Do infection control measures work for methicillin-resistant Staphylococcus aureus?
OBJECTIVE: To review evidence regarding the effectiveness of control measures in reducing transmission of methicillin-resistant Staphylococcus aureus (MRSA) in hospitals. DESIGN: Literature review and surveillance cultures of hospitalized patients at high risk for MRSA colonization or infection. SETTING: A 500-bed, university-affiliated, community teaching hospital. RESULTS: The percentage of nosocomial S. aureus infections caused by MRSA increased significantly between 1982 and 2002, despite the use of various isolation and barrier precaution policies. The apparent ineffectiveness of control measures may be due to several factors including the failure to identify patients colonized with MRSA. For example, cultures of stool specimens submitted for Clostridium difficile toxin assays at one hospital found that 12% of patients had MRSA in their stool, and 41% of patients with unrecognized colonization were cared for without using barrier precautions. Other factors include the use of barrier precaution strategies that do not account for multiple reservoirs of MRSA, poor adherence of healthcare workers (HCWs) to recommended barrier precautions and handwashing, failure to identify and treat HCWs responsible for transmitting MRSA, and importation of MRSA by patients admitted from other facilities. Control programs that include active surveillance cultures (ASCs) of high-risk patients and use of barrier precautions have reduced MRSA prevalence rates and have been cost-effective. Using a staged approach to implementing ASCs can minimize logistic problems. CONCLUSION: MRSA control programs are effective if they include ASCs of high-risk patients, use of barrier precautions when caring for colonized or infected patients, hand hygiene, and treating HCWs implicated in MRSA transmission.