Dissemination of antibiotic-resistant enterococci within the ward environment: The role of airborne bacteria and the risk posed by unrecognized carriers.
Am J Infect Control. 2012 Jun 14;
Authors: Muzslay M, Moore G, Turton JF, Wilson AP
Abstract
BACKGROUND: Colonized or infected patients pose a significant risk to noncolonized patients occupying the same room. The aim of this study was to investigate how far Enterococcus spp can spread from isolated and nonisolated patients. METHODS: Conventional microbiological methods were used to recover enterococci from the air and from 62 high-contact sites located within the near-patient and wider ward environment. Samples were collected twice weekly for 17 weeks. The similarity between isolates was determined via pulsed-field gel electrophoresis. RESULTS: Vancomycin-susceptible enterococci (VSE) were recovered from 352 of 2,046 environmental surfaces (17.2%) and from 27 of 66 air samples (40.9%). During study week 14, VSE was recovered from 75 of the 124 surfaces sampled, representing 21.3% of all VSE-positive sites. A gentamicin-resistant VS Enterococcus faecium clone was recovered in high numbers from the air (>100 cfu/m(3)) and from surfaces throughout a 4-bed bay. The same clone was recovered from an adjacent isolation room as well. A total of 55 surfaces were contaminated with vancomycin-resistant enterococci (VRE). The environment of 2 isolated patients accounted for 85% of contaminated sites. Neither patient was known to be VRE-positive. CONCLUSIONS: Unrecognized colonization and/or the aerosolization of enterococci together with inadequate cleaning can lead to heavy, widespread, and persistent environmental contamination. All pose a significant risk for acquisition of antibiotic-resistant enterococci.
PMID: 22704685 [PubMed - as supplied by publisher]