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

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.

Effectiveness of ultraviolet-C disinfection systems for reduction of multi-drug resistant organism infections in healthcare settings: A systematic review and meta-analysis

This study aimed to summarise the findings of the studies assessing the effectiveness of ultraviolet C (UV-C) room disinfection in reducing the incidence rate of healthcare-associated multi-drug-resistant organism (MDRO) infections. A systematic screening was conducted using PubMed, EMBASE, and Scopus for randomised controlled trials (RCTs), quasi-experimental studies, and before-after studies, which assessed the efficacy of the UV-C disinfectant system in reducing the incidence of MDRO infections. A random-effects model was used for the analysis. Effect sizes were described as incidence rate ratio (IRR) with 95% confidence intervals (CI). Nine studies were included, all of which were conducted in the USA. No statistically significant reduction in Clostridioides difficile (CD) (IRR: 0.90, 95% CI; 0.62-1.32) and vancomycin-resistant enterococcal (VRE) infection rates (IRR 0.72, 95% CI; 0.38-1.37) was observed with the use of UV-C, but the risk of Gram-negative rod infection was reduced (IRR 0.82, 95% CI; 0.68-0.99).

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.

Rapid disinfection of radiology treatment rooms using an autonomous ultraviolet germicidal irradiation robot

BACKGROUND

Ultraviolet germicidal irradiation (UVGI) technologies have emerged as a promising adjunct to manual cleaning, however, their potential to shorten cleaning times remains unexplored.

METHODS

A <10-minute disinfection procedure was developed using a robotic UVGI platform. The efficacy and time to perform the UVGI procedure in a CT scan treatment room was compared with current protocols involving manual disinfection using biocides. For each intervention, environmental samples were taken at 12 locations in the room before and after disinfection on seven distinct occasions.

RESULTS

The mean UVC dose at each sample location was found to be 13.01 ± 4.36 mJ/cm², which exceeded published UVC thresholds for achieving log reductions of many common pathogens. Significant reductions in microbial burden were measured after both UVGI (P≤.001) and manual cleaning (P≤.05) conditions, with the UVGI procedure revealing the largest effect size (r = 0.603).

DISCUSSION

These results support the hypothesis that automated deployments of UVGI technology can lead to germicidal performance that is comparable with, and potentially better than, current manual cleaning practices.

CONCLUSIONS

Our findings provide early evidence that the incorporation of automated UVGI procedures into cleaning workflow could reduce turnaround times in radiology, and potentially other hospital settings.

Occupant-centric robotic air filtration and planning for classrooms for Safer school reopening amid respiratory pandemics

Coexisting with the current COVID-19 pandemic is a global reality that comes with unique challenges impacting daily interactions, business, and facility maintenance. A monumental challenge accompanied is continuous and effective disinfection of shared spaces, such as office/school buildings, elevators, classrooms, and cafeterias. Although ultraviolet light and chemical sprays are routines for indoor disinfection, they irritate humans, hence can only be used when the facility is unoccupied. Stationary air filtration systems, while being irritation-free and commonly available, fail to protect all occupants due to limitations in air circulation and diffusion. Hence, we present a novel collaborative robot (cobot) disinfection system equipped with a Bernoulli Air Filtration Module, with a design that minimizes disturbance to the surrounding airflow and maneuverability among occupants for maximum coverage. The influence of robotic air filtration on dosage at neighbors of a coughing source is analyzed with derivations from a Computational Fluid Dynamics (CFD) simulation. Based on the analysis, the novel occupant-centric online rerouting algorithm decides the path of the robot. The rerouting ensures effective air filtration that minimizes the risk of occupants under their detected layout. The proposed system was tested on a 2 × 3 seating grid (empty seats allowed) in a classroom, and the worst-case dosage for all occupants was chosen as the metric. The system reduced the worst-case dosage among all occupants by 26% and 19% compared to a stationary air filtration system with the same flow rate, and a robotic air filtration system that traverses all the seats but without occupant-centric planning of its path, respectively. Hence, we validated the effectiveness of the proposed robotic air filtration system.

Statistical Design of Overnight Trials for the Evaluation of the Number of Operating Rooms That Can Be Disinfected by an Ultraviolet Light Disinfection Robotic System

Background and objective

The number of ultraviolet light disinfection robot systems that are needed for a facility’s surgical suite(s) and/or procedure suite(s) depends in part on how many rooms need to be disinfected overnight by each robot and how long this will take. The answer needs to be determined separately for each surgical and procedure suite because those variables vary both among facilities and among operating rooms or procedure rooms within facilities. In this study, we consider statistical designs to assess how many rooms a facility can reliably (≥90% chance) disinfect overnight using an ultraviolet light disinfection robot system.

Methods

We used 133,927 observed disinfection times from 700 rooms as a population from which repeated samples were drawn with replacement in Monte-Carlo simulations. We used eight-hour and 10-hour shift lengths being multiples of 40 hours for full-time hourly employees.

Results

One possible strategy that we examined was to estimate total disinfection times by estimating the mean for each room and then summing up the means. However, that did not correctly answer the question of how many rooms can reliably be available for the next day’s first case. Summing up a percentile (e.g., 90%) instead also was inaccurate, because the proper percentile depended on the number of rooms.

A suitable strategy is a brief trial (e.g., nine nights or 19 nights) with the endpoint being the daily number of rooms disinfected. Empirically, the smallest count of rooms disinfected among nine nights or the second smallest count among 19 nights are 10^th percentiles (i.e., ≈90% probability that at least that number of rooms can be disinfected in the future). The drawback is that while this approach gives the probability of a night with fewer rooms disinfected, it does not give information as to how many fewer rooms may either skip ultraviolet decontamination or start late the next workday because disinfection was not completed. Our simulations showed that there is a substantial probability (≥95%) of at most two rooms fewer or one room greater than the 10^th percentile with a nine-night trial and one room fewer or greater with a 19-night trial.

Conclusions

Because probability distributions of disinfection times are heterogeneous both among rooms and among treatments for the same room, each facility should plan to perform its own trial of nine nights or 19 nights. This will provide results that are within two rooms or one room of the correct answer in the long term. This information can be used when planning purchasing decisions, leasing, and technician staffing decisions.

Clostridioides difficile Infection in Children: The Role of Infection Prevention and Antimicrobial Stewardship

There are 2 primary approaches to prevent Clostridioides difficile infection (CDI) in children: prevent transmission and acquisition of the organism and prevent the progression from colonization to disease. The most important interventions to reduce the risk of transmission include contact precautions, hand hygiene, and environmental disinfection. Glove use minimizes contamination of the hands by spores and is associated with reductions in CDI incidence. Hand hygiene with soap and water and disinfection with a sporicidal agent are recommended as the best approaches in hyperendemic settings. Because antibiotic exposure is the most important modifiable risk factor for CDI, antimicrobial stewardship focused on identified high-risk antibiotic classes (including clindamycin, fluoroquinolones, and third- and fourth-generation cephalosporins) is critical to preventing progression from colonization to infection. Despite clear evidence that antimicrobial stewardship programs (ASPs) are associated with reduced CDI rates in adults, data demonstrating the ASP impact on pediatric CDI are lacking.

Rewriting the playbook: infection prevention practices to mitigate nosocomial severe acute respiratory syndrome coronavirus 2 transmission

PURPOSE OF REVIEW

Given the limited evidence and experience with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), this novel pathogen has challenged the field of infection prevention. Despite uncertainty, infection prevention principles and experience with similar diseases have helped guide how to best protect providers and patients against disease acquisition.

RECENT FINDINGS

Guidance to date has relied on data from SARS-CoV-1 and MERS-CoV to guide practices on patient isolation and personal protective equipment (PPE) use. Although a face mask and eye protection are likely adequate for most clinical scenarios, published guidelines for PPE can be confusing and conflicting. Consensus for what constitutes a high-risk aerosol-generating procedure (AGP) is lacking, but most agree providers performing procedures such as bronchoscopy, intubation, and cardiopulmonary resuscitation would likely benefit from the use of an N95 respirator and eye protection.

SUMMARY

Needed research to elucidate the predominant SARS-CoV-2 mode of transmission is not likely to be completed in the immediate future. Recommendations for PPE to mitigate procedure-associated risk remain controversial. Nonetheless, implementation of existing measures based on basic infection prevention principles is likely to prevent transmission significantly.