Lethal 'superbug' on the rise

WASHINGTON, Nov. 30 (UPI) -- The community-associated strain of Methicillin-resistant Staphylococcus aureus is a far greater threat than previously considered, U.S. researchers say.

Ramanan Laxminarayan, principal investigator for Extending the Cure, a project of the think-tank Resources for the Future in Washington that examines policy solutions for the problem of antibiotic resistance, said the "superbug" poses a far greater health threat than previously known and is making its way into hospitals.

The deadly infection-causing bacteria, easily picked up in fitness centers, schools and other public places, is resistant to most common antibiotics.

Most MRSA infections occur in hospitals or other healthcare settings -- health care-associated MRSA -- but community-associated MRSA occurs among otherwise healthy people in the wider community.

The researchers analyzed data from more than 300 microbiology labs serving U.S. hospitals and found a seven-fold increase in the proportion of "community-associated" strains of MRSA in outpatient hospital units from 1999-2006.

The researchers found that the proportion of MRSA increased more than 90 percent among outpatients with staph and now accounts for more than 50 percent of all Staphylococcus aureus infections. The findings suggest this was due almost entirely to an increase in community-associated strains, which jumped from 3.6 percent of all MRSA infections to 28.2 from 1999-2006.

The findings are to be published in the December issue of Emerging Infectious Diseases.