Infection control and prevention measures to reduce the spread of vancomycin-resistant enterococci in hospitalized patients: a systematic review and meta-analysis

Vancomycin-resistant enterococci (VRE) represent a major problem in healthcare settings worldwide. It is still unclear which is the most effective infection control and prevention (ICP) measure to reduce the spread of hospital-acquired VRE. Cochrane databases, MEDLINE, EMBASE and CINAHL were searched until June 2012 to find studies comparing wards/hospitals where ICP measures to prevent VRE transmission were investigated. In the absence of heterogeneity, a fixed-effects model was used to estimate the pooled risk ratio (RR). Study quality was assessed according to Cochrane Effective Practice and Organisation of Care (EPOC) criteria. The search strategy retrieved 549 studies and 9 studies (1 randomized clinical trial, 3 controlled clinical trials and 5 interrupted time series) with 30, 949 participants were included. The overall study quality was low. Implementation of hand hygiene was associated with a 47% decrease in the VRE acquisition rate (pooled RR 0.53, 95% CI 0.39-0.73, I(2) 26%) while contact precautions did not significantly reduce the VRE acquisition rate (pooled RR 1.08, 95% CI 0.63-1.83, I(2) 0%). Due to the low number of studies, meta-analysis was not applied for surveillance screening, environmental cleaning and antibiotic formulary interventions. No studies were available on the effectiveness of isolation and cohorting of patients and staff. Available evidence on the ICP measures to reduce VRE spread in adult hospitalized patients is poor. This systematic review suggests a significant role for the implementation of hand hygiene. Further studies with appropriate study design are urgently needed to define ICP measures able to reduce the acquisition of VRE among hospitalized patients.