“Enterococcus faecium is one of the leading causes of healthcare-associated infections in immunocompromised and critically ill patients,” Beth Blane, MSc, notes. “E faecium has a propensity to accumulate resistance to multiple antibiotics, with resistance to vancomycin limiting treatment choices to two or three lastresort antibiotics. Underpinning the success of vancomycinresistant E faecium (VRE) as a nosocomial pathogen is its ability to persist in hospital environments, which can act as reservoirs for transmission between patients.”
Previous work by Blane and colleagues showed that VRE strains with a high propensity to spread between patients were frequently found in communal spaces, particularly shared toilets and medical devices. Further, cleaning had only a limited, short-lasting impact in decreasing environmental contamination, Blane says. The results led the researchers to hypothesize that “drastic or innovative interventions would be required to curb VRE infections.”
For a study published in the Journal of Hospital Infection, Blane, Theodore Gouliouris, PhD, MD, and colleagues examined the impact of an established cardiothoracic hospital moving to a new site with nearly 100% single-occupancy rooms on the rates of environmental contamination and infection/colonization by VRE. Investigators performed prospective environmental surveillance for VRE at five time points, once in the original building and four times in the new building. They calculated incidence rate ratios (IRRs) of VRE infection/ colonization for the 1-year period before and after the hospital move, comparing the results with a nearby hospital.
VRE Carriage/Infection Rates Decrease in Year 1
The first environmental screen conducted at the original hospital revealed a VRE positivity rate of 29%, according to the study results. The subsequent four screenings in the new location showed a substantial reduction in positivity (1% to 6%; P<0.001). VRE infection/colonization rates were reduced by almost half in the new location (IRR, 0.56; 95% CI, 0.38-0.84) compared with the original location.
“The use of single-occupancy rooms was associated with a substantial reduction in levels of VRE contamination in the environment,” Blane says. “We detected an immediate and marked reduction in levels of VRE contamination in the environment that was sustained for 6 months of study follow-up.”
The decrease in VRE carriage/infection stood in “stark contrast to a neighboring hospital, where rates increased during the same period,” Blane notes (Figure). “Analysis of whole-genome sequencing data showed that there had been some carryover of clones between the old and new location, but [this] was consistent with reduced transmission in the new hospital.”
Environment Important for Preventing Infection
The findings illustrate “the importance of the built environment” in limiting contamination and transmission of VRE, especially using segregated beds, ensuite facilities, and new ventilation systems, according to Dr. Gouliouris.
“Single-occupancy rooms represent a ‘horizontal’ infection control intervention that has the potential to impact not only VRE and other multidrug-resistant pathogens, but also respiratory and gastrointestinal viral spread in hospitals,” he says. “Infectious disease specialists are ideally placed to understand these risks and should be actively involved in the design and planning of new hospitals.”
Further, Dr. Gouliouris notes that antimicrobial resistance is mainly due to a lack of novel therapeutics that are needed to counter a “pressing” public health crisis. VRE, which is often seen in the most vulnerable of hospitalized patients, is “no exception,” he continues.
“Future research is needed to design novel drugs and therapeutics active against this pathogen. At a basic level, there is a lack of understanding about what drives the success of super-spreading clones of VRE that would enable innovative decontamination or material design with antibacterial properties. Finally, the cost-effectiveness of single-occupancy hospital rooms in reducing healthcare-associated infections should be reassessed in the context of operational costs of emerging pandemics and increasing antimicrobial resistance threats.”
