Potential demand for respirators and surgical masks during a hypothetical influenza pandemic in the United States

Carbon footprint assessment of face masks in the context of the COVID-19 pandemic: Based on different protective performance and applicable scenarios

Widespread concerns have been raised about the huge environmental burden caused by massive consumption of face masks in the context of the COVID-19 pandemic. However, most of the existing studies only focus on the environmental impact associated with the product itself regardless of the actual usage scenarios and protective performance of products, resulting in unrealistic conclusions and poor applicability. In this context, this study integrated the product performance into the existing carbon footprint assessment methodology, with focus on the current global concerns regarding climate change. Computational case studies were conducted for different mask products applicable to the scenarios of low-, medium- and high-risk levels. The results showed that reusable cotton masks and disposable medical masks suitable for low-risk settings have a total carbon footprint of 285.484 kgCO₂-eq/FU and 128.926 kgCO₂-eq/FU respectively, with a break-even point of environmental performance between them of 16.886, which implies that cotton masks will reverse the trend and become more environmentally friendly after 17 washes, emphasizing the importance of improving the washability of cotton masks. Additionally, the total carbon footprints of disposable surgical masks and KN95 respirators were 154.328 kg CO₂-eq/FU and 641.249 kg CO₂-eq/FU respectively, while disposable medical masks and disposable surgical masks were identified as alternatives with better environmental performance in terms of medium- and high-risk environments respectively. The whole-life-cycle oriented carbon footprint evaluation further indicated that the four masks have greater potential for carbon emission reduction in the raw material processing and production processes. The results obtained in this study can provide scientific guidance for manufacturers and consumers on the production and use of protective masks. Moreover, the proposed model can be applied to other personal protective equipment with similar properties, such as protective clothing, in the future.

Flow-Shop Scheduling Problem Applied to the Planning of Repair and Maintenance of Electromedical Equipment in the Hospital Industry

In the literature, several approaches have been proposed to integrate and optimize product supply and construction processes associated with demand management. However, in Industry 4.0, there needs to be more studies related to applying techniques that directly affect the programming and reprogramming process that integrates the industries at the operational level. This document proposes a flow-shop scheduling procedure to address the problem of planning the repair of medical equipment in public hospitals whose main objective is to eliminate downtime and minimize total production time. The research stems from the practical problem of responding to clinical users who make use of critical equipment, such as mechanical respirators, due to COVID-19, and the limited quantity of this equipment, which makes it necessary to have repair planning processes that seek to keep the equipment in operation for the most extended amount of time. The novelty of this study is that it was applied to a critical and real problem in the industry with a high economic and social impact, which has not been explored previously. The results show improvements in the overall planning and execution of electro-medical equipment repair. Several improvements to the applied methods were identified as future work, such as the need to consider work interruptions and psychosocial effects on workers due to the stricter planning of execution times.

Fate of face masks after being discarded into seawater: Aging and microbial colonization

Billions of discarded masks have entered the oceans since the outbreak of the COVID-19 pandemic. Current reports mostly discuss the potential of masks as plastic pollution, but there has been no study on the fate of this emerging plastic waste in the marine environment. Therefore, we exposed masks in natural seawater and evaluated their aging and effects on the microbial community using a combination of physicochemical and biological techniques. After 30-day exposure in natural seawater, the masks suffered from significant aging. Microbial colonizers such as Rhodobacteraceae Flavobacteriaceae, Vibrionaceae and fouling organisms like calcareous tubeworms Hydroides elegans were massively present on the masks. The roughness and modulus of the mask fiber increased 3 and 5 times, respectively, and the molecular weight decreased 7%. The growth of biofouling organisms caused the masks negatively buoyant after 14-30 days. Our study sheds some light on the fate of discarded masks in a coastal area and provides fundamental data to manage this important plastic waste during COVID-19 pandemic.

Respirators in Healthcare: Material, Design, Regulatory, Environmental, and Economic Considerations for Clinical Efficacy

Maintaining an ample supply of personal protective equipment continues to be a challenge for the healthcare industry, especially during emergency situations and times of strain on the supply chain. Most critically, healthcare workers exposed to potential airborne hazards require sufficient respiratory protection. Respirators are the only type of personal protective equipment able to provide adequate respiratory protection. However, their ability to shield hazards depends on design, material, proper fit, and environmental conditions. As a result, not all respirators may be adequate for all scenarios. Additionally, factors including user comfort, ease of use, and cost contribute to respirator effectiveness. Therefore, a careful consideration of these parameters is essential for ensuring respiratory protection for those working in the healthcare industry. Here respirator design and material characteristics are reviewed, as well as properties of airborne hazards and potential filtration mechanisms, regulatory standards of governmental agencies, respirator efficacy in the clinical setting, attitude of healthcare personnel toward respiratory protection, and environmental and economic considerations of respirator manufacturing and distribution.

Fabrication and working of portable PPE kit sterilizer using UV Ozone Sanitization process

Personnel protective equipment, N95 masks, and filtering facepiece respirators such as goggles, face shields, played a very important rolein the safety of bothvirus-affected persons and as well as medical staff, health workers. As the coronavirus (Covid-19) was increasing exponentially worldwide, healthcare has been the demand for this basic equipment especiallyface protection shields have critical issues. There has been an effort to find out the different ways to conserve PPE kits, to use after the sterilization process. The current work focused onthe fabrication of the Portable PPE Kit Sterilizer model using UV Ozone Sanitization Processto utilize for recycling of N95 masks, goggles. Due to its miniature structure, can be used in public health sectors like the hospital, research centers, schools, and laboratories also. The method adopted was cheap, reuse, well suited for mass sanitization.

Filtering Facepiece Respirator Supply Chain Management Framework in a Disaster Such as COVID-19

Due to the lack of vaccines and treatments, filtering facepiece respirators are a primary and effective tool to dampen the spread of COVID-19. To meet the huge and continuous demand for filtering facepiece respirators, this concept paper suggests a supply chain management framework based on the disaster management principle. This concept paper adopts an exploratory and qualitative literature review to provide managerial insights for the supply chain participants. Due to implementation delay and strategic interdependency, the supply chain management strategies need to be systematically integrated. A viable way to integrate strategies is based on the disaster management cycle: mitigation, preparation, response, and recovery phases. Our model integrates innovative and successful but overlooked supply chain management strategies. First, the production capacity should be flexible so that the production mode in emergency and normal situations can be different. Second, the concept paper and development facilities can utilize their capacities for actual production in emergencies. Third, the quality certification process should accommodate the flexible production capacities. Fourth, inventory stockpiling should be renewable. This concept paper contributes to policymakers, healthcare sector decision-makers, stakeholders throughout the FFR supply chain to cope with future crises caused by pandemics by providing a systematic approach to constructing an effective, flexible, and resilient supply chain.

Principles and practice for SARS-CoV-2 decontamination of N95 masks with UV-C

A mainstay of personal protective equipment during the coronavirus disease 2019 pandemic is the N95 filtering facepiece respirator. N95 respirators are commonly used to protect healthcare workers from respiratory pathogens, including the novel coronavirus severe acute respiratory syndrome coronavirus 2, and are increasingly employed by other frontline workers and the general public. Under routine circumstances, these masks are disposable, single-use items, but extended use and reuse practices have been broadly enacted to alleviate critical supply shortages during the coronavirus disease 2019 pandemic. Although extended-time single use presents a low risk of pathogen transfer, repeated donning and doffing of potentially contaminated masks presents increased risk of pathogen transfer. Therefore, efficient and safe decontamination methods for N95 masks are needed to reduce the risk of reuse and mitigate local supply shortages. Here, we review the available literature concerning use of germicidal ultraviolet-C (UV-C) light to decontaminate N95 masks. We propose a practical method for repeated point-of-use decontamination using commercially available UV-C cross-linker boxes from molecular biology laboratories to expose each side of the mask to 800-1200 mJ/cm2 of UV-C. We measure the dose that penetrated to the interior of the respirators and model the potential germicidal action on coronaviruses. Our experimental results, in combination with modeled data, suggest that such a UV-C treatment cycle should induce a >3-log-order reduction in viral bioburden on the surface of the respirators and a 2-log-order reduction throughout the interior. We find that a dose 50-fold greater does not impair filtration or fit of 3M 8210 N95 masks, indicating that decontamination can be performed repeatedly. As such, UV-C germicidal irradiation is a practical strategy for small-scale point-of-use decontamination of N95s.

Thinking green: modelling respirator reuse strategies to reduce cost and waste

OBJECTIVES

To compare the impact of respirator extended use and reuse strategies with regard to cost and sustainability during the COVID-19 pandemic.

DESIGN

Cost analysis.

SETTING

USA.

PARTICIPANTS

All healthcare workers within the USA.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

A model was developed to estimate usage, costs and waste incurred by several respirator usage strategies over the first 6 months of the pandemic in the USA. This model assumed universal masking of all healthcare workers. Estimates were taken from the literature, government databases and commercially available data from approved vendors.

RESULTS

A new N95 respirator per patient encounter would require 7.41 billion respirators, cost $6.38 billion and generate 84.0 million kg of waste in the USA over 6 months. One respirator per day per healthcare worker would require 3.29 billion respirators, cost $2.83 billion and generate 37.22 million kg of waste. Decontamination by ultraviolet germicidal irradiation would require 1.64 billion respirators, cost $1.41 billion and accumulate 18.61 million kg of waste. H2O2 vapour decontamination would require 1.15 billion respirators, cost $1.65 billion and produce 13.03 million kg of waste. One reusable respirator with daily disposable filters would require 18 million respirators, cost $1.24 billion and generate 15.73 million kg of waste. Pairing a reusable respirator with H2O2 vapour-decontaminated filters would reduce cost to $831 million and generate 1.58 million kg of waste. The use of one surgical mask per healthcare worker per day would require 3.29 billion masks, cost $460 million and generate 27.92 million kg of waste.

CONCLUSIONS

Decontamination and reusable respirator-based strategies decreased the number of respirators used, costs and waste generated compared with single-use or daily extended-use of disposable respirators. Future development of low-cost,simple technologies to enable respirator and/or filter decontamination is needed to further minimise the economic and environmental costs of masks.

Unmasking the demand for masks: Analytics of mandating coronavirus masks

This paper analytically examines the demand for surgical masks following the recent health precautions due to coronavirus. Using a simple linear demand curve and alternatively examining the impacts of requirements that mandate (a) the wearing of masks by frontline workers; (b) suggested but not required masking by the whole public; and (c) compulsory masking by the whole public. The impacts of the different scenarios on the price elasticity of demand are determined along with the slope (or the rate of change) of elasticity. Some of these results differ when a non-linear demand curve is considered instead. The equilibrium mask prices increase when masks are universally mandated, whereas the consumer surplus is higher when masks are recommended but not mandated. However, the ranking of consumer surplus is shown to be sensitive to the supply elasticity of masks. These considerations enable a structured means to view the demand implications of masking requirements and provide some food for policy thought.

Personal respiratory protection and resiliency in a pandemic, the evolving disposable versus reusable debate and its effect on waste generation

The COVID-19 pandemic sweeping much of the globe is not anticipated to be short in duration, with contingency plans suggesting that it may last at least eighteen months. In the United States, one of the critical issues in coping with the pandemic has been a lack of essential personal protective equipment (PPE), at the local, state, and national level. As COVID-19 is primarily transferred through respiratory routes, adequate respiratory protection is a dire necessity. The shift from durable and reusable medical supplies in recent years to their single use counterparts has reduced the resiliency of the medical system with respect to PPE and other critical supplies in the current pandemic. This work explores the role of reusable compared to single use respiratory protection in the current pandemic, including reprocessing of single use options, from the perspective of number of equivalent protection devices needed. The current state of literature is also reviewed to provide context to this work, with respect to resource procurement. The economic cost of PPE throughout a pandemic is explored, and it is found that utilizing reusable PPE options depending on filter cycling may be less costly. Increased waste production is another issue with the current pandemic, and this is explored utilizing a mass basis, finding that reusable respiratory PPE would generate less waste than using single use PPE in a business as usual scenario. As future outbreaks of COVID-19 are likely along with other future pandemics, this work provides insights at how to prepare from the standpoint of PPE, and in particular respiratory protection.

Development, manufacturing, and preliminary validation of a reusable half-face respirator during the COVID-19 pandemic

Introduction

The COVID-19 pandemic has led to widespread shortages of N95 respirators and other personal protective equipment (PPE). An effective, reusable, locally-manufactured respirator can mitigate this problem. We describe the development, manufacture, and preliminary testing of an open-hardware-licensed device, the “simple silicone mask” (SSM).

Methods

A multidisciplinary team developed a reusable silicone half facepiece respirator over 9 prototype iterations. The manufacturing process consisted of 3D printing and silicone casting. Prototypes were assessed for comfort and breathability. Filtration was assessed by user seal checks and quantitative fit-testing according to CSA Z94.4–18.

Results

The respirator originally included a cartridge for holding filter material; this was modified to connect to standard heat-moisture exchange (HME) filters (N95 or greater) after the cartridge showed poor filtration performance due to flow acceleration around the filter edges, which was exacerbated by high filter resistance. All 8 HME-based iterations provided an adequate seal by user seal checks and achieved a pass rate of 87.5% (N = 8) on quantitative testing, with all failures occurring in the first iteration. The overall median fit-factor was 1662 (100 = pass). Estimated unit cost for a production run of 1000 using distributed manufacturing techniques is CAD $15 in materials and 20 minutes of labor.

Conclusion

Small-scale manufacturing of an effective, reusable N95 respirator during a pandemic is feasible and cost-effective. Required quantities of reusables are more predictable and less vulnerable to supply chain disruption than disposables. With further evaluation, such devices may be an alternative to disposable respirators during public health emergencies. The respirator described above is an investigational device and requires further evaluation and regulatory requirements before clinical deployment. The authors and affiliates do not endorse the use of this device at present.

Mitigating the Transmission of COVID-19 with the Appropriate Usage of Personal Protective Protocols and Equipment in Breast Imaging and Intervention

The integration of personal protective equipment (PPE) and procedures into breast imaging and intervention practices will mitigate the risk of transmission of COVID-19 during the pandemic. Although supply chain shortages have improved, understanding the proper use of PPE and protocols to mitigate overconsumption are important to ensure efficacious utilization of PPE. Protocols and best practices are reviewed, and guidelines and resource materials are referenced in order to support breast imaging healthcare professionals.

Analysis of SteraMist ionized hydrogen peroxide technology in the sterilization of N95 respirators and other PPE

The COVID-19 pandemic has led to widespread shortages of personal protective equipment (PPE) for healthcare workers, including of N95 masks (filtering facepiece respirators; FFRs). These masks are intended for single use but their sterilization and subsequent reuse has the potential to substantially mitigate shortages. Here we investigate PPE sterilization using ionized hydrogen peroxide (iHP), generated by SteraMist equipment (TOMI; Frederick, MD), in a sealed environment chamber. The efficacy of sterilization by iHP was assessed using bacterial spores in biological indicator assemblies. After one or more iHP treatments, five models of N95 masks from three manufacturers were assessed for retention of function based on their ability to form an airtight seal (measured using a quantitative fit test) and filter aerosolized particles. Filtration testing was performed at a university lab and at a National Institute for Occupational Safety and Health (NIOSH) pre-certification laboratory. The data demonstrate that N95 masks sterilized using SteraMist iHP technology retain filtration efficiency up to ten cycles, the maximum number tested to date. A typical iHP environment chamber with a volume of ~ 80 m3 can treat ~ 7000 masks and other items (e.g. other PPE, iPADs), making this an effective approach for a busy medical center.

Respiratory Protection in a Time of Crisis: NIOSH Testing of International Respiratory Protective Devices for Emergency Use

National Institute for Occupational Safety and Health (NIOSH)-approved respirators are required by the Occupational Safety and Health Administration (OSHA) when personal respiratory protection is used in US occupational settings. During the COVID-19 pandemic, the demand for NIOSH-approved N95 filtering facepiece respirators overwhelmed the available supply. To supplement the national inventory of N95 respirators, contingency and crisis capacity strategies were implemented and incorporated a component that endorsed the use of non-NIOSH-approved respiratory protective devices that conformed to select international standards. The development and execution of this strategy required the collaborative effort of numerous agencies. The Food and Drug Administration temporarily authorized non-NIOSH-approved international respiratory protective devices through an emergency use authorization, OSHA relaxed their enforcement guidance concerning their use in US workplaces, and NIOSH initiated a supplemental performance assessment process to verify the quality of international devices. NIOSH testing revealed that many of the non-NIOSH-approved respiratory protective devices had filtration efficiencies below 95% and substantial inconsistencies in filtration performance. This article reports the results of the NIOSH testing to date and discusses how it has contributed to continuous improvement of the crisis strategy of temporarily permitting the use of non-NIOSH-approved respirators in US occupational settings during the COVID-19 pandemic.

Contributing factors to personal protective equipment shortages during the COVID-19 pandemic

This study investigates the forces that contributed to severe shortages in personal protective equipment in the US during the COVID-19 crisis. Problems from a dysfunctional costing model in hospital operating systems were magnified by a very large demand shock triggered by acute need in healthcare and panicked marketplace behavior that depleted domestic PPE inventories. The lack of effective action on the part of the federal government to maintain and distribute domestic inventories, as well as severe disruptions to the PPE global supply chain, amplified the problem. Analysis of trade data shows that the US is the world's largest importer of face masks, eye protection, and medical gloves, making it highly vulnerable to disruptions in exports of medical supplies. We conclude that market prices are not appropriate mechanisms for rationing inputs to health because health is a public good. Removing the profit motive for purchasing PPE in hospital costing models, strengthening government capacity to maintain and distribute stockpiles, developing and enforcing regulations, and pursuing strategic industrial policy to reduce US dependence on imported PPE will help to better protect healthcare workers with adequate supplies of PPE.

Microwave- and heat-based decontamination of N95 filtering facepiece respirators: a systematic review

BACKGROUND

In pandemics such as COVID-19, shortages of personal protective equipment are common. One solution may be to decontaminate equipment such as facemasks for reuse.

AIM

To collect and synthesize existing information on decontamination of N95 filtering facepiece respirators (FFRs) using microwave and heat-based treatments, with special attention to impacts on mask function (aerosol penetration, airflow resistance), fit, and physical traits.

METHODS

A systematic review (PROSPERO CRD42020177036) of literature available from Medline, Embase, Global Health, and other sources was conducted. Records were screened independently by two reviewers, and data was extracted from studies that reported on effects of microwave- or heat-based decontamination on N95 FFR performance, fit, physical traits, and/or reductions in microbial load.

FINDINGS

Thirteen studies were included that used dry/moist microwave irradiation, heat, or autoclaving. All treatment types reduced pathogen load by a log₁₀ reduction factor of at least three when applied for sufficient duration (>30 s microwave, >60 min dry heat), with most studies assessing viral pathogens. Mask function (aerosol penetration <5% and airflow resistance <25 mmH₂O) was preserved after all treatments except autoclaving. Fit was maintained for most N95 models, though all treatment types caused observable physical damage to at least one model.

CONCLUSIONS

Microwave irradiation and heat may be safe and effective viral decontamination options for N95 FFR reuse during critical shortages. The evidence does not support autoclaving or high-heat (>90°C) approaches. Physical degradation may be an issue for certain mask models, and more real-world evidence on fit is needed.

Obstetrical Unit Response to the COVID-19 Pandemic: OUR Study

OBJECTIVE

This study aimed to describe the response of labor and delivery (L&D) units in the United States to the novel coronavirus disease 2019 (COVID-19) pandemic and determine how institutional characteristics and regional disease prevalence affect viral testing and personal protective equipment (PPE).

STUDY DESIGN

A cross-sectional survey was distributed electronically through the Society for Maternal-Fetal Medicine e-mail database (n = 584 distinct practices) and social media between April 14 and 23, 2020. Participants were recruited through "snowballing." A single representative was asked to respond on behalf of each L&D unit. Data were analyzed using Chi-square and Fisher's exact tests. Multivariable regression was performed to explore characteristics associated with universal testing and PPE usage.

RESULTS

A total of 301 surveys (estimated 51.5% response rate) was analyzed representing 48 states and two territories. Obstetrical units included academic (31%), community teaching (45%) and nonteaching hospitals (24%). Sixteen percent of respondents were from states with high prevalence, defined as higher "deaths per million" rates compared with the national average. Universal laboratory testing for admissions was reported for 40% (119/297) of units. After adjusting for covariates, universal testing was more common in academic institutions (adjusted odds ratio [aOR] = 1.73, 95% confidence interval [CI]: 1.23-2.42) and high prevalence states (aOR = 2.68, 95% CI: 1.37-5.28). When delivering asymptomatic patients, full PPE (including N95 mask) was recommended for vaginal deliveries in 33% and for cesarean delivery in 38% of responding institutions. N95 mask use during asymptomatic vaginal deliveries remained more likely in high prevalence states (aOR = 2.56, 95% CI: 1.29-5.09) and less likely in hospitals with universal testing (aOR = 0.42, 95% CI: 0.24-0.73).

CONCLUSION

Universal laboratory testing for COVID-19 is more common at academic institutions and in states with high disease prevalence. Centers with universal testing were less likely to recommend N95 masks for asymptomatic vaginal deliveries, suggesting that viral testing can play a role in guiding efficient PPE use.

KEY POINTS

· Heterogeneity is seen in institutional recommendations for viral testing and PPE.. · Universal laboratory testing for COVID-19 is more common at academic centers.. · N95 mask use during vaginal deliveries is less likely in places with universal testing..

Decontamination interventions for the reuse of surgical mask personal protective equipment: a systematic review

BACKGROUND

The high demand for personal protective equipment during the novel coronavirus outbreak has prompted the need to develop strategies to conserve supply. Little is known regarding decontamination interventions to allow for surgical mask reuse.

AIM

To identify and synthesize data from original research evaluating interventions to decontaminate surgical masks for the purpose of reuse.

METHODS

MEDLINE, Embase, CENTRAL, Global Health, the WHO COVID-19 database, Google Scholar, DisasterLit, preprint servers, and prominent journals from inception to April 8^th, 2020, were searched for prospective original research on decontamination interventions for surgical masks. Citation screening was conducted independently in duplicate. Study characteristics, interventions, and outcomes were extracted from included studies by two independent reviewers. Outcomes of interest included impact of decontamination interventions on surgical mask performance and germicidal effects.

FINDINGS

Seven studies met eligibility criteria: one evaluated the effects of heat and chemical interventions applied after mask use on mask performance, and six evaluated interventions applied prior to mask use to enhance antimicrobial properties and/or mask performance. Mask performance and germicidal effects were evaluated with heterogeneous test conditions. Safety outcomes were infrequently evaluated. Mask performance was best preserved with dry heat decontamination. Good germicidal effects were observed in salt-, N-halamine-, and nanoparticle-coated masks.

CONCLUSION

There is limited evidence on the safety or efficacy of surgical mask decontamination. Given the heterogeneous methods used in studies to date, we are unable to draw conclusions on the most efficacious and safe intervention for decontaminating surgical masks.

Social Media Survey and Web Posting Assessment of the COVID-19 Response in China: Health Worker Attitudes Toward Preparedness and Personal Protective Equipment Shortages

BACKGROUND

Understanding health worker awareness, attitudes, and self-confidence in the workplace can inform local and global responses toward emerging infectious threats, like the coronavirus disease 2019 (COVID-19) pandemic. Availability of accessible personal protective equipment (PPE) is vital to effective care and prevention.

METHODS

We conducted a cross-sectional survey from February 24 to 28, 2020, to assess COVID-19 preparedness among health workers. In addition, we assessed trends from search engine web crawling and text-mining data trending over the Sina Weibo platform from January 1 to March 3, 2020. Data were abstracted on Chinese outbreak preparedness.

RESULTS

In the survey, we engaged 6350 persons, of whom 1065 agreed to participate, and after an eligibility logic check, 1052 participated (16.6%). We accessed 412 internet posts as to PPE availability. Health workers who were satisfied with current preparedness to address COVID-19 were more likely to be female, to obtain knowledge about the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak from government organizations, and to consider their hospital prepared for outbreak management. Health workers with more confidence in their abilities to respond were those with more faith in their institution's response capacities. Elements of readiness included having airborne infection isolation rooms, visitor control procedures, and training in precautions and PPE use. Both survey and web post assessments suggested that health workers in need were unable to reliably obtain PPE.

CONCLUSIONS

Health workers' self-confidence depends on perceived institutional readiness. Failure to maintain available PPE inventory for emerging infectious diseases preparedness suggests a failure to learn key lessons from the 2003-2004 SARS outbreak in China.

Strategies for Optimizing the Supply of N95 Filtering Facepiece Respirators During the Coronavirus Disease 2019 (COVID-19) Pandemic

N95 respirators are personal protective equipment most often used to control exposures to infections transmitted via the airborne route. Supplies of N95 respirators can become depleted during pandemics or when otherwise in high demand. In this paper, we offer strategies for optimizing supplies of N95 respirators in health care settings while maximizing the level of protection offered to health care personnel when there is limited supply in the United States during the 2019 coronavirus disease pandemic. The strategies are intended for use by professionals who manage respiratory protection programs, occupational health services, and infection prevention programs in health care facilities to protect health care personnel from job-related risks of exposure to infectious respiratory illnesses. Consultation with federal, state, and local public health officials is also important. We use the framework of surge capacity and the occupational health and safety hierarchy of controls approach to discuss specific engineering control, administrative control, and personal protective equipment measures that may help in optimizing N95 respirator supplies.

Decontamination interventions for the reuse of surgical mask personal protective equipment: a systematic review

BACKGROUND

The high demand for personal protective equipment during the novel coronavirus outbreak has prompted the need to develop strategies to conserve supply. Little is known regarding decontamination interventions to allow for surgical mask reuse.

AIM

To identify and synthesize data from original research evaluating interventions to decontaminate surgical masks for the purpose of reuse.

METHODS

MEDLINE, Embase, CENTRAL, Global Health, the WHO COVID-19 database, Google Scholar, DisasterLit, preprint servers, and prominent journals from inception to April 8^th, 2020, were searched for prospective original research on decontamination interventions for surgical masks. Citation screening was conducted independently in duplicate. Study characteristics, interventions, and outcomes were extracted from included studies by two independent reviewers. Outcomes of interest included impact of decontamination interventions on surgical mask performance and germicidal effects.

FINDINGS

Seven studies met eligibility criteria: one evaluated the effects of heat and chemical interventions applied after mask use on mask performance, and six evaluated interventions applied prior to mask use to enhance antimicrobial properties and/or mask performance. Mask performance and germicidal effects were evaluated with heterogeneous test conditions. Safety outcomes were infrequently evaluated. Mask performance was best preserved with dry heat decontamination. Good germicidal effects were observed in salt-, N-halamine-, and nanoparticle-coated masks.

CONCLUSION

There is limited evidence on the safety or efficacy of surgical mask decontamination. Given the heterogeneous methods used in studies to date, we are unable to draw conclusions on the most efficacious and safe intervention for decontaminating surgical masks.

Mask Reuse in the COVID-19 Pandemic: Creating an Inexpensive and Scalable Ultraviolet System for Filtering Facepiece Respirator Decontamination

As the current COVID-19 pandemic illustrates, not all hospitals and other patient care facilities are equipped with enough personal protective equipment to meet the demand in a crisis. Health care workers around the world use filtering facepiece respirators to protect themselves and their patients, yet during this global pandemic they are forced to reuse what are intended to be single-use masks. This poses a significant risk to these health care workers along with the people they are trying to protect. Ultraviolet germicidal irradiation (UVGI) has been validated previously as a method to effectively decontaminate these masks between use. However, not all facilities have access to the expensive commercial ultraviolet type C (UV-C) lamp decontamination equipment required for UVGI. UV-C bulbs are sitting idle in biosafety cabinets at universities and research facilities around the world that have been shuttered to slow the spread of COVID-19. These bulbs may also be available in existing medical centers where infectious diseases are commonly treated. We developed a method to modify existing light fixtures or create custom light fixtures that are compatible with new or existing UV-C bulbs. This system is scalable; can be created for less than US$50, on site and at the point of need; and leverages resources that are currently untapped and sitting unused in public and private research facilities during the pandemic. The freely accessible design can be easily modified for use around the world. Health care facilities can obtain this potentially lifesaving UVGI resource with minimal funds by collaborating with research facilities to obtain the UV-C meters and UV-C bulbs if they are unavailable from other sources. Although mask reuse is not ideal, we must do what we can in emergency situations to protect our health care workers responding to the pandemic and the communities they serve.

Home-made masks with filtration efficiency for nano-aerosols for community mitigation of COVID-19 pandemic

Objectives

The novel coronavirus disease 2019 (COVID-19) epidemic that emerged in December 2019 has rapidly evolved in recent months to become a worldwide and ongoing pandemic. Shortage of medical masks remains an unresolved problem. This study aims to investigate the filtration efficiency (FE) of home-made masks that could be used as alternatives for community mitigation of COVID-19.

Study design

Experimental observational analytic study.

Methods

The FE of home-made masks and medical masks (as the control) were tested under laminar flow within a scaled air duct system using nebulised NaCl aerosols sized 6–220 nm. The size-resolved NaCl aerosol count was measured using a scanning mobility particle-sizer spectrometer. Home-made masks with an external plastic face shield also underwent a splash test. In addition, the fibre structures of medical masks were studied under an electron microscope after treatment with either 75% alcohol or soap and water at 60 °C.

Results

The FE of the home-made masks at 6–200 nm were non-inferior to that of medical masks (84.54% vs 86.94%, P = 0.102). Both types of masks achieved an FE of 90% at 6–89 nm. A significantly higher FE was achieved when one piece of tissue paper was added adjacent to the inner surface of the medical mask than medical mask alone (6–200 nm: 91.64% vs 86.94%, P < 0.0001; 6–89 nm: 94.27% vs 90.54%, P < 0.0001; 90–200 nm: 82.69% vs 73.81%, P < 0.0001). The plastic face shield prevented the home-made mask from fluid splash. The fibre structures of the external surface of medical masks were damaged after treatment with either 75% alcohol or soap and water at 60 °C.

Conclusions

The home-made masks in this study, which were made of one piece of tissue paper and two pieces of kitchen towels, layered from face to external, had an FE at 6–200 nm non-inferior to that of medical mask materials, which had a certified FE of ≥95% at 3 μm. In the current COVID-19 pandemic with the shortage of medical masks, these home-made masks combined with an external plastic shield could be used as an alternative to medical masks for community mitigation. In addition, one piece of tissue paper could be placed adjacent to the inner surface of a medical mask to prolong effective lifespan of the medical mask. These demand reduction strategies could be used to reserve medical masks for use in healthcare and certain high-risk community settings, such as symptomatic persons, caregivers and attendees to healthcare institutions.

•

Our home-made masks have filtration efficiency comparable to medical masks.

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They may be used as alternatives in low-risk community settings.

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Plastic face shields may be used in situations when social distancing and/or face masks are not feasible.

•

Decontamination of medical masks with 75% alcohol or soap and water damages the fibres and is not recommended.

•

Community mitigation measures are an important part of the global efforts in combating COVID-19.

Mask or no mask for COVID-19: A public health and market study

Efficient strategies to contain the coronavirus disease 2019 (COVID-19) pandemic are peremptory to relieve the negatively impacted public health and global economy, with the full scope yet to unfold. In the absence of highly effective drugs, vaccines, and abundant medical resources, many measures are used to manage the infection rate and avoid exhausting limited hospital resources. Wearing masks is among the non-pharmaceutical intervention (NPI) measures that could be effectively implemented at a minimum cost and without dramatically disrupting social practices. The mask-wearing guidelines vary significantly across countries. Regardless of the debates in the medical community and the global mask production shortage, more countries and regions are moving forward with recommendations or mandates to wear masks in public. Our study combines mathematical modeling and existing scientific evidence to evaluate the potential impact of the utilization of normal medical masks in public to combat the COVID-19 pandemic. We consider three key factors that contribute to the effectiveness of wearing a quality mask in reducing the transmission risk, including the mask aerosol reduction rate, mask population coverage, and mask availability. We first simulate the impact of these three factors on the virus reproduction number and infection attack rate in a general population. Using the intervened viral transmission route by wearing a mask, we further model the impact of mask-wearing on the epidemic curve with increasing mask awareness and availability. Our study indicates that wearing a face mask can be effectively combined with social distancing to flatten the epidemic curve. Wearing a mask presents a rational way to implement as an NPI to combat COVID-19. We recognize our study provides a projection based only on currently available data and estimates potential probabilities. As such, our model warrants further validation studies.

COVID-19 in the UK and Occupational Health and Safety: Predictable not Inevitable Failures by Government, and Trade Union and Nongovernmental Organization Responses

This commentary examines the occupational health and safety issues faced by the UK workers in the COVID-19 pandemic, against the background of government cuts in health care and in occupational health and safety budgets, and a deregulatory climate. The UK government has been obsessed, blinkered, and distracted by the desire to leave the European Union (Brexit). The state of knowledge about the virus, especially from international agencies that identified pandemic threats and strategies to combat it, is outlined. UK politicians, government bodies, medical and scientific advisors, and employers periodically ignored or abused that knowledge. Regulatory and ministerial inaction and errors on the workplace virus risks emerged. In contrast, several trade unions, health professional bodies, and nongovernmental organizations identified COVID-19 threats from poor personal protection equipment, working practices, and knowledge gaps and offered solutions for health care workers, social care workers, production workers, and service workers in "essential" occupations.

Evidence for decontamination of single-use filtering facepiece respirators

Single-use filtering face respirators (FFRs) are critical pieces of personal protective equipment for healthcare workers treating patients with suspected upper respiratory tract pathogens. Experiences during pandemics in the 2000s, as well as the ongoing COVID-19 pandemic caused by the SARS-2-CoV-2, have highlighted concerns over the pressures that sustained respiratory virus pandemics may have on supplies of FFRs globally. Decontamination of FFRs has been posited as one solution to support the re-use of FFRs with a growing body of literature over the last 10+ years beginning to examine both the efficacy of disinfection of contaminated FFRs but also the impact of the decontamination process on the FFR's performance. Physical and chemical methods of decontamination have been tested for treatment of FFRs with ultraviolet germicidal irradiation, sterilization by steam, ethylene oxide and vaporous hydrogen peroxide, demonstrating the most promising results thus far. Many of these methods utilize existing equipment that may already be available in hospitals and could be re-purposed for FFR decontamination. Importantly, some methods may also be replicated on household equipment, broadening the utility of FFR decontamination across a range of healthcare settings. Utilizing techniques to experimentally contaminate FFRs with a range of microorganisms, most decontamination methods appear to reduce the risk of the mask as a source of infection to the wearer and others to negligible levels. The performance of the filter, especially the efficiency of particle penetration following treatment, varied greatly depending on the processing method as well as the model of the filter itself, however. Urgent regulatory body-supported research is required to endorse the routine decontamination of FFRs. In emergency settings, these methods should nevertheless be carefully considered as one strategy to address potential shortfalls in supplies of FFRs for healthcare workers.

The use of exhaled nitric oxide and peak expiratory flow to demonstrate improved breathability and antimicrobial properties of novel face mask made with sustainable filter paper and Folium Plectranthii amboinicii oil: additional option for mask shortage during COVID-19 pandemic

Background

Medical face masks are integral personal protective equipment against infectious airborne disease and become scarce during epidemic outbreaks such as COVID-19. A novel, sustainably manufactured face mask with antimicrobial and anti-inflammatory properties from oil of Folium Plectranthii amboinicii can be an effective alternative to internationally sold masks.

Methods

This prospective, randomized study assigned subjects (n=67) to either conventional surgical face mask or Lamdong Medical College (LMC) face mask for three hours. Fractional concentration of nitric oxide in exhaled breath (FE_NO) and peak expiratory flow (PEF) was measured before and after mask use. Subjective reporting on respiratory symptoms was also analyzed. Masks were then incubated and analyzed for microorganism growth.

Results

Subjects assigned the LMC mask had a lowered FE_NO (p<0.05) compared to conventional face masks after mask wearing. Subjects with LMC mask use reported higher comfortability (p<0.05), breathability (p<0.05), and lower allergy symptoms (p<0.05). The LMC mask has visually less microorganism growth in the cultured medium, measured by sterile ring radius.

Conclusions

The LMC face mask is a renewably manufactured personal protective tool with antibacterial capacity that can serve as an effective alternative to internationally sold surgical face mask during shortage of mask due to COVID-19.

Quality Assurance Sampling Plans in US Stockpiles for Personal Protective Equipment: A Computer Simulation to Examine Degradation Rates

Medical countermeasure stockpiles in the United States are designed to support healthcare workers and the public during public health emergencies; they include supplies of personal protective equipment (PPE). As part of typical PPE manufacturing processes, appropriate test methods are used to ensure that the devices provide adequate protective performance. At the time of manufacture, performance is often measured and weighed against an objective standard of quality, resulting in a pass or fail attribute being assigned to individual PPE items and thence to production lots. Incorporating periodic performance testing for stockpiled PPE can ensure that they maintain their protective qualities and integrity over time while in storage. There is an absence of guidance regarding how to design quality assurance programs for stockpiled PPE. The applicability of the Lot Quality Assurance Sampling (LQAS) approach to stockpiled PPE was examined in a previous study that compared and contrasted different sample sizes in recovering the true percentage of defective units in large lots in the LQAS framework. The current study carries this line of inquiry forward by integrating PPE degradation over time and comparing different sampling time intervals in recovering the true underlying degradation rate. The results suggest that product degradation is more easily detected when tested at shorter time intervals and for higher degradation rates. They further suggest that sampling interval groupings can be made based on the proficiency with which they recover the true underlying degradation rate.

Facial protection for healthcare workers during pandemics: a scoping review

Background

The coronavirus disease 2019 (COVID-19) pandemic has led to personal protective equipment (PPE) shortages, requiring mask reuse or improvisation. We provide a review of medical-grade facial protection (surgical masks, N95 respirators and face shields) for healthcare workers, the safety and efficacy of decontamination methods, and the utility of alternative strategies in emergency shortages or resource-scarce settings.

Methods

We conducted a scoping review of PubMed and grey literature related to facial protection and potential adaptation strategies in the setting of PPE shortages (January 2000 to March 2020). Limitations included few COVID-19-specific studies and exclusion of non-English language articles. We conducted a narrative synthesis of the evidence based on relevant healthcare settings to increase practical utility in decision-making.

Results

We retrieved 5462 peer-reviewed articles and 41 grey literature records. In total, we included 67 records which met inclusion criteria. Compared with surgical masks, N95 respirators perform better in laboratory testing, may provide superior protection in inpatient settings and perform equivalently in outpatient settings. Surgical mask and N95 respirator conservation strategies include extended use, reuse or decontamination, but these strategies may result in inferior protection. Limited evidence suggests that reused and improvised masks should be used when medical-grade protection is unavailable.

Conclusion

The COVID-19 pandemic has led to critical shortages of medical-grade PPE. Alternative forms of facial protection offer inferior protection. More robust evidence is required on different types of medical-grade facial protection. As research on COVID-19 advances, investigators should continue to examine the impact on alternatives of medical-grade facial protection.

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

OBJECTIVE

The COVID-19 pandemic has led to widespread shortages of personal protective equipment (PPE) for healthcare workers, including filtering facepiece respirators (FFRs) such as N95 masks. These masks are normally intended for single use, but their sterilization and subsequent reuse could substantially mitigate a world-wide shortage.

DESIGN

Quality assurance.

SETTING

A sealed environment chamber installed in the animal facility of an academic medical center.

INTERVENTIONS

One to five sterilization cycles using ionized hydrogen peroxide (iHP), generated by SteraMist equipment (TOMI; Frederick, MD).

MAIN OUTCOME MEASURES

Personal protective equipment, including five N95 mask models from three manufacturers, were evaluated for efficacy of sterilization following iHP treatment (measured with bacterial spores in standard biological indicator assemblies). Additionally, N95 masks were assessed for their ability to efficiently filter particles down to 0.3um and for their ability to form an airtight seal using a quantitative fit test. Filtration efficiency was measured using ambient particulate matter at a university lab and an aerosolized NaCl challenge at a National Institute for Occupational Safety and Health (NIOSH) pre-certification laboratory.

RESULTS

The data demonstrate that N95 masks sterilized using SteraMist iHP technology retain function up to five cycles, the maximum number tested to date. Some but not all PPE could also be sterilized using an iHP environmental chamber, but pre-treatment with a handheld iHP generator was required for semi-enclosed surfaces such as respirator hoses.

CONCLUSIONS

A typical iHP environment chamber with a volume of ~80 m3 can treat ~7000 masks per day, as well as other items of PPE, making this an effective approach for a busy medical center.

A General Framework to Test and Evaluate Filtering Facepiece Respirators Considered for Crisis Capacity Use as a Strategy to Optimize Supply

During a public health emergency, respirator shortages can have a profound impact on the national response, such as for the current coronavirus disease 2019 (COVID-19) pandemic. Due to a severe shortage of respirators (particularly filtering facepiece respirators [FFRs]), there may be contexts in which understanding the performance of FFRs that are approved for use as part of a crisis capacity strategy is desired. This includes FFRs that are not covered under the National Institute for Occupational Safety and Health (NIOSH) Respirator Approval Program because they have been stored past their designated shelf life, have been decontaminated, or are approved by international certification bodies other than NIOSH. The purpose of this document is to provide a general framework to assess the performance of FFRs that are only being used as a crisis capacity strategy. The intended audience are those who are responsible for managing large amounts of FFRs. This framework includes a four-step process consisting of: 1) defining the population of FFRs to be sampled; 2) providing sampling strategy options; 3) inspecting and testing the sampled units; and 4) evaluating the results. In addition to the four-step process, we provide an example of how NIOSH recently evaluated the quality of FFRs sampled from ten U.S. stockpiles.

Face Masks in the New COVID-19 Normal: Materials, Testing, and Perspectives

The increasing prevalence of infectious diseases in recent decades has posed a serious threat to public health. Routes of transmission differ, but the respiratory droplet or airborne route has the greatest potential to disrupt social intercourse, while being amenable to prevention by the humble face mask. Different types of masks give different levels of protection to the user. The ongoing COVID-19 pandemic has even resulted in a global shortage of face masks and the raw materials that go into them, driving individuals to self-produce masks from household items. At the same time, research has been accelerated towards improving the quality and performance of face masks, e.g., by introducing properties such as antimicrobial activity and superhydrophobicity. This review will cover mask-wearing from the public health perspective, the technical details of commercial and home-made masks, and recent advances in mask engineering, disinfection, and materials and discuss the sustainability of mask-wearing and mask production into the future.

Planning for Epidemics and Pandemics: Assessing the Potential Impact of Extended Use and Reuse Strategies on Respirator Usage Rates to Support Supply-and-Demand Planning Efforts

During epidemics and pandemics healthcare personnel (HCP) are on the front line of disease containment and mitigation. Personal protective equipment (PPE), such as NIOSH-approved N95 filtering facepiece respirators (FFRs), serve an important role in minimizing HCP risks and are in high demand during public health emergencies. Because PPE demand can exceed supply, various public health strategies have been developed to reduce the rate of PPE consumption as supply dwindles. Extended use and limited reuse of N95 FFRs are strategies advocated by many governmental agencies used to increase the number of times a device can be used. Increased use of respirators designed for reuse-such as powered air-purifying respirators (PAPRs) and elastomeric half-mask and full facepiece air-purifying respirators- is another option designed to reduce the continuous need for new devices as the daily need for respirator use increases. Together, these strategies are designed to reduce the number of PPE units that must be discarded daily and, therefore, extend the longevity of available supply. The purpose of this paper is to theoretically estimate the impact of extended use and limited reuse strategies for N95 FFRs and the increased use of reusable respirator options on PPE consumed. The results suggest that a considerable reduction in PPE consumption would result from extended use and limited reuse of N95 FFRs and the increased use of respirators designed for reuse; however, the practical benefits must be balanced with the risks and economic costs. In addition, extended use and reuse strategies must be accompanied by proper procedures to reduce risk. The study is designed to support epidemic and pandemic PPE supply and demand planning efforts.

A pilot study of minimum operational flow for loose-fitting powered air-purifying respirators used in healthcare cleaning services

The objective of this pilot study was to determine the minimum operational flow for loose-fitting powered air-purifying respirators (PAPR) used in healthcare cleaning services. An innovative respiratory flow recording device was worn by nine healthcare workers to obtain the minute volume (MV, L/min), mean inhalation flow (MIF, L/min), and peak inhalation flow (PIF, L/min) while performing "isolation unit work" (cleaning and disinfecting) of a patient room within 30 min. The MV and PIF were compared with the theoretical values obtained from an empirical formula. The correlations of MV, MIF, and PIF with subjects' age, weight, height, body surface area (A_Du), and body mass index (BMI) were analyzed. The average MV, MIF, and PIF were 33, 74, and 107 L/min, with maximal airflow rates of 41, 97, and 145 L/min, respectively, which are all below the current 170 L/min minimum operational flow for NIOSH certified loose-fitting PAPRs.

Quality Assurance Sampling Plans in US Stockpiles for Personal Protective Equipment

Personal protective equipment (PPE) stockpiles in the United States were established to facilitate rapid deployment of medical assets to sites affected by public health emergencies. Large quantities of PPE were introduced into US stockpiles because of the need to protect healthcare and other professionals during these events. Because most stockpiled PPE was acquired during, or immediately following, large-scale public health events, such as pandemic influenza planning (2005-20080), SARS (2003), H1N1 (2009-10), and Ebola (2014-15), aging PPE poses a significant problem. PPE such as N95 filtering face piece respirators were not designed to be stored for long periods, and much of the currently stored PPE has exceeded its manufacturer-assigned shelf life. Given the significant investment in the procurement and storage of PPE, along with projections of consumption during public health emergencies, discarding large quantities of potentially viable PPE is not an attractive option. Although shelf-life extension programs exist for other stockpiled medical assets, no such option is currently available for stockpiled PPE. This article posits stockpile quality assurance sampling plans as a mechanism through which shelf-life extension programs for stockpiled PPE may be achieved. We discuss some of the nuances that should be considered when developing a plan tailored to stockpiles and provide basic decision tools that may be used in the context of a quality assurance program tailored to stockpiled PPE. We also explore basic information by comparing and contrasting different sample size options.

A Control Banding Framework for Protecting the US Workforce from Aerosol Transmissible Infectious Disease Outbreaks with High Public Health Consequences

Recent high-profile infectious disease outbreaks illustrate the importance of selecting appropriate control measures to protect a wider range of employees, other than those in healthcare settings. In such settings, where routine exposure risks are often high, control measures may be more available, routinely implemented, and studied for effectiveness. In the absence of evidence-based guidelines or established best practices for selecting appropriate control measures, employers may unduly rely on personal protective equipment (PPE) because of its wide availability and pervasiveness as a control measure, circumventing other effective options for protection. Control banding is one approach that may be used to assign job tasks into risk categories and prioritize the application of controls. This article proposes an initial control banding framework for workers at all levels of risk and incorporates a range of control options, including PPE. Using the National Institutes of Health (NIH) risk groups as a surrogate for toxicity and combining the exposure duration with the exposure likelihood, we can generate the risk of a job task to the worker.

A tolerability assessment of new respiratory protective devices developed for health care personnel: A randomized simulated clinical study

BACKGROUND

U.S. health care personnel (HCP) have reported that some respiratory protective devices (RPD) commonly used in health care have suboptimal tolerability. Between 2012 and 2016, the U.S. National Institute for Occupational Safety and Health, and the Veterans Health Administration collaborated with two respirator manufacturers, Company A and B, to bring new RPD with improved tolerability to the U.S. health care marketplace. The purpose of this study was to compare the tolerability of four new prototype RPD to two models commonly used in U.S. health care delivery.

METHODS

A randomized, simulated workplace study was conducted to compare self-reported tolerability of four new prototype RPD (A1, A2, B1, and B2) worn by HCP and two N95 control respirators commonly used in U.S. health care delivery, the 1870 and 1860, manufactured by 3M Corporation. A new survey tool, the Respirator Comfort, Wearing Experience, and Function Instrument (R-COMFI), developed previously in part for the current study, was used as the primary outcome metric. With a maximum total score of 47, lower R-COMFI scores reflected better self-reported tolerability. Poisson regression analyses were used to estimate prototype relative risks compared to controls.

RESULTS

Conducted between 2014 and 2015 in two inpatient care rooms at the North Florida/South Georgia Veterans Health System, among 383 participants who enrolled, 335 (87.5%) completed the study. Mean total R-COMFI scores for the 3M 1870, 3M 1860, and prototypes A1, A2, B1, and B2 were 8.26, 9.36, 5.79, 7.70, 6.09, and 5.71, respectively. Compared to the 3M 1870, total R-COMFI unadjusted relative risks (RR) and 95 percent confidence intervals (CI) were A1 (RR 0.70, CI 0.60, 0.82), A2 (RR 0.93, CI 0.82, 1.06), B1 (RR 0.74, CI 0.64, 0.85), and B2 (RR 0.69, CI 0.60, 0.80). Compared to the 3M 1860, prototype total R-COMFI unadjusted RR and 95 percent CI were A1 (RR 0.62, CI 0.53, 0.72), A2 (RR 0.82, CI 0.73, 0.93), B1 (RR 0.65, CI 0.57, 0.74), and B2 (RR 0.61, CI 0.53, 0.70). Similarly, models adjusted for demographic characteristics showed that prototypes A1, B1, and B2 significantly improved tolerability scores compared to both controls, while prototype A2 was significantly improved compared to the 3M 1860.

CONCLUSIONS

Compared to the 3M 1870 and 3M 1860, two RPDs commonly used in U.S. health care delivery, tolerability improved for three of four newly developed prototypes in this simulated workplace study. The R-COMFI tool, used in this study to assess tolerability, should be useful for future comparative studies of RPD.

Assessment of environmental and surgical mask contamination at a student health center - 2012-2013 influenza season

Increased understanding of influenza transmission is critical for pandemic planning and selecting appropriate controls for healthcare personnel safety and health. The goals of this pilot study were to assess environmental contamination in different areas and at two time periods in the influenza season and to determine the feasibility of using surgical mask contamination to evaluate potential exposure to influenza virus. Bioaerosol samples were collected over 12 days (two 6-day sessions) at 12 locations within a student health center using portable two-stage bioaerosol samplers operating 8 hr each day. Surface samples were collected each morning and afternoon from common high-contact non-porous hard surfaces from rooms and locations where bioaerosol samplers were located. Surgical masks worn by participants while in contact with patients with influenza-like illness were collected. A questionnaire administered to each of the 12 participants at the end of each workday and another at the end of each workweek assessed influenza-like illness symptoms, estimated the number of influenza-like illness patient contacts, hand hygiene, and surgical mask usage. All samples were analyzed using qPCR. Over the 12 days of the study, three of the 127 (2.4%) bioaerosol samples, 2 of 483 (0.41%) surface samples, and 0 of 54 surgical masks were positive for influenza virus. For the duration of contact that occurred with an influenza patient on any of the 12 days, nurse practitioners and physicians reported contacts with influenza-like illness patients >60 min, medical assistants reported 15-44 min, and administrative staff reported <30 min. Given the limited number of bioaerosol and surface samples positive for influenza virus in the bioaerosol and surface samples, the absence of influenza virus on the surgical masks provides inconclusive evidence for the potential to use surgical masks to assess exposure to influenza viruses. Further studies are needed to determine feasibility of this approach in assessing healthcare personnel exposures. Information learned in this study can inform future field studies on influenza transmission.

Ultraviolet germicidal irradiation of influenza-contaminated N95 filtering facepiece respirators

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Ultraviolet light can significantly reduce viable influenza on N95 respirators.

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Ultraviolet decontamination of N95 respirators can vary between models.

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Straps of N95 respirators are challenging to decontaminate using ultraviolet light.

Background

Safe and effective decontamination and reuse of N95 filtering facepiece respirators (FFRs) has the potential to significantly extend FFR holdings, mitigating a potential shortage due to an influenza pandemic or other pandemic events. Ultraviolet germicidal irradiation (UVGI) has been shown to be effective for decontaminating influenza-contaminated FFRs. This study aims to build on past research by evaluating the UVGI decontamination efficiency of influenza-contaminated FFRs in the presence of soiling agents using an optimized UVGI dose.

Methods

Twelve samples each of 15 N95 FFR models were contaminated with H1N1 influenza (facepiece and strap), then covered with a soiling agent—artificial saliva or artificial skin oil. For each soiling agent, 3 contaminated FFRs were treated with 1 J/cm² UVGI for approximately 1 minute, whereas 3 other contaminated FFRs remained untreated. All contaminated surfaces were cut out and virus extracted. Viable influenza was quantified using a median tissue culture infectious dose assay.

Results

Significant reductions (≥3 log) in influenza viability for both soiling conditions were observed on facepieces from 12 of 15 FFR models and straps from 7 of 15 FFR models.

Conclusions

These data suggest that FFR decontamination and reuse using UVGI can be effective. Implementation of a UVGI method will require careful consideration of FFR model, material type, and design.

Feasibility Assessment of a New Surveillance Tool for Respiratory Protective Devices Used in U.S. Healthcare

BACKGROUND

Respiratory protective devices (RPDs) are used for infection prevention in healthcare settings during routine patient care and public health emergencies. In recent years, healthcare systems have experienced shortages of RPDs during outbreaks of infectious diseases, in part due to a lack of information about their availability. New tools to track RPD inventories may improve accessibility during an emergency. Investigators at Vanderbilt University have identified four major themes that influence RPD use for infection prevention: hospital preparedness, responsiveness to airborne pathogens, potential exposure outcomes, and infection control practices related to respirator effectiveness. Based on these findings, an RPD surveillance tool (RST) was developed to collect and share near real-time data about RPD supplies in healthcare facilities. The objective of this study was to conduct a feasibility assessment of this RST.

METHODS

The new online surveillance tool was implemented at four large, urban, acute care U.S. hospitals in January 2014; data was collected about RPD inventory, tracking systems, hospital characteristics, and utility of gathered information.

RESULTS

The RST was implemented successfully and without difficulty at hospitals that had 78 to 90 percent occupancy rates. Participating hospitals reported that the RST (1) provided value for benchmarking their RPD supply, (2) promoted understanding about RPD accessibility among hospital systems engaged in infection control, and (3) served as a means to assess RPD program quality.

CONCLUSION

Implementation of this newly developed RST is feasible and appears to have utility in U.S. hospitals for tracking and understanding RPD use for routine healthcare delivery and public health emergencies.

Relative survival of Bacillus subtilis spores loaded on filtering facepiece respirators after five decontamination methods

This study determines the relative survival (RS) of Bacillus subtilis spores loaded on an N95 filtering facepiece respirator (FFR) after decontamination by five methods under worst-case conditions. Relative survival was obtained by testing after decontamination and after storing the FFRs at 37°C and 95% relative humidity for 24 hours. The decontamination methods involved ethanol, bleach, ultraviolet irradiation (UVA 365 nm, UVC 254 nm), an autoclave, and a traditional electric rice cooker (TERC) that was made in Taiwan. Without decontamination, 59 ± 8% of the loaded spores survived for 24 hours. When 70% ethanol was added to the N95 FFR at a packing density of 0.23, the RS was 73 ± 5% initially and decayed to 22 ± 8% in 24 hours. Relative survival remained above 20% after 20 minutes of UVA irradiation. The other four decontamination measures achieved 99%-100% biocidal efficacy, as measured immediately after the methods were applied to the test FFRs. Relative survival is a useful parameter for measuring sterilization or degree of disinfection. Bleach, UVC, an autoclave, and a TERC provide better biocidal efficacy than ethanol and UVA. Not only a higher filter quality but also a lower value of RS produced the most decontaminated FFR.

Personal Protective Equipment Supply Chain: Lessons Learned from Recent Public Health Emergency Responses

Personal protective equipment (PPE) that protects healthcare workers from infection is a critical component of infection control strategies in healthcare settings. During a public health emergency response, protecting healthcare workers from infectious disease is essential, given that they provide clinical care to those who fall ill, have a high risk of exposure, and need to be assured of occupational safety. Like most goods in the United States, the PPE market supply is based on demand. The US PPE supply chain has minimal ability to rapidly surge production, resulting in challenges to meeting large unexpected increases in demand that might occur during a public health emergency. Additionally, a significant proportion of the supply chain is produced off-shore and might not be available to the US market during an emergency because of export restrictions or nationalization of manufacturing facilities. Efforts to increase supplies during previous public health emergencies have been challenging. During the 2009 H1N1 influenza pandemic and the 2014 Ebola virus epidemic, the commercial supply chain of pharmaceutical and healthcare products quickly became critical response components. This article reviews lessons learned from these responses from a PPE supply chain and systems perspective and examines ways to improve PPE readiness for future responses.

Assessment of half-mask elastomeric respirator and powered air-purifying respirator reprocessing for an influenza pandemic

BACKGROUND

Health care facilities are considering the use of reusable respiratory protective devices (RPDs) to mitigate a potential N95 filtering facepiece respirator shortage caused by an influenza pandemic. US regulators are also considering stockpiling reusable RPDs for pandemic preparedness, but limited data exist on the effectiveness of cleaning and disinfection of these devices. This study defines reprocessing protocols and evaluates their effectiveness against a pandemic influenza strain in a laboratory setting.

METHODS

Five half-mask elastomeric respirator models and 3 powered air-purifying respirator models were contaminated with influenza virus and artificial skin oil on multiple surfaces. RPDs were then manually treated with 1 of 2 methods: cleaned or cleaned and disinfected. Presence of viable influenza was determined via swab sampling and a median tissue culture infectious dose assay.

RESULTS

Across 41 RPD surfaces, a mean log reduction in viable influenza of 4.54 ± 0.97 log₁₀ median tissue culture infectious dose was achieved for all treated surfaces, which included both cleaned and cleaned and disinfected surfaces.

CONCLUSIONS

The methods defined as part of this study are effective for eliminating viable influenza in the presence of artificial skin oil on most of the RPD surfaces tested. Material type and RPD design should be considered when implementing RPD reprocessing protocols.

Prevalence of Respiratory Protective Devices in U.S. Health Care Facilities: Implications for Emergency Preparedness

An online questionnaire was developed to explore respiratory protective device (RPD) prevalence in U.S. health care facilities. The survey was distributed to professional nursing society members in 2014 and again in 2015 receiving 322 and 232 participant responses, respectively. The purpose of this study was to explore if the emergency preparedness climate associated with Ebola virus disease changed the landscape of RPD use and awareness. Comparing response percentages from the two sampling time frames using bivariate analysis, no significant changes were found in types of RPDs used in health care settings. N95 filtering facepiece respirators continue to be the most prevalent RPD used in health care facilities, but powered air-purifying respirators are also popular, with regional use highest in the West and Midwest. Understanding RPD use prevalence could ensure that health care workers receive appropriate device trainings as well as improve supply matching for emergency RPD stockpiling.