An analysis of data from 2005 through 2008 of nine metropolitan areas in the U.S. indicates that healthcare-associated invasive methicillin-resistant Staphylococcus aureus (MRSA) infections decreased among patients with infections that began in the community or in the hospital, according to a study in the Aug. 11 issue of JAMA.
An estimated 1.7 million healthcare-associated infections (HAIs) are associated annually with 99,000 deaths in U.S. hospitals. A multidrug-resistant organism that has received much attention is MRSA, and preventing healthcare-associated MRSA infections has become a goal for public health agencies and policy makers, with prevention programs increasingly common in health care settings. Whether there have been changes in MRSA infection incidence as these programs become established has not been known, according to background information in the article.
Alexander J. Kallen, MD, MPH, of the Centers for Disease Control and Prevention (CDC), and colleagues used a population-based surveillance system to evaluate the incidence of invasive healthcare-associated MRSA infections from 2005 through 2008 in nine metropolitan areas covering a population of approximately 15 million persons. All reports of laboratory-identified episodes of invasive (from a normally sterile body site such as the bloodstream) MRSA infections were evaluated and classified based on the setting of the positive culture and the presence or absence of healthcare exposures.
Overall, the participating surveillances sites reported 21,503 cases of invasive MRSA infections for the years 2005 through 2008, with 17,508 cases either hospital-onset or healthcare-associated community-onset. Most healthcare-associated infections (15,458 [88 percent]) involved a positive blood culture and were classified as a bloodstream infection (BSI).
“The modeled incidence, adjusted for age and race, of hospital-onset invasive MRSA infections significantly decreased 9.4 percent per year from 2005 through 2008; while there was a significant 5.7 percent decrease per year in the modeled incidence of healthcare-associated community-onset infections. This would equate to about a 28 percent decrease in all hospital-onset invasive MRSA infections and about a 17 percent decrease in all invasive healthcare-associated community-onset infections over the four-year period,” the authors write.
