hospitals and burn units. Two strains of MRSA emerged: hospital-acquired (HA-MRSA) and community-acquired (CA-MRSA). In the 1990s, CA-MRSA gained prevalence in nursing homes in the United States. Now, otherwise healthy individuals are at risk as CA-MRSA infections become epidemic.
Risk
Those who become infected with HA-MRSA also have underlying health problems. However, CA-MRSA is becoming a more serious problem, according to Robert Moellering, M.D., professor of medical research at Harvard Medical School. Frequently, the infection manifests as a boil requiring routine cultures, surgical drainage and new, more expensive drug therapies. Skin barrier disruption is the greatest risk for MRSA skin and soft tissue invasion; eczema, scrapes, rashes and wounds allow the germs access to the body. A family history of infections or boils could be evidence of contagious MRSA. CA-MRSA may be carried into hospitals by visitors. Newborns and postpartum women are at risk. People who are obese, play contact sports, go to day care or who are of American Indian or African-American ethnicity are at increased risk. Adolescent boys have a greater incidence of MRSA infections than teens who are female.
Virulence
MRSA can cause a broad variety of infections, from superficial skin eruptions to urinary tract infections, life-threatening cellulitis, pneumonia, blood and surgical infections. MRSA can adapt to a variety of changing environmental conditions and can be carried by people with no symptoms, thus permitting widespread dissemination to many human hosts. MRSA has a remarkable propensity to develop resistance to multiple antimicrobial agents. According to Dr. Moellering, researchers have studied a whole series of interventions and found regular hand washing to be the best way to prevent the spread of MRSA.
Control
The Centers for Disease Control and Prevention provide guidelines for health care workers and the public designed to help control the spread of MRSA. Keep any break in the skin clean and covered until it heals. In public facilities, use towels as a barrier between seats and bare skin and do not use towels unless they are completely dry. Wash hands frequently or use hand sanitizer. Do not share personal items or clothing.
Those infected with MRSA may have a skin lesion that is red, swollen, tender and draining pus. The sore should be treated medically and covered, and dressings changed frequently, following instructions given by health care professionals.
References
- Medscape.com: Why Has MRSA Become Such a Successful Pathogen"; Carol J. Baker, MD; Robert C. Moellering Jr., M.D., March 30, 2009
- Centers for Disease Control and Prevention: Methicillin-Resistant Staphylococcus aureus (MRSA)
- "Clinical Infectious Diseases"; Modeling the Invasion of Community-Acquired Methicillin-Resistant Staphylococcus aureus into Hospitals"; Erica M.C., et.al., Feb. 1, 2009
