Explaining the Virulence of CA-MRSA

In vitro studies suggest that the virulence of the USA300 strain stems from increased expression of core staphylococcal genomic elements.

Community-associated methicillin-resistant Staphylococcus aureus (MRSA) — particularly the extremely infectious USA300 strain — is a major public health concern in the U.S. But why is this strain so virulent? Although some studies have implicated Panton-Valentine leukocidin (PVL), the results have been conflicting (JW Infect Dis Mar 14 2007 and Nov 29 2006). To better understand the evolution of USA300’s virulence, investigators analyzed the major MRSA strains of the clonal complex 8 (CC8) lineage, from which USA300 arose.

Initial sequence analysis of housekeeping and surface protein–encoding genes from six CC8 S. aureus strains indicated that USA300 evolved from a USA500 clone already present in community and hospital settings in the U.S., …

Reviewing Author

Richard T. Ellison III, MD

Disclosures

Consult/Advisory BoardAcurx Pharmaceuticals, LLC;

Grant/Research SupportDoctors Company Foundation, Massachusetts Department of Public Health

Richard T. Ellison III, MD

Disclosures

Consult/Advisory BoardAcurx Pharmaceuticals, LLC;

Grant/Research SupportDoctors Company Foundation, Massachusetts Department of Public Health