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

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.

Using photon disinfection technologies for reducing bioburden in hospitals

BACKGROUND

Environmental cleaning and disinfection is the basis of the prevention of healthcare-acquired infections (HAIs).

AIM

This study aimed to describe photon disinfection technologies (PDTs), report their impact on inactivating micro-organisms and preventing HAIs and to create recommendations for their implementation in hospital settings.

METHODS

An integrated literature review was completed to evaluate and report the impact of PDTs in hospital settings. The quality of 23 articles were assessed, their contents analysed and results reported according to the PICOT model.

FINDINGS

The microbiological impact of the PDT varied by micro-organism, settings and according to the used devices. It was crucial that environmental cleaning was completed before the disinfection.

CONCLUSION

The implementation of PDT in the hospital setting requires inquiry from the viewpoints of microbiological, environmental, occupational, technical and human safety. To enhance the safe implementation of PDTs, the construction and use of evidence-based global standards for PDT are crucial.

Minimizing the risk of Clostridioides difficile infection as an early complication of autologous stem cell transplantation

This quality improvement project aimed to reduce institutional incidence of Clostridioides difficile infection (CDI) following autologous stem cell transplantation. CDI incidence per transplant was .17 in a baseline period and .09 following the implementation of postdischarge ultraviolet room cleaning (χ2 = 2.11, p = .15).

Effectiveness of Ultraviolet-C Disinfection on Hospital-Onset Gram-Negative Rod Bloodstream Infection: A Nationwide Stepped-Wedge Time-Series Analysis

BACKGROUND

The effectiveness of enhanced terminal room cleaning with ultraviolet C (UV-C) disinfection in reducing gram-negative rod (GNR) infections has not been well evaluated. We assessed the association of implementation of UV-C disinfection systems with incidence rates of hospital-onset (HO) GNR bloodstream infection (BSI).

METHODS

We obtained information regarding UV-C use and the timing of implementation through a survey of all Veterans Health Administration (VHA) hospitals providing inpatient acute care. Episodes of HO-GNR BSI were identified between January 2010 and December 2018. Bed days of care (BDOC) was used as the denominator. Over-dispersed Poisson regression models were fitted with hospital-specific random intercept, UV-C disinfection use for each month, baseline trend, and seasonality as explanatory variables. Hospitals without UV-C use were also included to the analysis as a nonequivalent concurrent control group.

RESULTS

Among 128 VHA hospitals, 120 provided complete survey responses with 40 reporting implementations of UV-C systems. We identified 13 383 episodes of HO-GNR BSI and 24 141 378 BDOC. UV-C use was associated with a lower incidence rate of HO-GNR BSI (incidence rate ratio: 0.813; 95% confidence interval: .656-.969; P = .009). There was wide variability in the effect size of UV-C disinfection use among hospitals.

CONCLUSIONS

In this large quasi-experimental analysis within the VHA System, enhanced terminal room cleaning with UV-C disinfection was associated with an approximately 19% lower incidence of HO-GNR BSI, with wide variability in effectiveness among hospitals. Further studies are needed to identify the optimal implementation strategy to maximize the effectiveness of UV-C disinfection technology.

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.

Hospital surface disinfection using ultraviolet germicidal irradiation technology: A review

Ultraviolet germicidal irradiation (UVGI) technologies have emerged as a promising alternative to biocides as a means of surface disinfection in hospitals and other healthcare settings. This paper reviews the methods used by researchers and clinicians in deploying and evaluating the efficacy of UVGI technology. The type of UVGI technology used, the clinical setting where the device was deployed, and the methods of environmental testing that the researchers followed are investigated. The findings suggest that clinical UVGI deployments have been growing steadily since 2010 and have increased dramatically since the start of the COVID-19 pandemic. Hardware platforms and operating procedures vary considerably between studies. Most studies measure efficacy of the technology based on the objective measurement of bacterial bioburden reduction; however, studies conducted over longer durations have examined the impact of UVGI on the reduction of healthcare associated infections (HCAIs). Future trends include increased automation and the use of UVGI technologies that are safer for use around people. Although existing evidence seems to support the efficacy of UVGI as a tool capable of reducing HCAIs, more research is needed to measure the magnitude of these effects and to establish recommended best practices.

Impact of environmental hygiene interventions on healthcare-associated infections and patient colonization: a systematic review

BACKGROUND

Healthcare-associated infections (HAI) are one of the gravest threats to patient safety worldwide. The importance of the hospital environment has recently been revalued in infection prevention and control. Though the literature is evolving rapidly, many institutions still do not consider healthcare environmental hygiene (HEH) very important for patient safety. The evidence for interventions in the healthcare environment on patient colonization and HAI with multidrug-resistant microorganisms (MDROs) or other epidemiologically relevant pathogens was reviewed.

METHODS

We performed a systematic review according to the PRISMA guidelines using the PubMed and Web of Science databases. All original studies were eligible if published before December 31, 2019, and if the effect of an HEH intervention on HAI or patient colonization was measured. Studies were not eligible if they were conducted in vitro, did not include patient colonization or HAI as an outcome, were bundled with hand hygiene interventions, included a complete structural rebuild of the healthcare facility or were implemented during an outbreak. The primary outcome was the comparison of the intervention on patient colonization or HAI compared to baseline or control. Interventions were categorized by mechanical, chemical, human factors, or bundles. Study quality was assessed using a specifically-designed tool that considered study design, sample size, control, confounders, and issues with reporting. The effect of HEH interventions on environmental bioburden was studied as a secondary outcome.

FINDINGS

After deduplication, 952 records were scrutinized, of which 44 were included for full text assessment. A total of 26 articles were included in the review and analyzed. Most studies demonstrated a reduction of patient colonization or HAI, and all that analyzed bioburden demonstrated a reduction following the HEH intervention. Studies tested mechanical interventions (n = 8), chemical interventions (n = 7), human factors interventions (n = 3), and bundled interventions (n = 8). The majority of studies (21/26, 81%) analyzed either S. aureus, C. difficile, and/or vancomycin-resistant enterococci. Most studies (23/26, 88%) reported a decrease of MDRO-colonization or HAI for at least one of the tested organisms, while 58% reported a significant decrease of MDRO-colonization or HAI for all tested microorganisms. Forty-two percent were of good quality according to the scoring system. The majority (21/26, 81%) of study interventions were recommended for application by the authors. Studies were often not powered adequately to measure statistically significant reductions.

INTERPRETATION

Improving HEH helps keep patients safe. Most studies demonstrated that interventions in the hospital environment were related with lower HAI and/or patient colonization. Most of the studies were not of high quality; additional adequately-powered, high-quality studies are needed. Systematic registration number: CRD42020204909.

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.

Impact of no-touch ultraviolet light room disinfection systems on Clostridioides difficile infections

Ultraviolet light (UVL) room disinfection has emerged as an adjunct to manual cleaning of patient rooms. Two different no-touch UVL devices were implemented in 3 health system hospitals to reduce Clostridioides difficile infections (CDI). CDI rates at all 3 facilities remained unchanged following implementation of UVL disinfection. Preintervention CDI rates were generally low, and data from one hospital showed high compliance with manual cleaning, which may have limited the impact of UVL disinfection.

Feasibility of ultraviolet light-emitting diode irradiation robot for terminal decontamination of coronavirus disease 2019 (COVID-19) patient rooms

OBJECTIVE

To investigate the feasibility of using an ultraviolet light-emitting diode (UV LED) robot for the terminal decontamination of coronavirus disease 2019 (COVID-19) patient rooms.

METHODS

We assessed the presence of viral RNA in samples from environmental surfaces before and after UV LED irradiation in COVID-19 patient rooms after patient discharge.

RESULTS

We analyzed 216 environmental samples from 17 rooms: 2 from airborne infection isolation rooms (AIIRs) in the intensive care unit (ICU) and 15 from isolation rooms in the community treatment center (CTC). Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA was detected in 40 (18.5%) of 216 samples after patient discharge: 12 (33.3%) of 36 samples from AIIRs in the ICU, and 28 (15.6%) of 180 samples from isolation rooms in the CTC. In 1 AIIR, all samples were PCR negative after UV LED irradiation. In the CTC rooms, 14 (8.6%) of the 163 samples were PCR positive after UV LED irradiation. However, viable virus was not recovered from the culture of any of the PCR-positive samples.

CONCLUSIONS

Although no viable virus was recovered, SARS-CoV-2 RNA was detected on various environmental surfaces. The use of a UV LED disinfection robot was effective in spacious areas such as an ICU, but its effects varied in small spaces like CTC rooms. These findings suggest that the UV LED robot may need enough space to disinfect rooms without recontamination by machine wheels or insufficient disinfection by shadowing.

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.

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.

Investigation of the effects of an ultraviolet germicidal irradiation system on concentrations of aerosolized surrogates for common veterinary pathogens

OBJECTIVE

To determine whether exposure to UV germicidal irradiation (UVGI) reduces concentrations of viable aerosolized microorganisms (attenuated strains of common veterinary pathogens) in a simulated heating, ventilation, and air conditioning (HVAC) system.

SAMPLE

42 air samples seeded with bacteriophage MS2 or attenuated strains of Bordetella bronchiseptica, feline calicivirus, feline herpesvirus-1, canine parvovirus, or canine distemper virus (6/microorganism) or with no microorganisms added (6).

PROCEDURES

A simulated HVAC unit was built that included a nebulizer to aerosolize microorganisms suspended in phosphate-buffered water, a fan to produce airflow, 2 UVGI bulb systems, and an impinger for air sampling. Ten-minute trials (3 with UVGI, 3 without UVGI, and 1 negative control) were conducted for each microorganism. Impingers collected microorganisms into phosphate-buffered water for subsequent quantification with culture-based assays. Results for samples yielding no target microorganisms were recorded as the assay's lower limit of detection. Statistical analysis was not performed.

RESULTS

The UVGI treatment resulted in subjectively lower concentrations of viable MS2, B bronchiseptica, and canine distemper virus (arithmetic mean ± SD log₁₀ microorganism reduction, 2.57 ± 0.47, ≥ 3.45 ± 0.24, and ≥ 1.50 ± 0.25, respectively) collected from air. Feline herpesvirus-1 was detected in only 1 sample without and no samples with UVGI treatment. Feline calicivirus and canine parvovirus were not detectable in any collected samples.

CONCLUSIONS AND CLINICAL RELEVANCE

Results for some surrogates of veterinary pathogens suggested a potential benefit to supplementing manual disinfection practices with UVGI-based air cleaning systems in animal care environments. Further research is needed to investigate the utility of UVGI in operating HVAC systems.

Clostridioides difficile-Associated Diarrhea: Infection Prevention Unknowns and Evolving Risk Reduction Strategies

PURPOSE OF REVIEW

New controversies in the diagnosis and prevention of Clostridiodes difficile are challenging and at times changing infection control practice at many medical centers.

RECENT FINDINGS

Molecular epidemiologic studies are changing our understanding of C. difficile and its spectrum of disease. C. difficile as a hospital-acquired infection is likely largely overdiagnosed given overly sensitive molecular testing and widespread colonization of ill or debilitated patients. Clostridiodes difficile infection continues to challenge infection prevention programs. Shifts in our understanding of the epidemiology of this organism and its spectrum of clinical presentations are changing the approach to prevention efforts. Nevertheless, cleanliness of the healthcare environment and antimicrobial stewardship remain core risk reduction strategies. Other strategies such as screening and isolation are inciting controversy. The optimal infection prevention strategies for C. difficile remain the subject of intense study and debate.