Analysis of SteraMist ionized hydrogen peroxide technology in the sterilization of N95 respirators and other PPE: a quality improvement study

Factors affecting decontamination of N95 masks for reuse: Feasibility & practicality of various methods

The SARS-CoV-2 pandemic has led to an enormous increase in cases worldwide in a short time. The potential shortage might call for the reuse of personal protective equipment especially N95 masks. In this review, the methods available for decontamination of N95 masks have been compared to highlight the advantages and efficacies of different methods. Studies conducted to evaluate the biocidal efficacy, effect on filtration efficacy of the decontamination method, and maintenance of structural integrity of masks, were reviewed. Ultraviolet germicidal irradiation (UVGI) and hydrogen peroxide (H2O2) vapour were the most commonly evaluated interventions and showed good germicidal activity without significant deleterious effects on mask performance. Vapourous H2O2 was the best method as it maintained NIOSH (The National Institute for Occupational Safety and Health) recommendations of the mask on re-use and additionally, one mask could be decontaminated and reused 30 times. Ethylene oxide (EtO) preserved the maximum filtration efficacy and flow resistance. Chemical and heat-based methods had the advantages of being cost-effective and feasible but affected the structural integrity and fit of the masks. For the decontamination of N95 masks, among the heat-based methods steam was found to be the best for low middle-income countries setting. H2O2-based methods, UVGI, and EtO all exhibited both adequate biocidal efficacies and functionality (fit testing and structural integrity). Further studies on logistics, healthcare worker acceptability of reuse, and actual efficacy of protection against SARS-CoV-2 infection should be carried out to validate the use of decontamination in the real-life settings.

Mask decontamination methods (model N95) for respiratory protection: a rapid review

BACKGROUND

N95 respiratory protection masks are used by healthcare professionals to prevent contamination from infectious microorganisms transmitted by droplets or aerosols.

METHODS

We conducted a rapid review of the literature analyzing the effectiveness of decontamination methods for mask reuse. The database searches were carried out up to September 2020. The systematic review was conducted in a way which simplified the stages of a complete systematic review, due to the worldwide necessity for reliable fast evidences on this matter.

RESULTS

A total of 563 articles were retrieved of which 48 laboratory-based studies were selected. Fifteen decontamination methods were included in the studies. A total of 19 laboratory studies used hydrogen peroxide, 21 studies used ultraviolet germicidal irradiation, 4 studies used ethylene oxide, 11 studies used dry heat, 9 studies used moist heat, 5 studies used ethanol, two studies used isopropanol solution, 11 studies used microwave oven, 10 studies used sodium hypochlorite, 7 studies used autoclave, 3 studies used an electric rice cooker, 1 study used cleaning wipes, 1 study used bar soap, 1 study used water, 1 study used multi-purpose high-level disinfection cabinet, and another 1 study used chlorine dioxide. Five methods that are promising are as follows: hydrogen peroxide vapor, ultraviolet irradiation, dry heat, wet heat/pasteurization, and microwave ovens.

CONCLUSIONS

We have presented the best available evidence on mask decontamination; nevertheless, its applicability is limited due to few studies on the topic and the lack of studies on real environments.

Outdoor disinfectant sprays for the prevention of COVID-19: Are they safe for the environment?

Due to the wide range of viability on inanimate surfaces and fomite transmission of SARS-CoV-2, hydrogen peroxide (0.5%, HP) and hypochlorite-based (0.1%, HC) disinfectants (common biocides) are proposed by World Health Organization to mitigate the spread of this virus in healthcare settings. They can be adopted and applied to outdoor environments. However, many studies have shown that these two disinfectants are toxic to fishes and aquatic non-target organisms (primary producers and macroinvertebrates). The global market of these disinfectants will increase in coming years due to COVID-19. Therefore, it is urgent to highlight the toxicities of these disinfectants. The main findings of this article allow the community to develop a new strategy to protect the environment against the hazardous effects of disinfectants. Therefore, we use the "toxicity calculated ratio (TC ratio)" that refers to the fold increase or decrease in the toxicities reported in the literature (NOEC, LOEC, LC50 and EC50) relative to the WHO-recommended dose of HP and HC. The calculated TC ratios are valuable for policy makers to formulate the regulations to prevent disinfectant exposure in the environment. Our results were collected via PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analysis) guidelines and showed that the TC ratios are from the single digits to several thousand-fold lower than the HP and HC recommended dose, which means these disinfectants are potentially dangerous to non-target organisms. The results also showed that HP and HC are toxic to the growth and reproduction of non-target organisms. Therefore, we recommend policymakers formulate protocols for critical assessment and monitoring of the environment-especially on non-target organisms in water bodies located in and around disinfectant-exposed areas to safeguard the environment in the future.

A Crisis-Responsive Framework for Medical Device Development Applied to the COVID-19 Pandemic

The disruption of conventional manufacturing, supply, and distribution channels during the COVID-19 pandemic caused widespread shortages in personal protective equipment (PPE) and other medical supplies. These shortages catalyzed local efforts to use nontraditional, rapid manufacturing to meet urgent healthcare needs. Here we present a crisis-responsive design framework designed to assist with product development under pandemic conditions. The framework emphasizes stakeholder engagement, comprehensive but efficient needs assessment, rapid manufacturing, and modified product testing to enable accelerated development of healthcare products. We contrast this framework with traditional medical device manufacturing that proceeds at a more deliberate pace, discuss strengths and weakness of pandemic-responsive fabrication, and consider relevant regulatory policies. We highlight the use of the crisis-responsive framework in a case study of face shield design and production for a large US academic hospital. Finally, we make recommendations aimed at improving future resilience to pandemics and healthcare emergencies. These include continued development of open source designs suitable for rapid manufacturing, education of maker communities and hospital administrators about rapidly-manufactured medical devices, and changes in regulatory policy that help strike a balance between quality and innovation.

N95 reprocessing by low temperature sterilization with 59% vaporized hydrogen peroxide during the 2020 COVID-19 pandemic

BACKGROUND

Response to the COVID-19 pandemic by hospital systems has been strained by severe shortages in personal protective equipment (PPE), particularly N95 respirators. Recently, the Centers for Disease Control and Prevention endorsed decontamination strategies to prolong the lifespan of single use respirators. Battelle and Duke University have validated hospital protocols to decontaminate respirators using vaporized hydrogen peroxide (VHP) at 30%-35% concentrations. To prolong our supply of respirators, we evaluated and implemented VHP decontamination at 59% hydrogen peroxide concentration while detailing the effects of this process on the filtration efficiency and quantitative fit of single-use respirators. This study may help other health systems develop local solutions to their N95 mask shortage during this COVID-19 pandemic.

METHODS

N95 respirators (3M 8211 FF and 9210 FF) that were treated with 5 and 10 cycles of VHP by the V-PRO maX Low Temperature Sterilization System were evaluated quantitatively for filtration efficiency as well as with quantitative fit testing per Occupational Safety and Health Administration standards. A decontamination protocol was concurrently implemented at our institution. This process involved depositing used masks, reprocessing, and re-distributing treated masks efficiently back to frontline providers. Furthermore, we implemented patient safety officers on COVID-19/person under investigation units to ensure optimized donning/doffing of respirators through frontline provider education.

RESULTS

There were no statistically significant changes in mean filtration efficiency between the control and VHP-treated respirators. Furthermore, both treated and untreated respirators demonstrated fit factors above the minimum pass requirement.

CONCLUSIONS

We have successfully demonstrated that N95 respirator decontamination with VHP at 59% hydrogen peroxide can be safely utilized to decontaminate single-use N95 respirators without significant effects on filtration efficiency or quantitative fit testing. With the COVID-19 pandemic and N95 respirator shortage, health systems without access to commercial decontamination processes should investigate the viability of such a process in their facilities.

Viricidal treatments for prevention of coronavirus infection

Coronavirus disease 2019 (COVID-19), which causes severe acute respiratory syndrome and lung failure, is caused by the novel coronavirus, also known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Due to high transmission rates from individual to individual, it has progressed to a pandemic. However, indirect transmission from inanimate objects or surfaces that have come in contact with a patient poses an even more significant threat as it is difficult to trace the source of infection in these cases. Therefore, these surfaces and objects require disinfection with chemicals having potent viricidal activity. These include alcohols, aldehydes, quaternary ammonium compounds, chlorhexidine, and chlorine-based disinfectants, among others. They vary in their viricidal activity depending on their structure, concentrations, and mechanism of action. Several studies have looked into these agents and the transmission of the virus related to it. Moreover, certain viricides, if used as constituents of commercially available oral disinfectants, can further aid in preventing ventilator-associated pneumonia and maintain oral hygiene. However, these chemicals are not entirely free of potential hazards. In this review, we have compiled and critically appraised some commonly used viricidal agents in healthcare settings and the role they can play in the prevention of SARS-CoV-2 transmission.

Assessing the quality of nontraditional N95 filtering face-piece respirators available during the COVID-19 pandemic

BACKGROUND

During the current COVID-19 pandemic, supply chains for Personal Protective Equipment (PPE) have been severely disrupted and many products, particularly surgical N95 filtering facepiece respirators (FFRs; "masks") are in short supply. As a consequence, an Emergency Use Authorization (EUA) from the FDA has allowed importation of N95-type masks manufactured to international standards; these include KN95 masks from China and FFP2 masks from the European Union.

METHODS

We conducted a survey of mask in the inventory of major academic medical centers in Boston, MA to determine provenance and manufacturer. We then assembled a simple apparatus for performing a necessary (but not sufficient) test of filtration performance and tested masks from the inventory; an accompanying website shows how to build and use the testing apparatus.

RESULTS

Our survey showed that, seven months after the start of the COVID-19 pandemic, over 100 different makes and models of N95-type masks are in the inventory of local hospitals as opposed to 2-5 models under normal circumstances. A substantial number of unfamiliar masks are from unknown manufacturers. Many did not perform to accepted standards and are likely to be counterfeit. Due to the absence of publicly available information on mask suppliers in the FDA EUA and confusing or inconsistent labeling of KN95 masks, it is difficult to distinguish legitimate and counterfeit products.

CONCLUSIONS

Many of the FFR masks available for procurement during the COVID-19 pandemic do not provide levels of fit and filtration similar to those of N95 masks and are not acceptable for use in healthcare settings. Based on these results, and in consultation with occupational health officers, we make six recommendations for end users to assist in acquiring legitimate products. In particular, institutions should always assess masks from non-traditional supply chains by checking their markings and manufacturer information against data provided by NIOSH and the latest FDA EUA Appendix A. In the absence of verifiable information on the legitimacy of mask source, institutions should consider measuring mask fit and filtration directly. We also make suggestions for U.S and Chinese regulatory agencies with regard to labeling and public disclosure aimed at increase pandemic resilience.

3D Printed frames to enable reuse and improve the fit of N95 and KN95 respirators

BACKGROUND

In response to supply shortages during the COVID-19 pandemic, N95 filtering facepiece respirators (FFRs or "masks"), which are typically single-use devices in healthcare settings, are routinely being used for prolonged periods and in some cases decontaminated under "reuse" and "extended use" policies. However, the reusability of N95 masks is often limited by degradation or breakage of elastic head bands and issues with mask fit after repeated use. The purpose of this study was to develop a frame for N95 masks, using readily available materials and 3D printing, which could replace defective or broken bands and improve fit.

RESULTS

An iterative design process yielded a mask frame consisting of two 3D-printed side pieces, malleable wire links that users press against their face, and cut lengths of elastic material that go around the head to hold the frame and mask in place. Volunteers (n= 41; average BMI= 25.5), of whom 31 were women, underwent qualitative fit with and without mask frames and one or more of four different brands of FFRs conforming to US N95 or Chinese KN95 standards. Masks passed qualitative fit testing in the absence of a frame at rates varying from 48 - 92% (depending on mask model and tester). For individuals for whom a mask passed testing, 75-100% (average = 86%) also passed testing with a frame holding the mask in place. Among users for whom a mask failed in initial fit testing, 41% passed using a frame. Success varied with mask model and across individuals.

CONCLUSIONS

The use of mask frames can prolong the lifespan of N95 and KN95 masks by serving as a substitute for broken or defective bands without adversely affecting fit. Frames also have the potential to improve fit for some individuals who cannot fit existing masks. Frames therefore represent a simple and inexpensive way of extending the life and utility of PPE in short supply. For clinicians and institutions interested in mask frames, designs and specifications are provided without restriction for use or modification. To ensure adequate performance in clinical settings, qualitative fit testing with user-specific masks and frames is required.