MRSA 'superbug' gaining ground

August 20, 2007

Prevalence of the methicillin-resistant Staphylococcus aureus (MRSAs) in U.S. healthcare facilities is 8 to 11 times greater than previous estimates.

Kevin Garey, Pharm.D., assistant professor, University of Houston College of Pharmacy, with research interests in infectious diseases (ID), isn't at all surprised with the study's findings. In most hospitals, at least 60% of all S. aureus isolates are MRSA, and it can be 70% or 80%, he said. "We've been battling this issue for at least half a decade."

In addition to healthcare-acquired MRSA data, the APIC study includes data on community-acquired MRSA, which usually causes skin and soft tissue infections, and which Garey sees as a major concern for hospitals. "In the past couple of years, the incidence of community-acquired MRSA has been very high and growing. Here in Houston, the rates of community-acquired MRSA could be higher than 50% of patients coming in with a staph infection. So it's a new world, and we have to think of MRSA in hospitals in places we haven't thought of before-such as the emergency department."

Owens agreed that community-acquired MRSA is likely contributing to the substantial increase in MRSA rates, and described several scenarios:

"But we're still seeing the old hospital-type MRSAs increasing in numbers as well," he added.

Another issue, according to Garey, is the ongoing debate of when to use newer, more expensive antibiotics or the old gold standard, "which has been vancomycin for 40 years." He pointed to antibiotic stewardship programs as perhaps the best avenue for hospitals. "These programs are responsible for appropriate use of antibiotics."

Owens helped write the guidelines for starting such programs that were issued in January 2007 by the Infectious Diseases Society of America (IDSA) and the Society for Healthcare Epidemiology of America (SHEA). The guidelines can be found at http://www.guideline.gov/summary/summary.aspx?doc_id=10482&nbr=5505.