The effect of portable pulsed xenon ultraviolet light after terminal cleaning on hospital-associated Clostridium difficile infection in a community hospital

Limited reduction in Clostridioides difficile and Methicillin-Resistant Staphylococcus aureus with the use of an aerosolized hydrogen peroxide disinfection system in tertiary health care facilities in Alberta, Canada

BACKGROUND

Nonmanual room disinfection systems may reduce the transmission of infections. A variety of systems have emerged; however, a paucity of evidence exists to make an evidence-informed decision for the implementation of a specific system. Alberta Health Services assessed one of these systems.

METHODS

A quasi-experimental prepost design assessed an aerosolized hydrogen peroxide disinfection system on 6 units at 3 acute care facilities in Alberta. To assess clinical effectiveness an interrupted time-series analysis with Poisson distribution compared changes in hospital-acquired Clostridioides difficile infection (HA-CDI) and hospital-acquired Methicillin-resistant Staphylococcus aureus (HA-MRSA) between preintervention, intervention, and postintervention periods. To assess operational feasibility cleaning turnaround time, time to operate, and utilization were considered. A participatory research framework was used to understand the benefits and challenges of operationalization.

RESULTS

Incidence rate ratio (IRR) of HA-CDI decreased by 25.7% on FMC-A and 6.9% on RAH-B. Following withdrawal, the IRR of HA-CDI continued to decrease. IRR of HA-MRSA decreased by 25.0% on RAH-B. Following withdrawal, the IRR of HA-MRSA continued to decrease. None of the results were statistically significant. The average time to operate was 3.2 hours. Utilization was between 1.7% and 25.6%. Most staff reported benefits and challenges.

DISCUSSION

None of the changes observed in HA-CDI and HA-MRSA after the introduction of the aerosolized hydrogen peroxide system were statistically significant. While most respondents reported multiple benefits and challenges in using the system, the core challenge was delays in inpatient admissions due to the time operate the system.

CONCLUSION

Successful implementation of a nonmanual room disinfection system as an addition to standard cleaning and disinfection requires significant investment and must consider a variety of factors.

Hygiene requirements for cleaning and disinfection of surfaces: recommendation of the Commission for Hospital Hygiene and Infection Prevention (KRINKO) at the Robert Koch Institute

This recommendation of the Commission for Hospital Hygiene and Infection Prevention (KRINKO) addresses not only hospitals, but also outpatient health care facilities and compiles current evidence. The following criteria are the basis for the indications for cleaning and disinfection: Infectious bioburden and tenacity of potential pathogens on surfaces and their transmission routes, influence of disinfecting surface cleaning on the rate of nosocomial infections, interruption of cross infections due to multidrug-resistant organisms, and outbreak control by disinfecting cleaning within bundles. The criteria for the selection of disinfectants are determined by the requirements for effectiveness, the efficacy spectrum, the compatibility for humans and the environment, as well as the risk potential for the development of tolerance and resistance. Detailed instructions on the organization and implementation of cleaning and disinfection measures, including structural and equipment requirements, serve as the basis for their implementation. Since the agents for surface disinfection and disinfecting surface cleaning have been classified as biocides in Europe since 2013, the regulatory consequences are explained. As possible addition to surface disinfection, probiotic cleaning, is pointed out. In an informative appendix (only in German), the pathogen characteristics for their acquisition of surfaces, such as tenacity, infectious dose and biofilm formation, and the toxicological and ecotoxicological characteristics of microbicidal agents as the basis for their selection are explained, and methods for the evaluation of the resulting quality of cleaning or disinfecting surface cleaning are presented.

Beyond duodenoscope-transmitted infections: Analysis of surface bioburden and UV-C mitigation within a tertiary care endoscopy unit

BACKGROUND

An inpatient endoscopy unit is a care hub for patients from throughout the hospital and can be the site of health care-associated infections (HAIs). Shared surfaces and other nonmedical devices (keyboards) have been increasingly recognized as sites of pathogen transmission. Beyond standard cleaning of high-touch target areas, we queried whether the addition of automated devices delivering low-intensity doses of ultraviolet (UV)-C radiation could further reduce bioburden in an academic endoscopy unit.

METHODS

Bioburden on previously identified high-touch/communal surfaces was measured before and after the installation of automated, low-intensity UV-light emitting devices (UV Angel) that passively monitor and disinfect targeted surfaces with Ultraviolet-C light (UV-C) light.

RESULTS

High-touch sites (keyboards) had a baseline bacterial contamination of >80%, whereas individual procedure rooms and common areas had a >57% contamination rate. Following the implementation of automated UV-C light decontamination, bioburden was reduced on average by >91% at high-touch surfaces and within procedure rooms.

DISCUSSION/CONCLUSIONS

Nonsterile hubs of patient care could serve as sites of "silent" HAI transmission. We have identified high-touch surfaces within an endoscopy unit that have a high bioburden of bacterial contamination and demonstrated that the installation of passive, automated UV-C light disinfection devices can reduce bioburden significantly, possibly mitigating HAI transmission between patients.

Disinfection and sterilization: New technologies

BACKGROUND

Adherence to professional guidelines and/or manufacturer's instructions for use regarding proper disinfection and sterilization of medical devices is crucial to preventing cross transmission of pathogens between patients. Emerging pathogens (e.g., Candida auris) and complex medical devices provide new challenges.

METHODS

A search for published English articles on new disinfection and sterilization technologies was conducted by Google, Google scholar and PubMed.

RESULTS

Several new disinfection methods or products (e.g., electrostatic spraying, new sporicides, colorized disinfectants, "no touch" room decontamination, continuous room decontamination) and sterilization technologies (e.g., new sterilization technology for endoscopes) were identified.

CONCLUSIONS

These technologies should reduce patient risk.

úNo touch..Ñ methods for health care room disinfection: Focus on clinical trials

BACKGROUND

Hospital patient room surfaces are frequently contaminated with multidrug-resistant organisms. Since studies have demonstrated that inadequate terminal room disinfection commonly occurs, ..úno touch..Ñ methods of terminal room disinfection have been developed such as ultraviolet light (UV) devices and hydrogen peroxide (HP) systems.

METHODS

This paper reviews published clinical trials of ..úno touch..Ñ methods and ..úself-disinfecting..Ñ surfaces.

RESULTS

Multiple papers were identified including clinical trials of UV room disinfection devices (N.ß=.ß20), HP room disinfection systems (N.ß=.ß8), handheld UV devices (N.ß=.ß1), and copper-impregnated or coated surfaces (N.ß=.ß5). Most but not all clinical trials of UV devices and HP systems for terminal disinfection demonstrated a reduction of colonization/infection in patients subsequently housed in the room. Copper-coated surfaces were the only ..úself-disinfecting..Ñ technology evaluated by clinical trials. Results of these clinical trials were mixed.

DISCUSSION

Almost all clinical trials reviewed used a ..úweak..Ñ design (eg, before-after) and failed to assess potential confounders (eg, compliance with hand hygiene and environmental cleaning).

CONCLUSIONS

The evidence is strong enough to recommend the use of a ..úno-touch..Ñ method as an adjunct for outbreak control, mitigation strategy for high-consequence pathogens (eg, Candida auris or Ebola), or when there are an excessive endemic rates of multidrug-resistant organisms.

A systematic review of the germicidal effectiveness of ultraviolet disinfection across high-touch surfaces in the immediate patient environment

Background

There is not yet a consensus regarding the in-use effectiveness of ultraviolet irradiation (UV-C) as a supplementary tool for terminal room disinfection.

Aims and Objectives

To summarize and evaluate literature detailing the germicidal effectiveness of UV-C disinfection on high-touch surfaces in the patient environment.

Methods

A literature search was carried out utilizing PRISMA guidelines. Studies were included if intervention included UV-C after standard room disinfection in hospital rooms evaluated microbiologically by surface type.

Findings/Results

Twelve records met our criteria for inclusion. Studies predominantly focused on terminal disinfection of patient rooms, including five reports carried out in isolation rooms and three studies including operating room (OR) surfaces. Bedrails, remote controls, phones, tray tables, assist rails, floors, and toilets were the most commonly reported surfaces. Across study designs, surfaces, and room types, flat surfaces tended to showcase UV-C effectiveness best, particularly isolation room floors. In contrast, handheld surfaces (i.e., bed controls and assist bars) tended to show reduced efficacies (81-93%). In the OR, complex surfaces similarly demonstrated reduced UV-C effectiveness. Bathroom surfaces demonstrated 83% UV-C effectiveness overall, with surface characteristics uniquely impacted depending on the room type. Isolation room studies tended to include effectiveness comparison with standard treatment, reporting UV-C superiority most of the time.

Discussion

This review highlights the enhanced effectiveness of UV-C surface disinfection over standard protocols across various study designs and surfaces. However, surface and room characteristics do appear to play a role in the level of bacterial reduction.

The in situ efficacy of whole room disinfection devices: a literature review with practical recommendations for implementation

BACKGROUND

Terminal cleaning and disinfection of hospital patient rooms must be performed after discharge of a patient with a multidrug resistant micro-organism to eliminate pathogens from the environment. Terminal disinfection is often performed manually, which is prone to human errors and therefore poses an increased infection risk for the next patients. Automated whole room disinfection (WRD) replaces or adds on to the manual process of disinfection and can contribute to the quality of terminal disinfection. While the in vitro efficacy of WRD devices has been extensively investigated and reviewed, little is known about the in situ efficacy in a real-life hospital setting. In this review, we summarize available literature on the in situ efficacy of WRD devices in a hospital setting and compare findings to the in vitro efficacy of WRD devices. Moreover, we offer practical recommendations for the implementation of WRD devices.

METHODS

The in situ efficacy was summarized for four commonly used types of WRD devices: aerosolized hydrogen peroxide, H₂O₂ vapour, ultraviolet C and pulsed xenon ultraviolet. The in situ efficacy was based on environmental and clinical outcome measures. A systematic literature search was performed in PubMed in September 2021 to identify available literature. For each disinfection system, we summarized the available devices, practical information, in vitro efficacy and in situ efficacy.

RESULTS

In total, 54 articles were included. Articles reporting environmental outcomes of WRD devices had large variation in methodology, reported outcome measures, preparation of the patient room prior to environmental sampling, the location of sampling within the room and the moment of sampling. For the clinical outcome measures, all included articles reported the infection rate. Overall, these studies consistently showed that automated disinfection using any of the four types of WRD is effective in reducing environmental and clinical outcomes.

CONCLUSION

Despite the large variation in the included studies, the four automated WRD systems are effective in reducing the amount of pathogens present in a hospital environment, which was also in line with conclusions from in vitro studies. Therefore, the assessment of what WRD device would be most suitable in a specific healthcare setting mostly depends on practical considerations.

Effectiveness of Manual Terminal Cleaning Varies on High-Touch Surfaces Near the Operative Field

Background

Periprosthetic joint infection may result from pathogen to patient transmission within the environment. The purpose of this study is to evaluate the contamination level of selected high-touch surfaces in the operating room (OR) using a blacklight fluorescent marking system after a manual terminal clean.

Methods

Prior to the manual terminal clean, 16 high-touch surfaces were marked using a blacklight fluorescent gel. The marked areas were assessed the next morning for thoroughness of cleaning. Surfaces were categorized based on the average percent of the marks removed as “clean” (>75%), “partially clean” (26%-74%), or poorly cleaned (<25%). This process was repeated randomly 12 times. Terminal cleaning was done in the standard fashion, and the perioperative team was unaware of the initiation of this study.

Results

A total of 936 marks were analyzed. There was a significant difference in the number of marks completely clean (29.1%, 272/936) vs marks that were not touched (40.8%, 382/936), P < .001. Only the OR back table (75%) had a rating of clean. Partially clean areas included Mayfield table (72%), overhead lights (70.1%), infusion pump (61.1%), clock reset button (58.3%), table remote control (50%), tourniquet machine (50%), and the OR table (33.3%). Poorly cleaned surfaces included anesthesia medication cart (21.8%), door handles (20.8%), phone (16.7%), electrocautery unit (16.7%), foot pedal (16.7%), anesthesia cart (16.2%), nurses’ station (14.1%), and supply cabinet doors (6%).

Conclusions

Effectiveness of manual terminal cleaning varied greatly across surfaces. In general, surfaces further from the operative field were less likely to have markings removed.

Evaluation of an aerosolized hydrogen peroxide disinfection system for the reduction of Clostridioides difficile hospital infection rates over a 10 year period

BACKGROUND

Clostridioides difficile infections (CDI) cause significant morbidity and mortality in healthcare facilities worldwide. We examined the use of an aerosolized hydrogen peroxide (aHP) disinfection system for reduction of CDI rates.

METHODS

We conducted a retrospective analysis of CDI rates at an acute care facility over a 10-year period. The first 5-year period investigated the before and after implementation of an aHP system followed by another 5-year period of continued use on CDI rates.

RESULTS

The before and after period showed a reduction in CDI rates from 4.6 per 10,000 patient days down to 2.7 per 10,000 patient days after implementation (P < .001). The second study period for the continued aHP use exhibited a consistent decrease in CDI rates to 1.4 per 10,000 patient days at the end of the study.

CONCLUSIONS

The addition of a touchless aHP whole room disinfection system as part of terminal cleaning resulted in a significant reduction in CDI rates that have been sustained year after year.

A systematic review and meta-analysis of decontamination methods to prevent hospital environmental contamination and transmission of Clostridioidesdifficile

The current guidelines suggest that hospital rooms previously occupied with Clostridioides difficile infection (CDI) patients should be decontaminated with recommended decontamination methods because C. difficile can persist on surfaces despite adherence to the recommended procedures. Recently, ultraviolet (UV) light and hydrogen peroxide have increasingly been used as innovative decontamination methods. Hence, we conducted a systematic review and meta-analysis to investigate which decontamination methods are effective in reducing environmental C. difficile contamination. We systematically searched the EMBASE, PubMed, CINAHL, Scopus, and Ichushi until March 11, 2021. We evaluated the efficacy of decontamination methods in terms of the frequency of C. difficile contamination on high-touch surfaces in hospital rooms and the incidence of hospital-acquired C. difficile infection. Among the 15 studies retrieved in our meta-analysis, eight evaluated decontamination methods with the frequency of C. difficile detection among samples after disinfection procedures, and eight reported the number of hospital-acquired CDI cases. Pooled analysis indicated that hydrogen peroxide significantly reduced the frequency of environmental C. difficile contamination, compared with hypochlorite (odds ratios [OR]: 0.12; 95% confidence interval [CI]: 0.07-0.23). Additionally, hydrogen peroxide reduced the incidence of hospital-acquired CDI compared to other methods (OR: 0.52; 95% CI: 0.28-0.96). Decontamination with UV significantly reduced the incidence of hospital-acquired CDI compared to hypochlorite (OR 0.52, 95% CI 0.28-0.96). The use of hydrogen peroxide and UV can help prevent environmental C. difficile contamination and transmission in healthcare facilities.

Ultraviolet-C Light Evaluation as Adjunct Disinfection to Remove Multi-Drug Resistant Organisms

Background

Our objective was to determine if the addition of ultraviolet-C (UV-C) light to daily and discharge patient room cleaning reduces healthcare-associated infection rates of vancomycin-resistant enterococci (VRE) and Clostridioides difficile in immunocompromised adults.

Methods

We performed a cluster randomized crossover control trial in 4 cancer and 1 solid organ transplant in-patient units at the Johns Hopkins Hospital, Baltimore, Maryland. For study year 1, each unit was randomized to intervention of UV-C light plus standard environmental cleaning or control of standard environmental cleaning, followed by a 5-week washout period. In study year 2, units switched assignments. The outcomes were healthcare-associated rates of VRE or C. difficile. Statistical inference used a two-stage approach recommended for cluster-randomized trials with <15 clusters/arm.

Results

In total, 302 new VRE infections were observed during 45787 at risk patient-days. The incidence in control and intervention groups was 6.68 and 6.52 per 1000 patient-days respectively; the unadjusted incidence rate ratio (IRR) was 0.98 (95% confidence interval [CI], .78 − 1.22; P = .54). There were 84 new C. difficile infections observed during 26118 at risk patient-days. The incidence in control and intervention periods was 2.64 and 3.78 per 1000 patient-days respectively; the unadjusted IRR was 1.43 (95% CI, .93 − 2.21; P = .98).

Conclusions

When used daily and at post discharge in addition to standard environmental cleaning, UV-C disinfection did not reduce VRE or C. difficile infection rates in cancer and solid organ transplant units.

Can multidrug-resistant organisms become resistant to ultraviolet (UV) light following serial exposures? Characterization of post-UV genomic changes using whole-genome sequencing

OBJECTIVES

No-touch disinfection systems like xenon- or mercury-based ultraviolet (UV) are now commonly being used for hospital room disinfection. However, serial exposure to UV light can potentially lead to the development of bacterial resistance. We sought to determine whether UV resistance develops due to serial exposure to UV light using 3 epidemiologically important multidrug-resistant microbial strains.

METHODS

Methicillin-resistant Staphylococcus aureus (MRSA), carbapenemase-producing Klebsiella pneumoniae (KPC) and metallo-β-lactamase-producing Klebsiella pneumoniae (MBL) were serially exposed to 25 growth-irradiation cycles of UV produced by a xenon-based UV (Xe-UV) lamp for 5 minutes or a mercury-based UV (Hg-UV) lamp for 10 minutes. After each UV exposure cycle, the surviving colony-forming units (CFUs) were measured and compared with the initial inoculum of each cycle for each strain, respectively.

RESULTS

In each cycle, ˜1-10 million of MRSA, KPC, and MBL were used to test the effect of UV irradiation. Postexposure colony counts remained low (3-100 colonies) throughout the 25 serial exposures to both xenon- and mercury-based UV. The log-kill rate after each exposure showed no changes following UV disinfection by Xe-UV. The MRSA log-kill rate increased after repeated exposure to Hg-UV unlike KPC and MBL K. pneumoniae, which did not change. Whole-genome sequencing (WGS) analyses performed on these 3 strains demonstrated no significant genetic changes after multiple UV irradiation cycles.

CONCLUSIONS

Exposure of multidrug-resistant bacteria to UV produced from 2 different UV sources did not engender UV resistance after 25 serial exposures, as demonstrated by WGS analysis; thus, UV disinfection is unlikely to generate UV-resistant hospital flora.

Environmental Cleaning and Decontamination to Prevent Clostridioides difficile Infection in Health Care Settings: A Systematic Review

Objective

The aim of this systematic review was to examine the most effective and feasible methods for environmental cleaning and decontamination to prevent Clostridioides difficile infection (CDI) in health care settings.

Methods

A systematic search of the databases CINAHL and MEDLINE was conducted from 2008 to 2018 for English language articles with search terms including “Clostridium difficile,” and related medical subject headings, in combination with terms like “disinfection,” “decontamination,” and “no-touch decontamination.”

Results

Twelve studies and 2 systematic reviews were selected for inclusion in this review. The studies were primarily in hospitals (10/12) and used a before-after approach. The studied interventions included cleaning and decontamination with a chlorine-based agent (i.e., bleach; 2 studies), standard cleaning plus the use of hydrogen peroxide decontamination (3 studies), and standard bleach cleaning plus the use of ultraviolet light decontamination (6 studies), and there was 1 study about launderable bed covers. The interventions ranged in frequency, duration, and the area selected for cleaning and decontamination (e.g., all patient rooms versus only CDI patients’ rooms). Studies showed significant reductions in CDI associated with use of bleach (versus quaternary ammonium compound) and hydrogen peroxide decontamination after standard bleach cleaning (versus bleach cleaning alone). Four of 6 studies found significant reductions in CDI after the implementation of ultraviolet light decontamination after standard bleach cleaning.

Conclusions

The studied practices for environmental cleaning and decontamination were associated with significant decreases in facility-level CDI rates in most of the reviewed studies; however, study quality was low. Implementation challenges are worthy of further examination.

Systematic review on use, cost and clinical efficacy of automated decontamination devices

BACKGROUND

More evidence is emerging on the role of surface decontamination for reducing hospital-acquired infection (HAI). Timely and adequate removal of environmental pathogens leads to measurable clinical benefit in both routine and outbreak situations.

OBJECTIVES

This systematic review aimed to evaluate published studies describing the effect of automated technologies delivering hydrogen peroxide (H202) or ultra-violet (UV) light on HAI rates.

METHODS

A systematic review was performed using relevant search terms. Databases were scanned from January 2005 to March 2020 for studies reporting clinical outcome after use of automated devices on healthcare surfaces. Information collected included device type, overall findings; hospital and ward data; study location, length and size; antimicrobial consumption; domestic monitoring; and infection control interventions. Study sponsorship and duplicate publications were also noted.

RESULTS

While there are clear benefits from non-touch devices in vitro, we found insufficient objective assessment of patient outcome due to the before-and-after nature of 36 of 43 (84%) studies. Of 43 studies, 20 (47%) used hydrogen peroxide (14 for outbreaks) and 23 (53%) used UV technology (none for outbreaks). The most popular pathogen targeted, either alone or in combination with others, was Clostridium difficile (27 of 43 studies: 63%), followed by methicillin-resistant Staphylococcus aureus (MRSA) (16 of 43: 37%). Many owed funding and/or personnel to industry sponsorship (28 of 43: 65%) and most were confounded by concurrent infection control, antimicrobial stewardship and/or cleaning audit initiatives. Few contained data on device costs and rarely on comparable costs (1 of 43: 2%). There were expected relationships between the country hosting the study and location of device companies. None mentioned the potential for environmental damage, including effects on microbial survivors.

CONCLUSION

There were mixed results for patient benefit from this review of automated devices using H202 or UV for surface decontamination. Most non-outbreak studies lacked an appropriate control group and were potentially compromised by industry sponsorship. Concern over HAI encourages delivery of powerful disinfectants for eliminating pathogens without appreciating toxicity or cost benefit. Routine use of these devices requires justification from standardized and controlled studies to understand how best to manage contaminated healthcare environments.

Sustainable Waste Management for a City Multifloor Manufacturing Cluster: A Framework for Designing a Smart Supply Chain

This study focuses on integrated sustainable waste management (ISWM) within a city multifloor manufacturing (MFM) cluster. Manufacturing activities in residential areas of the urban environment and the associated generation of municipal production waste (MPW) are serious problems. The primary goal of this study is to design smart supply chain (SSC) scenarios for the shipment of MPW from a city MFM cluster under uncertainty. This paper presents a new model of the finite MPW generation capacity for a city MFM cluster on the basis of an analysis of its finite production capacity using the material flow analysis (MFA) methodology. The proposed model allows us to determine the number of transport fleet units needed for the implementation of various supply chain (SC) scenarios of MPW. To select the best scenario for MPW shipment in real time, the application of SSC and SSC management (SSCM) technologies is proposed. SSCM performance indicators are proposed which allow us to evaluate the efficiency of using vehicles for cluster MPW transportation. The numerical values of the SSCM performance indicators for various options regarding the handling of city MFM buildings using trucks are obtained. These evaluations form the basis for the decision-making and planning associated with the SSCs of MPW.

Potential of pulsed light technology for control of SARS-CoV-2 in hospital environments

The emergence of the SARS-CoV-2 infection and its potential transmission through touching surfaces in clinical environments have impelled the use of conventional and novel methods of disinfection to prevent its spreading. Among the latter, pulsed light may be an effective, non-chemical decontamination alternative. Pulsed light technology inactivates microorganisms and viruses by using high intensity polychromatic light pulses, which degrades nucleic acids and proteins. This review describes this technology, compiles and critically analyzes the evidence about the virucidal efficacy of pulsed light technology with view on its potential use against SARS-CoV-2 in touching surfaces in health-care facilities. The efficacy of pulsed light proved against many different kind of viruses allows to conclude that is a suitable candidate to inactivate SARS-CoV-2 as long as the required fluence is applied and the appropriated exposure to contaminated surfaces is guaranteed.

•

Pulsed light can inactivate many different types of viruses.

•

Its antimicrobial efficacy has been proved in different health care facilities.

•

Pulsed light produces fast inactivation and it is ecologically friendly.

•

Evidence shows that it should be effective for SARS-CoV-2 inactivation.

Efficacy of pulsed-xenon ultraviolet light on reduction of Mycobacterium fortuitum

Objectives

Hospitals and healthcare facilities rely largely on isolation and environmental disinfection to prevent transmission of pathogens. The use of no-touch technology is an accepted practice for environmental decontamination in medical care facilities, but little has been published about the effect of ultraviolet light generated by a portable pulsed-xenon device use on Mycobacteria. We used Mycobacterium fortuitum which is more resistant to ultraviolet radiation and less virulent than Mycobacterium tuberculosis, to determine the effectiveness of portable pulsed-xenon devices on Mycobacterium in a laboratory environment.

Methods

To determine the effectiveness of pulsed-xenon devices, we measured the bactericidal effect of pulsed-xenon devices on Mycobacterium fortuitum.

Results

In five separate experiments irradiating an average of 10⁶ organisms, the mean (standard deviation) log-kill at 5 min was 3.98 (0.60), at 10 min was 4.96 (0.42), and at 15 min was 5.64 (0.52).

Conclusions

Our results demonstrate that using pulsed-xenon devices is a highly effective modality to reduce microbial counts with this relatively ultraviolet germicidal irradiation-resistant mycobacterium in a time-dependent manner.

Understanding building-occupant-microbiome interactions toward healthy built environments: A review

Built environments, occupants, and microbiomes constitute a system of ecosystems with extensive interactions that impact one another. Understanding the interactions between these systems is essential to develop strategies for effective management of the built environment and its inhabitants to enhance public health and well-being. Numerous studies have been conducted to characterize the microbiomes of the built environment. This review summarizes current progress in understanding the interactions between attributes of built environments and occupant behaviors that shape the structure and dynamics of indoor microbial communities. In addition, this review also discusses the challenges and future research needs in the field of microbiomes of the built environment that necessitate research beyond the basic characterization of microbiomes in order to gain an understanding of the causal mechanisms between the built environment, occupants, and microbiomes, which will provide a knowledge base for the development of transformative intervention strategies toward healthy built environments. The pressing need to control the transmission of SARS-CoV-2 in indoor environments highlights the urgency and significance of understanding the complex interactions between the built environment, occupants, and microbiomes, which is the focus of this review.

Deactivation of SARS-CoV-2 with pulsed-xenon ultraviolet light: Implications for environmental COVID-19 control

Objectives:

Prolonged survival of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on environmental surfaces and personal protective equipment may lead to these surfaces transmitting this pathogen to others. We sought to determine the effectiveness of a pulsed-xenon ultraviolet (PX-UV) disinfection system in reducing the load of SARS-CoV-2 on hard surfaces and N95 respirators.

Methods:

Chamber slides and N95 respirator material were directly inoculated with SARS-CoV-2 and were exposed to different durations of PX-UV.

Results:

For hard surfaces, disinfection for 1, 2, and 5 minutes resulted in 3.53 log₁₀, >4.54 log₁₀, and >4.12 log₁₀ reductions in viral load, respectively. For N95 respirators, disinfection for 5 minutes resulted in >4.79 log₁₀ reduction in viral load. PX-UV significantly reduced SARS-CoV-2 on hard surfaces and N95 respirators.

Conclusion:

With the potential to rapidly disinfectant environmental surfaces and N95 respirators, PX-UV devices are a promising technology to reduce environmental and personal protective equipment bioburden and to enhance both healthcare worker and patient safety by reducing the risk of exposure to SARS-CoV-2.

Maximizing efficiency in a high occupancy setting to utilize ultraviolet disinfection for isolation rooms

BACKGROUND

Ultraviolet (UV) disinfection decreases nosocomial disease rates in acute care settings; effective program implementation is poorly understood. We developed a program to UV-disinfect rooms following discharge of patients in transmission-based precautions (TBP) and assessed its effect on hospital-acquired infection (HAI) rates.

METHODS

An isolation room housed a patient in any type of TBP. A priority room was an isolation room in TBP for multidrug resistant organisms or Clostridioides difficile infection. Percent rooms disinfected and HAI rates were calculated monthly. The two-robot program was started by Infection Prevention utilizing a single environmental services employee. Efficiency was increased by granting environmental services' personnel oversight, increasing coverage, and modifying shift-based goals. Our primary goal was disinfection of all discharged priority rooms. Our secondary goal was disinfection of all discharged isolation rooms.

RESULTS

The program achieved 6-month disinfection averages of 85.7% of isolation, and 87.7% priority rooms, respectively. Using a dedicated UV disinfection team and setting isolation room per shift goals improved coverage. HAI rates decreased by 16.2% following program implementation.

CONCLUSIONS

We implemented an effective UV disinfection program, and observed HAI reduction, by focusing on broad coverage and efficient deployment of assets without affecting patient flow or expanding the robot fleet.

Role of pulsed-xenon ultraviolet light in reducing healthcare-associated infections: a systematic review and meta-analysis

Pulsed-xenon-ultraviolet light (PX-UVL) is increasingly used as a supplemental disinfection method in healthcare settings. We undertook a systematic search of the literature through several databases and conducted a meta-analysis to evaluate the efficacy of PX-UVL in reducing healthcare-associated infections. Eleven studies were included in the systematic review and nine in the meta-analysis. Pooled analysis of seven studies with before-after data indicated a statistically significant reduction of Clostridium difficile infection (CDI) rates with the use of the PX-UVL (incidence rate ratio (IRR): 0.73, 95% CI 0.57–0.94, I² = 72%, P = 0.01), and four studies reported a reduction of risk of methicillin-resistant Staphylococcus aureus (MRSA) infections (IRR: 0.79, 95% CI 0.64–0.98, I² = 35%, P = 0.03). However, a further four trials found no significant reduction in vancomycin-resistant enterococci (VRE) infection rates (IRR: 0.80, 95% CI 0.63–1.01, I² = 60%, P = 0.06). The results for CDI and MRSA proved unstable on sensitivity analysis. Meta-regression analysis did not demonstrate any influence of study duration or intervention duration on CDI rates. We conclude that the use of PX-UVL, in addition to standard disinfection protocols, may help to reduce the incidence of CDI and MRSA but not VRE infection rates. However, the quality of evidence is not high, with unstable results and wide confidence intervals, and further high-quality studies are required to supplement the current evidence.

Clinical Issues-May 2020

Using Failure Modes and Effects Analysis to improve special-order implant procurement Key words: Failure Modes and Effects Analysis (FMEA), implant procurement, special-order implant, risk profile number (RPN), interdisciplinary teamwork. Heat stress among perioperative personnel Key words: heat stress, environmental conditions, task performance, surgical tasks, OR temperature. Venous thromboembolism prevention for bariatric surgery patients Key words: venous thromboembolism (VTE), prophylactic measures, bariatric surgery, risk factors, prevention protocol. Disinfecting case carts using ultraviolet light systems Key words: environmental cleaning, decontamination, case cart, ultraviolet (UV) light system, pulsed xenon.

Recurrence of Clostridium difficile infection in the Western Australian population

Clostridium difficile, the most common cause of hospital-associated diarrhoea in developed countries, presents major public health challenges. The high clinical and economic burden from C. difficile infection (CDI) relates to the high frequency of recurrent infections caused by either the same or different strains of C. difficile. An interval of 8 weeks after index infection is commonly used to classify recurrent CDI episodes. We assessed strains of C. difficile in a sample of patients with recurrent CDI in Western Australia from October 2011 to July 2017. The performance of different intervals between initial and subsequent episodes of CDI was investigated. Of 4612 patients with CDI, 1471 (32%) were identified with recurrence. PCR ribotyping data were available for initial and recurrent episodes for 551 patients. Relapse (recurrence with same ribotype (RT) as index episode) was found in 350 (64%) patients and reinfection (recurrence with new RT) in 201 (36%) patients. Our analysis indicates that 8- and 20-week intervals failed to adequately distinguish reinfection from relapse. In addition, living in a non-metropolitan area modified the effect of age on the risk of relapse. Where molecular epidemiological data are not available, we suggest that applying an 8-week interval to define recurrent CDI requires more consideration.

Development of a Pulsed Xenon Ultraviolet Disinfection Device for Real-Time Air Disinfection in Ambulances

Objectives

We have developed a pulsed xenon ultraviolet light-based real-time air disinfection system with rapid and effective disinfection by using high-intensity pulse germicidal UV. Disinfection of the ambulance's environment is critical in the prevention of infectious cross contamination.

Methods

In this study, a pulsed xenon ultraviolet light-based air disinfection system was established for real-time air disinfection in ambulances. In this system, a pulsed xenon ultraviolet (PX-UV) was used to generate broad-spectrum (200–320 nm), high-intensity ultraviolet light to deactivate and kill bacteria and viruses. The results showed that the use of PX-UV could be effective in reducing E. coli, Staphylococcus albus, and environmental pathogens level in ambulances (≥90% reduction in 30 mins).

Results

This device was relatively simple and easy to use and does not leave chemical residues or risk exposing patients and workers to toxic chemicals.

Conclusions

This appears to be a practical alternative technology to achieve automated air disinfection in ambulances.

Effect of pulsed xenon ultraviolet disinfection on methicillin-resistant Staphylococcus aureus contamination of high-touch surfaces in a Japanese hospital

BACKGROUND

The hospital environment is an important source of multidrug-resistant organisms such as methicillin-resistant Staphylococcus aureus (MRSA). Here, we evaluated the efficacy of pulsed xenon ultraviolet (PX-UV) disinfection in addition to manual cleaning in a Japanese hospital.

METHODS

Environmental samples were collected from inpatient rooms that had been occupied for at least 48 hours by patients infected or colonized with MRSA. High-touch surfaces from 11 rooms were sampled before and after manual cleaning and then after PX-UV disinfection. Changes in bacterial counts and in the number of aerobic bacteria (AB)- and MRSA-positive samples between sampling points were assessed. The time taken to complete PX-UV treatment of patient rooms was also recorded.

RESULTS

A total of 306 samples were collected. PX-UV disinfection resulted in a significant decrease in abundance of AB and MRSA (mean colony-forming units 14.4 ± 38.7 to 1.7 ± 6.1, P < .001 and 1.1 ± 3.9 to 0.3 ± 2.0, P < .001, respectively) and in the number of AB- and MRSA-positive samples (58.8%-28.4%, P = .001 and 19.6%-3.9%, P < .001, respectively) compared with manual cleaning. The median time of in-room use of the PX-UV device was 20 minutes.

CONCLUSIONS

The addition of PX-UV disinfection to the manual cleaning process significantly reduced AB and MRSA contamination of high-touch surfaces in hospital inpatient rooms.

Clinical and microbiological effect of pulsed xenon ultraviolet disinfection to reduce multidrug-resistant organisms in the intensive care unit in a Japanese hospital: a before-after study

Background

No-touch environmental disinfection using ultraviolet devices has been highlighted in the past several years to control the transmission of multidrug-resistant organisms (MDROs). However, its effectiveness in non-US healthcare settings is yet to be examined. This study aimed to evaluate the effectiveness of disinfection by portable pulsed xenon ultraviolet (PX-UV) devices in controlling transmission of MDROs in a non-US healthcare setting.

Methods

All patients admitted in the intensive care unit in a 629-bed tertiary referral hospital in Japan from August 2016 to February 2019 were enrolled. During the study period, PX-UV disinfection was added to manual terminal cleaning after every patient transfer/discharge. For microbiological evaluation, surfaces were selected for sampling by contact plates before/after manual cleaning and after PX-UV. After overnight incubation, colonies on the plates were counted.

Results

The incidence of newly acquired methicillin-resistant Staphylococcus aureus (MRSA) declined significantly (13.8 to 9.9 per 10,000 patient days, incidence rate ratio 0.71, p = 0.002), as well as that of newly acquired drug-resistant Acinetobacter (48.5 to 18.1, 0.37, p < 0.001). The percent reduction of the microbiological burden by manual cleaning was 81%, but a further 59% reduction was achieved by PX-UV.

Conclusions

PX-UV is effective in further reducing the microbial burden and controlling MDROs in a non-US healthcare setting.

An overview of automated room disinfection systems: When to use them and how to choose them

Conventional disinfection methods are limited by reliance on the operator to ensure appropriate selection, formulation, distribution, and contact time of the agent. Automated room disinfection (ARD) systems remove or reduce reliance on operators and so they have the potential to improve the efficacy of terminal disinfection. The most commonly used systems are hydrogen peroxide vapor (H₂O₂ vapor), aerosolized hydrogen peroxide (aHP), and ultraviolet (UV) light. These systems have important differences in their active agent, delivery mechanism, efficacy, process time, and ease of use. The choice of ARD system should be influenced by the intended application, the evidence base for effectiveness, practicalities of implementation, and cost considerations.

Network analysis of intra-hospital transfers and hospital onset clostridium difficile infection

OBJECTIVES

To explore how social network analysis (SNA) can be used to analyse intra-hospital patient networks of individuals with a hospital acquired infection (HAI) for further analysis in a geographical information systems (GIS) environment.

METHODS

A case and control study design was used to select 2008 patients. We retrieved locational data for the patients, which was then translated into a network with the SNA software and then GIS software. Overall metrics were calculated for the SNA based on three datasets and further analysed with a GIS.

RESULTS

The SNA analysis compared cases to control indicating significant differences in the overall structure of the networks. A GIS visual representation of these metrics was developed, showing spatial variation across the example hospital floor.

DISCUSSION

This study confirmed the importance that intra-hospital patient networks play in the transmission of HAIs, highlighting opportunities for interventions utilising these data. Due to spatial variation differences, further research is necessary to confirm this is not a localised phenomenon, but instead a common situation occurring within many hospitals.

CONCLUSION

Utilising SNA and GIS analysis in conjunction with one another provided a data-rich environment in which the risk inherent in intra-hospital transfer networks was quantified, visualised and interpreted for potential interventions.

Pulsed xenon ultraviolet and non-thermal atmospheric plasma treatments are effective for the disinfection of air in hospital blood sampling rooms

BACKGROUND AND OBJECTIVES

Non-thermal atmospheric plasma treatment and pulsed xenon ultraviolet (PX-UV) treatment are widely used in disinfection of hospital environments. However, their effectiveness has not been evaluated against a comparator. The objective of this study is to evaluate their effectiveness in the disinfection of pathogens in the air in hospital blood sampling rooms.

METHODS

Samples were taken from the air before and after disinfection with PX-UV and non-thermal atmospheric plasma. We counted bacterial colonies and identified the types of bacteria.

RESULTS

Non-thermal plasma treatment significantly reduced bacterial counts in the air, the median reduced from 1 before treatment to zero afterwards (p = 0.03). PX-UV treatment also significantly reduced bacterial counts in the air (p = 0.01), the median reduced from 1.5 before treatment to zero afterwards. Pathogens identified in the current study include nosocomial bacteria, such as Staphylococcus aureus, Staphylococcus epidermidis, and yeast.

CONCLUSION

Disinfection of blood sampling sites is essential in a health service department. The efficiency of PX-UV and non-thermal atmospheric plasma treatment are comparable in air disinfection.

Efficacy of pulsed-xenon ultraviolet light for disinfection of high-touch surfaces in an Ecuadorian hospital

Background

Hospital environment in patient care has been linked on healthcare-associated infections (HAI). No touch disinfection technologies that utilize pulsed xenon ultraviolet light has been recognized to prevent infection in contaminated environments. The purpose of this study was: 1) to evaluate the effectiveness of pulsed-xenon ultraviolet light (PX-UV) disinfection for the reduction of bacteria on environmental surfaces of Hospital General Enrique Garcés, and 2) to evaluate the in-vitro efficacy against multi-drug resistance microorganisms.

Methods

This was a quality-improvement study looking at cleaning and disinfection of patient areas. During the study, a total of 146 surfaces from 17 rooms were sampled in a secondary 329-bed public medical center. Microbiological samples of high-touch surfaces were taken after terminal manual cleaning and after pulsed xenon ultraviolet disinfection. Cleaning staff were blinded to the study purpose and told clean following their usual protocols. For positive cultures PCR identification for carbapenemase-resistance genes (blaKPC, blaIMP, blaVIM, and blaNDM) were analyzed and confirmed by sequencing. The total number of colony forming units (CFU) were obtained and statistical analyses were conducted using Wilcoxon Rank Sum tests to evaluate the difference in CFU between terminal manual cleaning and after pulsed xenon ultraviolet disinfection.

Results

After manual disinfection of 124 surfaces showed a total of 3569 CFU which dropped to 889 CFU in 80 surfaces after pulsed xenon disinfection (p < 0.001). Overall, the surface and environmental contamination was reduced by 75% after PX-UV compared to manual cleaning and disinfection. There were statistically significant decreases in CFU counts of high touch surfaces in OR 87% (p < 0.001) and patient rooms 76% (p < 0.001). Four rooms presented serine carbapenemases blaKPC, and metallo beta-lactamases blaNDM, blaVIM, blaIMP. confirmed by PCR and sequencing. The in-vitro testing with endemic strains found that after five minutes of pulsed xenon ultraviolet exposure an 8-log reduction was achieved in all cases.

Conclusion

This study is one of the first of its kind in an Ecuador Hospital. We found that pulsed-xenon ultraviolet disinfection technology is an efficacious complement to the established manual cleaning protocols and guidelines in the significant reduction of MDRO.

Best practices for disinfection of noncritical environmental surfaces and equipment in health care facilities: A bundle approach

Over the past decade, there is excellent evidence in the scientific literature that contaminated environmental surfaces and noncritical patient care items play an important role in the transmission of several key health care-associated pathogens including methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci, Acinetobacter, norovirus, and Clostridium difficile. Thus, surface disinfection of noncritical environmental surfaces and medical devices is one of the infection prevention strategies to prevent pathogen transmission. This article will discuss a bundle approach to facilitate effective surface cleaning and disinfection in health care facilities. A bundle is a set of evidence-based practices, generally 3-5, that when performed collectively and reliably have been proven to improve patient outcomes. This bundle has 5 components and the science associated with each component will be addressed. These components are: creating evidence-based policies and procedures; selection of appropriate cleaning and disinfecting products; educating staff to include environmental services, patient equipment, and nursing; monitoring compliance (eg, thoroughness of cleaning, product use) with feedback (ie, just in time coaching); and implementing a "no touch" room decontamination technology and to ensure compliance for patients on contact and enteric precautions. This article will also discuss new technologies (eg, continuous room decontamination technology) that may enhance our infection prevention strategies in the future.

A trial of pulsed xenon ultraviolet disinfection to reduce Clostridioides difficile infection

BACKGROUND

An intervention was designed to test whether the addition of an ultraviolet (UV) disinfection step after terminal cleaning would be helpful in reducing Clostridium difficile infection (CDI) rates in a real-world situation.

METHODS

This study was a quasi-experimental design using 3 units as intervention units for the intervention and 3 similar units as control units. Intervention units 2 hematology and bone marrow transplant units and one medical-surgical unit at a large teaching hospital in the Midwest. UV disinfection was added after patient discharge and terminal cleaning in the intervention units.

RESULTS

At baseline, CDI rates in the intervention and control arms were similar. During the 6 months of UV disinfection, the CDI rate in the intervention units decreased to 11.2 per 10,000 patient days, compared with 28.7 per 10,000 patient days in the control units (P = .03). In addition, the intervention units also saw a reduction in vancomycin-resistant enterococci acquisition.

CONCLUSIONS

The addition of UV disinfection to the terminal cleaning resulted in a reduction in CDI that has been sustained over several months 2 years.

Clinical, operational, and financial impact of an ultraviolet-C terminal disinfection intervention at a community hospital

BACKGROUND

Hospital-acquired infections (HAIs) are a significant contributor to adverse patient outcomes and excess cost of inpatient care. Adjunct ultraviolet-C (UV-C) disinfection may be a viable strategy for reducing HAIs. This study aimed to measure the clinical, operational, and financial impact of a UV-C terminal disinfection intervention in a community hospital setting.

METHODS

Using a pre-post study design, we compared the HAI rates of 5 multidrug-resistant bacteria (Acinetobacter baumannii, Klebsiella pneumoniae, methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus, and Pseudomonas aeruginosa) from 6 culture sites before and after a 12-month facility-wide UV-C intervention. To measure impact of UV-C disinfection on hospital operations, mean inpatient emergency room wait time was calculated. Finally, we conducted a cost saving analysis to evaluate the financial benefits of the intervention.

RESULTS

Overall, 245 HAIs among 13,177 inpatients were observed during a 12-month intervention period, with an incidence rate of 3.94 per 1,000 patient days. This observed HAIs incidence was 19.2% lower than the preintervention period (4.87 vs 3.94 per 1,000 patient days; P = .006). The intervention did not adversely impact emergency department admissions (297.9 vs 296.2 minutes; P = .18) and generated a direct cost savings of $1,219,878 over a 12-month period.

CONCLUSIONS

The UV-C disinfection intervention was associated with a statistically significant facility-wide reduction of multidrug-resistant HAIs and generated substantial direct cost savings without adversely impacting hospital operations.

Effectiveness of ultraviolet disinfection in reducing hospital-acquired Clostridium difficile and vancomycin-resistant Enterococcus on a bone marrow transplant unit

OBJECTIVE

To determine the effectiveness of ultraviolet (UV) environmental disinfection system on rates of hospital-acquired vancomycin-resistant enterococcus (VRE) and Clostridium difficile.

DESIGN

Using active surveillance and an interrupted time-series design, hospital-acquired acquisition of VRE and C. difficile on a bone marrow transplant (BMT) unit were examined before and after implementation of terminal disinfection with UV on all rooms regardless of isolation status of patients. The main outcomes were hospital-based acquisition measured through (1) active surveillance: admission, weekly, and discharge screening for VRE and toxigenic C. difficile (TCD) and (2) clinical surveillance: incidence of VRE and CDI on the unit.

SETTING

Bone marrow transplant unit at a tertiary-care cancer center.ParticipantsStem cell transplant (SCT) recipients.InterventionTerminal disinfection of all rooms with UV regardless of isolation status of patients.

RESULTS

During the 20-month study period, 579 patients had 704 admissions to the BMT unit, and 2,160 surveillance tests were performed. No change in level or trend in the incidence of VRE (trend incidence rate ratio [IRR], 0.96; 95% confidence interval [CI], 0.81-1.14; level IRR, 1.34; 95% CI, 0.37-1.18) or C. difficile (trend IRR, 1.08; 95% CI, 0.89-1.31; level IRR, 0.51; 95% CI, 0.13-2.11) was observed after the intervention.

CONCLUSIONS

Utilization of UV disinfection to supplement routine terminal cleaning of rooms was not effective in reducing hospital-acquired VRE and C. difficile among SCT recipients.

Modelling of ultraviolet light inactivation kinetics of methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus, Clostridium difficile spores and murine norovirus on fomite surfaces

AIMS

Quantitative data on the doses needed to inactivate micro-organisms on fomites are not available for ultraviolet applications. The goal of this study was to determine the doses of UV light needed to reduce bacteria and murine norovirus (MNV) on hard surface fomites through experimentation and to identify appropriate models for predicting targeted levels of reduction.

METHODS AND RESULTS

Stainless steel and Formica laminate coupons were selected as they are common surfaces found in healthcare settings. Test organisms included methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus (VRE), Clostridium difficile and MNV. The fomites were inoculated with 10⁵ -10⁷ bacteria or virus and exposed to a range of UV doses. The order of resistance to UV irradiation was virus, bacterial spore and vegetative cell. The best fitting inactivation curves suggested nonlinear responses to increasing doses after a 3-4 log reduction in the test organisms. The average UV doses required for a 3 log reduction in the C. difficile, MRSA and VRE were 16 000, 6164 and 11 228 (mJ-s cm^-2 ) for stainless steel, respectively, and 16 000, 11 727 and 12 441 (mJ-s cm^-2 ) for Formica laminate, respectively.

CONCLUSIONS

Higher UV light doses are required to inactivate bacteria and viruses on hard surfaces than in suspension. Greater doses are needed to inactivate bacterial spores and MNV compared to vegetative bacteria.

SIGNIFICANCE AND IMPACT OF THE STUDY

Quantitative data and models on UV light doses needed to inactivate bacteria and MNV on hard surfaces are now available. The generalizable results of this study can be used to estimate required UV dosages to achieve targeted levels of inactivation based on estimated levels of contamination or to support quantitative microbial risk assessments.

[Beyond antibiotic therapy - Future antiinfective strategies - Update 2017]

BACKGROUND

The key elements in the therapy of surgical site infections (SSI) are surgical debridement and local and systemic antibiotic therapy; however, due to increasing antibiotic resistance, the development of additional therapeutic measures is of great interest for future trauma and orthopedic surgery.

METHOD

Against the background of our own experimental and clinical experiences and on the basis of the current literature, possible future anti-infective strategies were elaborated.

RESULTS/CONCLUSIONS

Bacteriophages were discovered and clinically implemented approximately one century ago and have been used in Western Europe for about one decade. They are currently used mainly in patients with burn injuries. It is likely that bacteriophages will become of great importance in view of the increasing antibiotic multi-drug resistance; however, they will probably not entirely replace antibiotic drugs. A combined use of bacteriophages and antibiotics is likely to be a more reasonable efficient therapy. In addition, the clinical importance of antimicrobial peptides (AMP) also increases. Up to now the possible use of AMPs is still experimental; however, individual AMPs are already established in the routine therapy (e. g. colistin). Further diagnostic and therapeutic measures may include photodynamic therapy, ultraviolet (UV) light application and differentiated genome analysis as well as the individual metabolism situation (metabolomics) of the pathogen cell and the patient tissue.

Primary Prevention of Clostridium difficile-Associated Diarrhea: Current Controversies and Future Tools

PURPOSE OF REVIEW

Clostridium difficile infection (CDI) is a major cause of morbidity and mortality in hospitalized patients and rates in most places have not decreased significantly despite broad efforts by both hospitals and public health entities. This review aims to provide readers with a better understanding of the limitations of current prevention strategies. We also review potential future tools that may be available for the primary prevention of CDI in the next decade.

RECENT FINDINGS

Research over the last decade has expanded our appreciation of the role of asymptomatic shedding in the healthcare setting and in the community. This review demonstrates that poor quality data underlies even well-established guidance from national authorities on basic topics such as contact precautions, avoidance of alcohol-based hand hygiene products, CDI testing, supplemental cleaning modalities, and the use of bleach solutions. Additionally, we review research on novel preventative interventions such as identification of asymptomatic carriers, supplemental environmental cleaning technologies, vaccines, and the manipulation of the intestinal microbiome. While there is preliminary data that supports further research in all of these areas, the research is not yet robust enough on which to base local or national policy recommendations, though late-phase human clinical trials of CDI vaccine trials are ongoing. Over the last decade, researchers have begun to reassess the traditional infection prevention model for CDI. Data suggesting a greater role for asymptomatic shedders has increased our understanding of current vertical prevention techniques and is forcing researchers to look more at new processes and technologies to decrease disease incidence.

Clinical Practice Guidelines for Clostridium difficile Infection in Adults and Children: 2017 Update by the Infectious Diseases Society of America (IDSA) and Society for Healthcare Epidemiology of America (SHEA)

A panel of experts was convened by the Infectious Diseases Society of America (IDSA) and Society for Healthcare Epidemiology of America (SHEA) to update the 2010 clinical practice guideline on Clostridium difficile infection (CDI) in adults. The update, which has incorporated recommendations for children (following the adult recommendations for epidemiology, diagnosis, and treatment), includes significant changes in the management of this infection and reflects the evolving controversy over best methods for diagnosis. Clostridium difficile remains the most important cause of healthcare-associated diarrhea and has become the most commonly identified cause of healthcare-associated infection in adults in the United States. Moreover, C. difficile has established itself as an important community pathogen. Although the prevalence of the epidemic and virulent ribotype 027 strain has declined markedly along with overall CDI rates in parts of Europe, it remains one of the most commonly identified strains in the United States where it causes a sizable minority of CDIs, especially healthcare-associated CDIs. This guideline updates recommendations regarding epidemiology, diagnosis, treatment, infection prevention, and environmental management.

Impact of pulsed xenon ultraviolet disinfection on surface contamination in a hospital facility's expressed human milk feed preparation area

BACKGROUND

Expressed human milk (EHM) feed preparation areas represent a potential source of unintentional nosocomial infection. Daily disinfection of environmental surfaces remains an essential intervention to mitigate nosocomial infections. The inefficiency of conventional cleaning and disinfection contributes to an increased risk for the acquisition of multi-drug resistant pathogens. "Non touch" technologies such as the pulsed xenon ultraviolet (PX-UVD) light device have documented sustained reduction in surface bacterial colonization and reduced cross contamination.

METHODS

The impact of a PX-UVD on surface colony forming units per square centimeter (cfu/cm²) in feed preparation areas was evaluated following its implementation as standard care. A quasi-experimental study was performed documenting bacterial colonization from 6 high risk feed preparation areas in a community care hospital in South Africa. Pre and post conventional cleaning neutralizing rinse swabs were collected fortnightly over a 16 week control period prior to the introduction of the PX-UVD and compared to a matching set of samples for the PX-UVD period.

RESULTS

A 90% reduction in total surface bioburden was noted from the control period (544 cfu/cm²) compared to the corresponding PX-UVD period (50 cfu/cm²). Sub -analysis of both the Pre-clean Control: Pre-clean PX-UVD counts as well as the Post-clean Control: Post-clean PX-UVD counts noted significant improvements (p < 0.001). A statistically significant improvement was noted between pre-and post-cleaning total surface bioburden following exposure to the PX-UVD (p = 0.0004). The introduction of the PX-UVD was associated with a sustained reduction in the pre clean bioburden counts with a risk trend (per week) 0.19, (95% CI [0.056, 0.67], p = 0.01).

DISCUSSION

The use of a PX-UVD as adjunct to standard cleaning protocols was associated with a significant decrease in surface bioburden. The study demonstrated the inefficiency of conventional cleaning. Persistence of potentially pathological species in both periods highlights current health sector challenges.

Clostridium Difficile Infection in Acute Care Hospitals: Systematic Review and Best Practices for Prevention

OBJECTIVE Prevention of Clostridium difficile infection (CDI) in acute-care hospitals is a priority for hospitals and clinicians. We performed a qualitative systematic review to update the evidence on interventions to prevent CDI published since 2009. DESIGN We searched Ovid, MEDLINE, EMBASE, The Cochrane Library, CINAHL, the ISI Web of Knowledge, and grey literature databases from January 1, 2009 to August 1, 2015. SETTING We included studies performed in acute-care hospitals. PATIENTS OR PARTICIPANTS We included studies conducted on hospitalized patients that investigated the impact of specific interventions on CDI rates. INTERVENTIONS We used the QI-Minimum Quality Criteria Set (QI-MQCS) to assess the quality of included studies. Interventions were grouped thematically: environmental disinfection, antimicrobial stewardship, hand hygiene, chlorhexidine bathing, probiotics, bundled approaches, and others. A meta-analysis was performed when possible. RESULTS Of 3,236 articles screened, 261 met the criteria for full-text review and 46 studies were ultimately included. The average quality rating was 82% according to the QI-MQCS. The most effective interventions, resulting in a 45% to 85% reduction in CDI, included daily to twice daily disinfection of high-touch surfaces (including bed rails) and terminal cleaning of patient rooms with chlorine-based products. Bundled interventions and antimicrobial stewardship showed promise for reducing CDI rates. Chlorhexidine bathing and intensified hand-hygiene practices were not effective for reducing CDI rates. CONCLUSIONS Daily and terminal cleaning of patient rooms using chlorine-based products were most effective in reducing CDI rates in hospitals. Further studies are needed to identify the components of bundled interventions that reduce CDI rates. Infect Control Hosp Epidemiol 2017;38:476-482.

Deployment of a touchless ultraviolet light robot for terminal room disinfection: The importance of audit and feedback

Touchless ultraviolet disinfection (UVD) devices effectively reduce the bioburden of epidemiologically relevant pathogens, including Clostridium difficile. During a 25-month implementation period, UVD devices were deployed facilitywide for the terminal disinfection of rooms that housed a patient who tested positive for C difficile. The deployment was performed with structured education, audit and feedback, and resulted in a multidisciplinary practice change that maximized the UVD capture rate from 20% to 100%.

'No touch' technologies for environmental decontamination: focus on ultraviolet devices and hydrogen peroxide systems

PURPOSE OF REVIEW

This article reviews 'no touch' methods for disinfection of the contaminated surface environment of hospitalized patients' rooms. The focus is on studies that assessed the effectiveness of ultraviolet (UV) light devices, hydrogen peroxide systems, and self-disinfecting surfaces to reduce healthcare-associated infections (HAIs).

RECENT FINDINGS

The contaminated surface environment in hospitals plays an important role in the transmission of several key nosocomial pathogens including methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus spp., Clostridium difficile, Acinetobacter spp., and norovirus. Multiple clinical trials have now demonstrated the effectiveness of UV light devices and hydrogen peroxide systems to reduce HAIs. A limited number of studies have suggested that 'self-disinfecting' surfaces may also decrease HAIs.

SUMMARY

Many studies have demonstrated that terminal cleaning and disinfection with germicides is often inadequate and leaves environmental surfaces contaminated with important nosocomial pathogens. 'No touch' methods of room decontamination (i.e., UV devices and hydrogen peroxide systems) have been demonstrated to reduce key nosocomial pathogens on inoculated test surfaces and on environmental surfaces in actual patient rooms. Further UV devices and hydrogen peroxide systems have been demonstrated to reduce HAI. A validated 'no touch' device or system should be used for terminal room disinfection following discharge of patients on contact precautions. The use of a 'self-disinfecting' surface to reduce HAI has not been convincingly demonstrated.

No-Touch Disinfection Methods to Decrease Multidrug-Resistant Organism Infections: A Systematic Review and Meta-analysis

BACKGROUND Recent studies have shown that using no-touch disinfection technologies (ie, ultraviolet light [UVL] or hydrogen peroxide vapor [HPV] systems) can limit the transmission of nosocomial pathogens and prevent healthcare-associated infections (HAIs). To investigate these findings further, we performed a systematic literature review and meta-analysis on the impact of no-touch disinfection methods to decrease HAIs. METHODS We searched PubMed, CINAHL, CDSR, DARE and EMBASE through April 2017 for studies evaluating no-touch disinfection technology and the nosocomial infection rates for Clostridium difficile, methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE), and other multidrug-resistant organisms (MDROs). We employed random-effect models to obtain pooled risk ratio (pRR) estimates. Heterogeneity was evaluated with I2 estimation and the Cochran Q statistic. Pooled risk ratios for C. difficile, MRSA, VRE, and MDRO were assessed separately. RESULTS In total, 20 studies were included in the final review: 13 studies using UVL systems and 7 studies using HPV systems. When the results of the UVL studies were pooled, statistically significant reduction ins C. difficile infection (CDI) (pRR, 0.64; 95% confidence interval [CI], 0.49-0.84) and VRE infection rates (pRR, 0.42; 95% CI, 0.28-0.65) were observed. No differences were found in rates of MRSA or gram-negative multidrug-resistant pathogens. CONCLUSIONS Ultraviolet light no-touch disinfection technology may be effective in preventing CDI and VRE infection. Infect Control Hosp Epidemiol 2018;39:20-31.

Comparison of two whole-room ultraviolet irradiation systems for enhanced disinfection of contaminated hospital patient rooms

BACKGROUND

Ultraviolet (UV) light decontamination systems are being used increasingly to supplement terminal disinfection of patient rooms. However, efficacy may not be consistent in the presence of soil, especially against Clostridium difficile spores.

AIM

To demonstrate in-use efficacy of two whole-room UV decontamination systems against three hospital pathogens with and without soil.

METHODS

For each system, six patient rooms were decontaminated with UV irradiation (enhanced disinfection) following manual terminal cleaning. Total aerobic colony counts of surface contamination were determined by spot-sampling 15 environmental sites before and after terminal disinfection and after UV irradiation. Efficacy against biological indicator coupons (stainless-steel discs) was performed for each system using test bacteria (10⁶ cfu EMRSA-15 variant A, carbapenemase-producing Klebsiella pneumoniae) or spores (10⁵ cfu C. difficile 027), incorporating low soiling [0.03% bovine serum albumin (BSA)], heavy soiling (10% BSA) or synthetic faeces (C. difficile only) placed at five locations in the room.

FINDINGS

UV disinfection eliminated contamination after terminal cleaning in 8/14 (57%) and 11/14 (79%) sites. Both systems demonstrated 4-5 log₁₀ reductions in meticillin-resistant Staphylococcus aureus and K. pneumoniae at low soiling. Lower and more variable log₁₀ reductions were achieved when heavy soiling was present. Between 0.1 and 4.8 log₁₀ reductions in C. difficile spores were achieved with low but not heavy soil challenge.

CONCLUSION

Terminal disinfection should be performed on all surfaces prior to UV decontamination. In-house validation studies should be considered to ensure optimal positioning in each room layout and sufficient cycle duration to eliminate target pathogens.