1710. Environmental Contamination by Patients Infected or Colonized with MRSA or VRE: A multicenter study
Session: Poster Abstract Session: Role of the Healthcare Environment in HAIs
Saturday, October 5, 2013
Room: The Moscone Center: Poster Hall C
  • Infection Colonization Poster FINAL Submitted for printing 09-26-2013.pdf (527.8 kB)
  • Background: It is unknown whether the degree of environmental contamination differs between patients who are infected or simply colonized with methicillin-resistant Staphylococcus aureus (MRSA) or vancomycin-resistant Enterococcus (VRE).  In this multicenter study, we examined the difference in hospital room contamination between patients infected and colonized with MRSA or VRE.

    Methods: A convenience sample of 49 rooms of patients infected or colonized with MRSA or VRE (target organisms) at Duke University Medical Center (n=8) and the University of North Carolina Health Care (n=41) were tested from 7/21/2009 to 2/29/2012.  5 to 10 high-touch surfaces were sampled after patient discharge but prior to terminal room cleaning.  Total colony forming units (CFUs) of MRSA or VRE per room and per surface were calculated.  Standard descriptive statistics were used; median differences in room contamination of target organisms between infected and colonized patients were compared using Wilcoxon rank-sum tests.

    Results: 33 (67%) patients were colonized with either MRSA or VRE, 15 (31%) patients had infections, and 1 infection status was unknown.  19 (39%) patients were colonized or infected with MRSA and 30 (61%) patients were colonized or infected with VRE.  43 (88%) patients had 1 anatomic site of colonization/infection; 5 (10%) had 2 sites.  1073 total environmental cultures were taken from 27 floor and 22 ICU rooms.  Infected patients stayed in the room longer (median 16.4 days, IQR 4-20) than colonized patients (median 7.0 days, IQR 4-16; p=0.28), yet the median total target CFUs per room was higher for colonized patients (25, IQR 0-106) than infected patients (0, IQR 0-29; p-value=0.03); 24 (73%) colonized rooms had >=1 environmental site positive for MRSA or VRE compared with 5 (33%) infected rooms (p<0.001).  There were no significant differences in median CFUs when data were analyzed by organism type, by number of anatomic sites colonized/infected, by room type, or by locations that were sampled within rooms.

    Conclusion: To our surprise, environmental contamination with MRSA or VRE was as high or higher in rooms with colonization as in rooms with infection.  Adequate cleaning techniques are needed to prevent bacteria from contaminating room surfaces in patients that are colonized or infected with organisms like MRSA and VRE.

    Lauren Knelson, MSPH1, David A. Williams, RN, BSN, IP2, Maria Gergen2, William Rutala, PhD, FSHEA2, David J. Weber, MD, MPH, FIDSA, FSHEA2,3, Daniel J. Sexton, MD, FIDSA4,5, Deverick J. Anderson, MD, MPH1,5 and CDC Prevention Epicenters Program, (1)Division of Infectious Diseases, Duke University Medical Center, Durham, NC, (2)Department of Hospital Epidemiology, University of North Carolina Health Care, Chapel Hill, NC, (3)Division of Infectious Diseases, University of North Carolina At Chapel Hill, Chapel Hill, NC, (4)Duke University Medical Center, Durham, NC, (5)Duke Infection Control Outreach Network, Duke University Medical Center, Durham, NC


    L. Knelson, None

    D. A. Williams, None

    M. Gergen, None

    W. Rutala, None

    D. J. Weber, Pfizer: Consultant and Speaker's Bureau, Consulting fee and Speaker honorarium
    Merck: Consultant and Speaker's Bureau, Consulting fee and Speaker honorarium

    D. J. Sexton, None

    D. J. Anderson, None

    Findings in the abstracts are embargoed until 12:01 a.m. PST, Oct. 2nd with the exception of research findings presented at the IDWeek press conferences.