Screening for Methicillin-Resistant Staphylococcus Aureus (MRSA) Executive Summary

Methicillin-resistant Staphylococcus aureus (MRSA) emerged as a clinically relevant human pathogen more than five decades ago.1 The virulent bacterium was first detected in hospitals and other health care facilities where vulnerable hosts, frequent exposure to the selective pressure of intensive antimicrobial therapy, and the necessity for invasive procedures created a favorable environment for dissemination. MRSA emerged as an important cause of healthcare-associated infections, particularly central line–associated bloodstream infection, ventilatorassociated pneumonia, and surgical site infection (SSI). Despite the adoption of infection-control measures, the incidence of MRSA infection at most U.S. hospitals steadily increased for many years,2 but it is now decreasing.3-6 Burton and colleagues4 found a 49.6-percent decrease in the overall incidence of MRSA central line– associated bloodstream infection in U.S. intensive care units (ICUs) from 1997 to 2007. In a study of nine U.S. metropolitan areas, Kallen and colleagues6 found a reduction in the incidence rate of hospital-onset invasive MRSA infections of 9.4 percent per year from 2005 to 2008 (95% confidence interval [CI], 14.7 to 3.8%; p=0.005). Effective Health Care Program