Physician's Weekly Article - Preventing MRSA Transmission

       New recommendations from infectious disease experts aim to help clinicians prevent common healthcare-associated infections. Practical recommendations are provided to assist acute care hospitals in efforts to prevent the transmission of MRSA.

      The number of hospital-associated Staphylococcus aureus infections that are caused by methicillin-resistant strains of the bacteria has steadily increased in hospitals and ICUs throughout the United States over the past several decades. In 2004, data from the CDC showed that MRSA accounted for nearly two-thirds of all S aureus infections in hospitals. Although efforts have been made to reduce the burden of MRSA in various healthcare settings and to prevent nosocomial MRSA transmission and infection, many patient groups continue to be at risk for these infections. “MRSA hospital-associated infections (HAIs) have been associated with significant morbidity and mortality,” says David P. Calfee, MD, MS. “Patients with MRSA infection also spend a significantly longer time in the hospital and have much higher hospital costs.”

      In 2008, a task force appointed by the Society for Healthcare Epidemiology of America and the Infectious Diseases Society of America created a concise compendium of recommendations for the prevention of common HAIs, including MRSA. The recommendations, published in the October 2008 supplement to Infection Control and Hospital Epidemiology, were designed to help hospitals focus and prioritize their efforts in implementing evidence-based prevention practices. “The recommendations address key issues surrounding the problem of MRSA transmission,” says Dr. Calfee, who was on the panel that created the compendium recommendations.

      Substantial Risks

      Several factors have been identified in the compendium recommendations as key contributors to the higher morbidity and mortality rates associated with MRSA, as compared with those associated with methicillin-susceptible S aureus infections. Delays in the initiation of effective antimicrobial therapy, less-effective antimicrobial therapy for infections due to resistant strains, and higher severity of underlying illness may all play a role.

      Studies have shown that many MRSA-colonized patients will subsequently develop a MRSA infection. In people colonized with MRSA, the risk of developing a MRSA infection within 18 months after detection of MRSA colonization has been estimated at about 29%. Infections frequently include bacteremia, pneumonia, or soft tissue infections. “Clinicians must recognize traditional risk factors for healthcare-associated acquisition of MRSA,” says Dr. Calfee. “These include severe underlying illness or comorbid conditions, prolonged hospital stays, exposure to broad-spectrum antimicrobials, the presence of central venous catheters and other foreign bodies, and frequent contact with the healthcare system or healthcare personnel.” In addition, antimicrobial use provides a selective advantage for MRSA to survive, and transmission occurs largely through patient-to-patient spread.

      Several organizations have published evidence-based guidelines for preventing and controlling MRSA transmission (Table). While the recommendations are similar, they differ primarily with regard to the routine use of active surveillance testing to identify patients asymptomatically colonized with MRSA. The compendium recommendations provide practical suggestions for implementation and monitoring several of the prevention measures specified in the evidence-based guidelines (Figure). “Our hope is that these tools will assist MRSA transmission prevention efforts,” Dr. Calfee adds. “The recommendations are meant to be complementary to other general infection prevention measures, such as those used in ventilator-associated pneumonia and catheter-associated bloodstream bundles.”

      Establish an Effective Program

      According to the compendium recommendations, risk assessment is important when implementing prevention and monitoring strategies for MRSA. “A program should be in place to identify and track patients from whom MRSA has been isolated from clinical specimens or active surveillance testing,” says Dr. Calfee. “Implementation of a hand-hygiene compliance program is also paramount. To help reduce patient-to-patient spread of the organism within the hospital, contact precautions should be implemented for MRSA-colonized and MRSA-infected patients. Protocols and training should also be developed for cleaning and disinfecting environmental surfaces. Laboratory-based alert systems that immediately notify personnel about new MRSA-colonized or -infected patients can also be beneficial. An additional approach to limiting transmission is to utilize existing information regarding patients’ MRSA status at the time of readmission or transfer, prior to bed assignment, so that appropriate control measures (eg, contact precautions) can be instituted.”

      Dr. Calfee notes that healthcare personnel and patients with MRSA, as well as their families, should be educated about the organism. “It’s necessary that everyone has a good understanding of risk factors, routes of transmission, outcomes associated with the infection, prevention measures, and local epidemiology,” says Dr. Calfee. “For hospitals, the initial focus should be on compliance with hand-hygiene, contact precautions, and environmental disinfection. It’s also important to educate patients and their families about MRSA so that we can alleviate fears if actions are being taken. Approaches to patient education may include informational sheets in appropriate languages, patient education channels, websites, and video presentations. Using these tools can benefit patients and their families.”

      David P. Calfee, MD, MS, has indicated to Physician’s Weekly that he has previously served as a member of the speakers’ bureau for Enturia.