Decontamination of the Environment
That VRE can remain viable on inanimate surfaces from seven days to two months has already
been established (138,145,146). In addition to hard surfaces, upholstered surfaces in hospitals
can be contaminated with VRE (174). VRE were recovered at 72 hours and one week after
inoculation to an upholstered surface. VRE were also recovered from 3 of 10 seat cushions that
were cultured in the room of a VRE patient. The authors state that an easily cleanable
nonporous material is the preferred upholstery in hospitals.
Extensive cultures of environmental surfaces in rooms of patients colonized with VRE in an
MICU and a burn ICU identified contaminated surfaces in 12% and 13.5%, respectively (135,138).
It has also been shown that at least one environmental surface was positive in the rooms of 63% to
92% of patients colonized with VRE (135,141). Five studies have demonstrated that VRE are easily
transferred to gloves or hands of HCWs after contact with the environment (101,140–143). In one
of the latter studies, VRE were transferred from a culture-positive site to a culture-negative site in
10.6% of the opportunities (143). VRE were transferred from patient to environment and from
environment to patient. VRE were transferred from sites with low-density contamination or
colonization (cultured from broth only) 69% of the time. Room contamination by VRE has been
shown to be an important risk factor for colonization of patients (175,176).
The effectiveness of decontamination of the environment depends on the method used.
In one study, the investigators observed that cleaning environmental surfaces with a cleaning
rag sprayed with a quaternary ammonium disinfectant was significantly less effective than
dipping the cleaning rag into a bucket of the same disinfectant, drenching all surfaces,
allowing the surfaces to remain wet for 10 minutes, and then wiping the surfaces dry with a
clean towel (177). The authors referred to the latter as the bucket method. Using the method in
which the disinfectant was sprayed on the cleaning rag took 2.8 applications to eradicate VRE
from environmental surfaces compared with one application using the bucket method. In
addition to a greater efficiency at removing VRE from surfaces, the bucket method also cost
less than the method of spraying disinfectant on a cleaning rag. Based on this study, the bucket
method is the preferred method for decontaminating environmental surfaces.
In another study investigators examined the elements of environmental cleaning to
determine whether changes in cleaning products, cleaning procedures, or performance of
cleaning personnel would lead to more effective cleaning of the environment (178). The
authors noted that the performance of cleaning personnel was the most important factor in the
effective decontamination of the environment. The effectiveness of cleaning personnel
performance was related to the number of environmental sites cleaned. The investigators
noted a decrease of 6% in prevalence of VRE with every 10% increase in percentage of sites
cleaned after adjustment for other factors.
Hand Hygiene
Excellent hand hygiene must always be practiced for the prevention of nosocomial infections,
but it is particularly important for providing effective isolation of patients with VRE. Given the
frequent contamination of gloved and ungloved hands of HCWs in contact with VRE-
colonized patients and environmental surfaces, excellent hand hygiene must be an integral
part of barrier precautions for VRE (140–142). After patient contact, hands should be washed
with an antiseptic-containing soap or an alcohol hand rub should be applied.
Colonization of HCWs
Colonization of HCWs with VRE has not been reported in the literature during outbreaks of VRE
infection and colonization. A study of 55 stool specimens from HCWs in a hospital, where 15% of
enterococci were VRE found that all cultures of stool specimens were negative for VRE (179). The
authors concluded that colonization resistance was sufficient to prevent colonization of HCWs’
gastrointestinal tracts in the absence of acute illness or severe underlying comorbidities.
Antimicrobial Agents
Antimicrobial agents have been identified as risk factors for acquisition of VRE as shown in
Tables 4 and 5. Vancomycin has been considered as a risk factor for acquisition of VRE, but
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