The number of persons in the U.S. who have serious, and often termed “invasive,” infections with methicillin-resistant Staphylococcus-aureus (MRSA) is much greater than originally estimated, according to a study reported in the Oct. 17, 2007 issue of the Journal of the American Medical Association.
The study is the first to provide a population-based measure of invasive MRSA infections. Using results from nine U.S. metropolitan community sites participating in the Active Bacterial Core surveillance (ABCs)/Emerging Infections Program Network from July 2004 to December 2005, researchers at Centers for Disease Control and Prevention (CDC) studied thousands of MRSA infections. The scientists found that in about 27 percent of the cases, persons got the infections while patients in hospitals. About 14 percent got the infection in the community. And about 58 percent got the infection after a healthcare encounter, such as hospitalization or surgical procedure. “In the community Staphylococcal infections, including MRSA, generally start as red bumps or boils,” says study co-author Susan Ray, MD, associate professor of Medicine at Emory University School of Medicine, and co-author on the report. These can quickly turn into deep, painful abscesses that require surgical drainage. A small proportion of patients with MRSA skin abscesses will develop invasive disease, such as the infections noted in the study.” MRSA accounts for the most frequent cause of skin and soft tissue infections presenting to emergency rooms in the U.S. In hospitalized patients, MRSA has been a problem since the 1960s and is associated with greater lengths of stay, higher death rates and increased costs. “These infections were mostly seen in hospital settings but that is changing as we are beginning to see more community onset cases – and what that means is these old diseases are learning new tricks, essentially becoming drug resistant,” say Dr. Ray, associate hospital epidemiologist at Grady Health System in Atlanta. The study was funded through the Emerging Infections Program, National Center for Preparedness, Detection, and Control of Infectious Diseases, Coordinating Center for Infectious Diseases, CDC. (Source: Journal of the American Medical Association : Juliette Merchant : Emory University : December 2007)