Considerations for recommending extended use and limited reuse of filtering facepiece respirators in health care settings

Protective face mask: an effective weapon against SARS-CoV-2 with controlled environmental pollution

Masks are face coverings that give protection from infectious agents, airborne pathogens, bacteria, viruses, surgical fog, dust, and other chemical hazards by acting as a barrier between the wearer and the environment. In the COVID-19 pandemic, this major personal protective equipment's became essential part of our daily life. The aim of this review is to analyze and discuss the different types of masks with their pros and cons, manufacturing procedures, evaluation criteria, and application with some of the sterilization process for reuse and smart mask. The review used a thorough examination of the literature to analyze the preventive effects of surgical, N95, smart mask, and potential environmental damage from those masks. Several studies and evidence were also examined to understand the efficiency of different mask on different environment. N95 respirators are capable of filtering out non-oil-based 95% air-born particles, and surgical masks act as a protective barrier between the wearer and the environment. The application of spoon bond and melt blown techniques in the fabrication process of those masks improves their protective nature and makes them lightweight and comfortable. But the high demand and low supply forced users to reuse and extend their use after sterilizations, even though those masks are recommended to be used once. Universal masking in the SARS-COV-2 pandemic increased the chance of environmental pollution, so the application of smart masks became essential because of their high protection power and self-sterilizing and reusing capabilities.

Reusable and self-sterilization mask for real-time personal protection based on sunlight-driven photocatalytic reaction

Personal protective masks play critical role in preventing the disease epidemic and resisting pathogenic bacterial infestation. However, large quantities of masks were disposed during COVID-19 epidemic, which caused environmental problem and huge economic burden. Herein, we developed reusable masks with inherent antimicrobial and self-cleaning features under solar irradiation. With spun-bonded nonwoven fabrics (SNF) layer as substrate, copper sulfide@polydopamine nanoparticles are deposited on SNF layer (CuS@PDANPs-SNF), which presents excellent photocatalytic activity. Under solar irradiation, CuS@PDANPs produce abundant of singly linear oxygen (1O2), which inactivates pathogenic bacteria with high efficiency over 99%. Interestingly, CuS@PDANPs-SNF cannot cause high temperature to bring any uncomfortable to the person, which is suitable for human to wear in daily life. Such design effectively protect person from the transmission of viral aerosol. Meanwhile, CuS@PDANPs-SNF masks are reusable and still maintain robust bactericidal ability after washing. The sunlight-mediated self-sterilization at low temperature endows CuS@PDANPs-SNF masks as powerful personal protective equipment for daily protection, which also provides an instructive way for reducing the environmental impact.

Which alternative well-fit masks can be used in medical procedures?

BACKGROUND

During the COVID-19 pandemic, the WHO and CDC recommended that healthcare personnel (HCPs) performing non-aerosol-generating procedures (AGPs) don a properly fitted mask. We aimed to evaluate the fit factors (FFs) of eight alternative well-fit masks (AWMs) used by Thai HCPs.

METHODS

This comparative descriptive study was conducted on 33 HCPs between October and November 2022, categorized into three facial sizes: small, medium, and large. Each participant wore eight types of AWMs in random order: medical mask under adjustable ear-loop (AEL)-KF94 (MK), medical mask under AEL-KN95 with a hook (MN), medical mask under fabric mask (MF), AEL- KF94 (KF94), AEL-KF94 under fabric masks (KF), AEL-KF94 with a hook (KF94H), AEL-KN95 with a hook (KN95), and AEL-KN95 with a hook under fabric mask (NF). FFs were measured using a quantitative fit test.

RESULTS

The respective number of HCPs wearing small, medium, and large was 12, 12, and 9, and the mean±SD of face width and length was 132.98 ± 10.49 and 114.92 ± 10.10 mm. The highest respective median of FF was KN95 = 200, NF= 200, MN= 185, and KF94H = 171, and the respective passing fit-test rate was 97%, 84.8%, 63.6%, and 60.6%. There was no difference in FFs between the N95 and KN95 (p=0.72), the N95 and NF (p=0.202), and the three face sizes. Moreover, KF94H pass rates were significantly higher for females compared to males (OR = 13.3; p = 0.001) and for small facial sizes compared to either medium or large sizes (OR = 14.7; p = 0.009).

CONCLUSION

The AEL-KN95 with hook and sponge at the nosepiece is an effective respirator for use by HCPs in non-AGPs, as the FF and fit test pass rates were comparable to those of N95, and there were no differences in FFs between facial sizes. However, the female who had a small face size may use a KF94H as an alternative PPE.

Incidence of Fit Test Failure During N95 Respirator Reuse and Extended Use

Importance

The COVID-19 pandemic resulted in a widespread acute shortage of N95 respirators, prompting the Centers for Disease Control and Prevention to develop guidelines for extended use and limited reuse of N95s for health care workers (HCWs). While HCWs followed these guidelines to conserve N95s, evidence from clinical settings regarding the safety of reuse and extended use is limited.

Objective

To measure the incidence of fit test failure during N95 reuse and compare the incidence between N95 types.

Design, Setting, and Participants

This prospective cohort study, conducted from April 2, 2021, to July 15, 2022, at 6 US emergency departments (EDs), included HCWs who practiced N95 reuse for more than half of their clinical shift. Those who were unwilling to wear an N95 for most of their shift, repeatedly failed baseline fit testing, were pregnant, or had facial hair or jewelry that interfered with the N95 face seal were excluded.

Exposures

Wearing the same N95 for more than half of each clinical shift and for up to 5 consecutive shifts. Participants chose an N95 model available at their institution; models were categorized into 3 types: dome (3M 1860R, 1860S, and 8210), trifold (3M 1870+ and 9205+), and duckbill (Halyard 46727, 46767, and 46827). Participants underwent 2 rounds of testing using a different mask of the same type for each round.

Main Outcomes and Measures

The primary outcome was Occupational Safety and Health Administration-approved qualitative fit test failure. Trained coordinators conducted fit tests after clinical shifts and recorded pass or fail based on participants tasting a bitter solution.

Results

A total of 412 HCWs and 824 N95s were fit tested at baseline; 21 N95s (2.5%) were withdrawn. Participants' median age was 34.5 years (IQR, 29.5-41.8 years); 252 (61.2%) were female, and 205 (49.8%) were physicians. The overall cumulative incidence of fit failure after 1 shift was 38.7% (95% CI, 35.4%-42.1%), which differed by N95 type: dome, 25.8% (95% CI, 21.2%-30.6%); duckbill, 28.3% (95% CI, 22.2%-34.7%); and trifold, 61.3% (95% CI, 55.3%-67.3%). The risk of fit failure was significantly higher for trifold than dome N95s (adjusted hazard ratio, 1.75; 95% CI, 1.46-2.10).

Conclusions and Relevance

In this cohort study of ED HCWs practicing N95 reuse, fit failure occurred in 38.7% of masks after 1 shift. Trifold N95s had higher incidence of fit failure compared with dome N95s. These results may inform pandemic preparedness, specifically policies related to N95 selection and reuse practices.

Prospective analysis of the physiological changes caused by prolonged use of N95-type masks

INTRODUCTION

The clinical and physiological effects of long-duration use of N95-type masks without ventilation valves, on health-care workers during the coronavirus disease-2019 (COVID-19) pandemic, were evaluated.

METHODS

All volunteering personnel working in operating theater or intensive care unit, using nonventilated N95 type respiratory masks, minimum for a 2-h noninterrupted duration were observed. The partial oxygen saturation (SpO2) and heart rate (HR) were recorded before wearing the N95 mask and at 1st and 2nd h. Volunteers were then questioned for any symptoms.

RESULTS

A total of 210 measurements were completed in 42 (24 males and 18 females) eligible volunteers, each having 5 measurements, on different days. The median age was 32.7. Premask, 1st h, and 2nd h median values for SpO2 were 99%, 97%, and 96%, respectively (P < 0.001). The median HR was 75 premask, 79 at 1st h, and 84/min at 2nd h (P < 0.001). A significant difference between all three consecutive measurements of HR was achieved. Statistical difference was only reached between premask and other SpO2 measurements (1st and 2nd h). Complaints seen in the group were head ache (36%), shortness of breath (27%), palpitation (18%), and nausea feeling (2%). Two individuals took off their masks to breathe, on 87th and 105th min, respectively.

CONCLUSIONS

Long duration (>1 h) use of N95-type masks causes a significant reduction in SpO2 measurements and increase in HR. Despite being an essential personal protective equipment in COVID-19 pandemic, it should be used with short intermittent time periods in health-care providers with known heart disease, pulmonary insufficiency, or psychiatric disorders.

Effect of UV-C germicidal irradiation (UVGI) on the structural integrity of N95 and KN95 respirators

This study focuses on reprocessing a group of filtering facepiece respirators (FFR) using ultraviolet germicidal irradiation (UVGI). The aim is to explore the possibility of disinfecting selected KN95 FFRs, in comparison with the N95 FFRs, and assess their viability for reusage. For this purpose, five models of unused N95 and KN95 FFR models obtained from the hospital were exposed to UV-C light using a customized UVGI chamber. The material integrity of treated FFRs was examined in terms of particle penetration and strap tension. The surface morphology of all models is inspected to determine the visible changes of each FFR upon exposure to 1-100 cycles (1 cycle is equivalent to 1 J/cm² UV dose). The penetration test results indicate that the physical properties of the KN95 and N95 FFRs remain within permissible limits despite being reprocessed by up to 100 cycles (100 J/cm²). Using a microscope, the physical observations also reveal that no visible damage can be seen even after 100 J/cm² exposure. Apart from the filter bodies, the tension of each strap was also found to not be significantly affected by UV radiation by at least 10 disinfection cycles (10 J/cm²). This confirms that KN95, as well as N95 FFRs, can be subjected to UV treatment as a means of disinfection.

Evaluating fomite risk of brown paper bags storing personal protective equipment exposed to SARS-CoV-2: A quasi-experimental study

INTRODUCTION

Literature is lacking on the safety of storing contaminated PPE in paper bags for reuse, potentially increasing exposure to frontline healthcare workers (HCW) and patients. The aim of this study is to evaluate the effectiveness of paper bags as a barrier for fomite transmission of SARS-CoV-2 by storing face masks, respirators, and face shields.

METHODS

This quasi-experimental study evaluated the presence of SARS-CoV-2 on the interior and exterior surfaces of paper bags containing PPE that had aerosolized exposures in clinical and simulated settings. Between May and October 2020, 30 unique PPE items were collected from COVID-19 units at two urban hospitals. Exposed PPE, worn by either an infected patient or HCW during a SARS-CoV-2 aerosolizing event, were placed into an unused paper bag. Samples were tested at 30-minute and 12-hour intervals.

RESULTS

A total of 177 swabs were processed from 30 PPE samples. We found a 6.8% positivity rate among all samples across both collection sites. Highest positivity rates were associated with ventilator disconnection and exposure to respiratory droplets from coughing. Positivity rates differed between hospital units. Total positivity rates were similar between 30-minute (6.7%) and 12-hour (6.9%) sample testing time intervals. Control samples exposed to inactivated SARS-CoV-2 droplets had higher total viral counts than samples exposed to nebulized aerosols.

CONCLUSIONS

Data suggests paper bags are not a significant fomite risk for SARS-CoV-2 transmission. However, controls demonstrated a risk with droplet exposure. Data can inform guidelines for storing and re-using PPE in situations of limited supplies during future pandemics.

Perioperative provider safety in the pandemic: Development, implementation and evaluation of an adjunct COVID-19 Surgical Patient Checklist

The COVID-19 pandemic has strained surgical systems worldwide and placed healthcare providers at risk in their workplace. To protect surgical care providers caring for patients with COVID-19, in May 2020 we developed a COVID-19 Surgical Patient Checklist (C19 SPC), including online training materials, to accompany the World Health Organization Surgical Safety Checklist. In October 2020, an online survey was conducted via partner and social media networks to understand perioperative clinicians’ intraoperative practice and perceptions of safety while caring for COVID-19 positive patients and gain feedback on the utility of C19 SPC. Descriptive statistics were used to characterise responses by World Bank income classification. Qualitative analysis was performed to describe respondents' perceptions of C19 SPC and recommended modifications. Respondents included 539 perioperative clinicians from 63 countries. One-third of respondents reported feeling unsafe in their workplace due to COVID-19 with significantly higher proportions in low (39.8%) and lower-middle (33.9%) than higher income countries (15.6%). The most cited concern was the risk of COVID-19 transmission to self, colleagues and family. A large proportion of respondents (65.3%) reported that they had not used C19 SPC, yet 83.8% of these respondents felt it would be useful. Of those who reported that they had used C19 SPC, 62.0% stated feeling safer in the workplace because of its use. Based on survey results, modifications were incorporated into a subsequent version. Our survey findings suggest that perioperative clinicians report feeling unsafe at work during the COVID-19 pandemic. In addition, adjunct tools such as the C19 SPC can help to improve perceived safety.

The Dangers of Reused Personal Protective Equipment: Healthcare Workers and Workstation Contamination

Background

Personal protective equipment (PPE) is essential to protect healthcare workers (HCWs). The practice of reusing PPE poses high levels of risk for accidental contamination by HCWs. Scarce medical literature compares practical means or methods for safe reuse of PPE while actively caring for patients.

Methods

In this study, observations were made of 28 experienced clinical participants performing five donning and doffing encounters while performing simulated full evaluations of patients with coronavirus disease 2019. Participants' N95 respirators were coated with a fluorescent dye to evaluate any accidental fomite transfer that occurred during PPE donning and doffing. Participants were evaluated using blacklight after each doffing encounter to evaluate new contamination sites, and were assessed for the cumulative surface area that occurred due to PPE doffing. Additionally, participants' workstations were evaluated for contamination.

Results

All participants experienced some contamination on their upper extremities, neck and face. The highest cumulative area of fomite transfer risk was associated with the hook and paper bag storage methods, and the least contamination occurred with the tabletop storage method. Storing a reused N95 respirator on a tabletop was found to be a safer alternative than the current recommendation of the US Centers for Disease Control and Prevention to use a paper bag for storage. All participants donning and doffing PPE were contaminated.

Conclusion

PPE reusage practices pose an unacceptably high level of risk of accidental cross-infection contamination to healthcare workers. The current design of PPE requires complete redesign with improved engineering and usability to protect healthcare workers.

Always-on photocatalytic antibacterial facemask with mini UV-LED array

The facemask is a device to protect yourself and others against pandemics, such as coronavirus disease 2019 (COVID-19), and adding a functional filter to the facemask could offer extra protection against infectious microbes (such as bacteria and viruses) to the wearer. Here, we designed and fabricated an always-on photocatalytic antibacterial facemask, which comprised a reusable polypropylene filter layer coated with the photocatalytic laminated ZnO/TiO₂ bilayer and a separate UV-LEDs layer to supply UV whenever necessary. The fabricated photocatalytic filter was able to be directly inserted into the reusable facemask together with the UV-LEDs layer. This facemask could be used repeatedly and sustainably anytime and anywhere regardless of solar illumination. The photocatalytic filter exhibited an excellent photocatalytic antibacterial effect likely due to recombination suppression of electrons and holes of ZnO/TiO₂ bilayer and wetting transition from hydrophilic to superhydrophilic state on the surface of the filter. Thanks to the kirigami pattern in both photocatalytic filter and UV-LEDs layer, full-face covering, breathability, flexibility, and the snug fit are believed to be improved. Although further in-depth studies are still needed and there is a long way to go, we expect our design idea on the facemask to be considered in various fields.

Infection Prevention and Control of Severe Acute Respiratory Syndrome Coronavirus 2 in Health Care Settings

The authors describe infection prevention and control approaches to severe acute respiratory syndrome coronavirus 2 in the health care setting, including a review of the chain of transmission and the hierarchy of controls, which are cornerstones of infection control and prevention. The authors also discuss lessons learned from nosocomial transmission events.

Comparison of filtration efficiency and respiratory resistance of COVID-19 protective masks by multi-national standards

Background

Face masks from worldwide satisfy different standards during the COVID-19 pandemic, which led to the public misunderstanding of the concepts.

Methods

We systematically evaluated the quality of face masks provided by different companies according to multi-national standards, including EN 149-2001+A1: 2009, GB 2626-2019 and NIOSH 42 CFR Part 84-2019, focusing particularly on the particulate filtration efficiency (PFE) and respiratory resistance performance.

Results

Three types of masks (planar, folding and cup type masks) were measured based on different standard protocols. The results indicated that the PFE of the mask decreased in sequence of folding mask ≈ cup type mask > planar mask. The respiratory resistance of the masks ranked as follows: cup type mask > folding mask> planar mask. Overall, when PFE was used as the quality indicator, all the masks have a higher chance of meeting criteria of the EN149-2001+A1:2009, followed by the stricter standard set by the GB2626-2019 and NIOSH 42 CFR Part84-2019. Conversely, the respiratory resistance of the masks fulfilled the highest requirement of the EN149-2001+A1:2009 standard, while it is easier to satisfied the standard of GB 2626-2019 and NIOSH 42 CFR Part 84-2019.

Conclusions

We believe that our study provides effective guidance for customers worldwide to choose proper face masks under different epidemic situations.

One for Everyone: A Study of User Satisfaction Among Health-Care Providers Regarding Extended Use of N95 Masks During the COVID-19 Pandemic

OBJECTIVE

This study was conducted to assess the feasibility of extended use of N95 masks in our hospital during the coronavirus disease 2019 (COVID-19) pandemic. We also studied the use pattern, user satisfaction, and issues faced during extended use of the mask.

METHODS

This cross-sectional study was conducted among health-care providers in a large tertiary care teaching hospital in northern India from April 1 to May 31, 2020. A list was prepared from the institute's register, and participants were chosen by random sampling. The data collected from the physical forms were transferred to excel sheets.

RESULTS

A total of 1121 responses were received. The most common problem stated with reuse of N95 masks was loss of fit followed by damage to the slings, highlighted by 44.6% and 44.4% of the participants, respectively. A total of 476 (42.5%) participants responded that they would prefer "cup-shaped N95 mask with respirator". The median scores regarding the satisfaction with the quality of masks and their fit was also 4 each.

CONCLUSIONS

It was concluded that the extended use of N95 masks was acceptable, with more than 96% of the participants using these masks.

Early Experiences Designing a Scalable COVID-19 Reusable Elastomeric Respirator

The COVID-19 pandemic created an unprecedented shortage of personal protective equipment (PPE) for healthcare workers - especially respirators. In response to a lack of commercial respirator equipment, a multidisciplinary prototyping hackathon was held and the key components required to develop an inexpensive, scalable "COVID-19 Reusable Elastomeric Respirator" (RER-19) were identified. Available hospital supplies were assessed based on their published technical specifications to meet each of the key component requirements. The fully assembled prototype was then validated through user testing, and volunteers underwent standard fit testing with cardiopulmonary monitoring while wearing the RER-19 in a small pilot study. Multiple social media platforms were then used to disseminate educational information on respirator assembly, use, and maintenance. Here we present our institution's initial experience with prototyping to meet a specific healthcare challenge, in combination with prompt dissemination of information to educate and empower healthcare workers in the face of a critical PPE shortage during an unprecedented and evolving pandemic.

Decontamination of High-Efficiency Mask Filters From Respiratory Pathogens Including SARS-CoV-2 by Non-thermal Plasma

The current pandemic resulted in a rapidly increasing demand for personal protective equipment (PPE) initially leading to severe shortages of these items. Hence, during an unexpected and fast virus spread, the possibility of reusing highly efficient protective equipment could provide a viable solution for keeping both healthcare professionals and the general public equipped and protected. This requires an efficient decontamination technique that preserves functionality of the sensitive materials used for PPE production. Non-thermal plasma (NTP) is a decontamination technique with documented efficiency against select bacterial and fungal pathogens combined with low damage to exposed materials. We have investigated NTP for decontamination of high-efficiency P3 R filters from viral respiratory pathogens in comparison to other commonly used techniques. We show that NTP treatment completely inactivates SARS-CoV-2 and three other common human respiratory viruses including Influenza A, Rhinovirus and Adenovirus, revealing an efficiency comparable to 90°C dry heat or UVC light. Unlike some of the tested techniques (e.g., autoclaving), NTP neither influenced the filtering efficiency nor the microstructure of the filter. We demonstrate that NTP is a powerful and economic technology for efficient decontamination of protective filters and other sensitive materials from different respiratory pathogens.

Measures against COVID-19 pandemic - a single tertiary center experience

This paper reports the measures taken to manage the impact of the COVID-19 pandemic on O&G services in a tertiary referal centre and their outcomes. All the patients included in this study received inpatient treatment and underwent surgery between March 10 2020 and end of June 2020, including obstetric or gynaecologic cases combined. Data including age, diagnosis, operation, duration of preoperative and postoperative hospital stay, COVID-19 status were recorded. COVID-19 status of the patients was diagnosed with a nasopharyngeal swab test. Thirty-seven (20%) of 177 operations were performed because of gynaecologic reasons. The rest of them were caesarean sections (C/S). In gynaecologic cases, 22 (59%) of 37 were emergent operations, nine (24%) cases were oncologic and six (16%) cases were elective gynaecological surgeries. On the other hand, 43 (30%) of 140 patients, who underwent caesarean sections, were urgent surgeries. The rest were elective and planned caesarean sections. Only five patients (2.8%) who had undergone caesarean sections were tested positive for COVID-19. No COVID-19 transmission to staff was recorded in this period. Measures against the COVID-19 pandemic must be multidisciplinary and is crucial to prevent the spread of the disease to staff in close contact.Impact StatementWhat is already known on this subject? COVID-19 pandemic has been a crucial health problem worldwide. Healthcare workers work intensely to protect people from the pandemic. It is especially important to protect healthcare professionals and hospitalized patients from virus transmission. Therefore, utilization of personal protective equipment such as masks, gloves and goggles is obligatory, and hygiene rules such as sanitization of hands are strictly followed.What the results of this study add? This study adds the experience and success of a tertiary centre regarding the measure against COVID-19 to the literature. No viral transmission was detected to healthcare workers and other patients from COVID-19 patients. Hence, measures that mentioned in the present study should be an example to other centres for protection against pandemic.What the implications are of these findings for clinical practice and/or further research? As mentioned above, measures that are explained in the present study should be an example to other centres for protection against the pandemic. Further larger size clinical studies are needed to prove the beneficial effect of the measures that still used against pandemic.

Impact on the fitness of N95 masks with extended use/limited reuse and dry heat decontamination

Substandard use of N95 masks, sometimes combined with dry heat decontamination, lacks safety data. We evaluated the impact of these practices on the fitness of N95 masks. This is a non-human subject research conducted from July to October 2020. 155 masks were used by 12 healthcare workers during 10-hour shifts. Masks were collected at the end of the shift and if the number of donnings/doffings was less than five ('modified extended use', ME) or whenever this number reached five ('limited reuse', LR), per the recommendation of the Centers for Disease Control and Prevention. Masks that passed an Occupational Safety and Health Administration qualitative fit test underwent a cycle (30 min, 75°C) of dry heat decontamination. After use, 84% (95% CI 77% to 90%) of the masks fit the users, 85% (95% CI 73% to 93%) in ME and 83% (95% CI 73% to 90%) in LR. After dry heat, 86% of the fitted masks (95% CI 78% to 91%) still fit, 93% (95% CI 80% to 98%) in ME and 82% (95% CI 70% to 89%) in LR. If a fit test was not done before decontamination, 72% (95% CI 64% to 79%) of the masks would fit, 79% (95% CI 66% to 88%) in ME and 68% (95% CI 57% to 77%) in LR. Common substandard use preserves fitness of N95 masks up to 85%. One cycle of dry heat decontamination preserves fitness of N95 masks up to 93% when donned/doffed less than five times and fitness is ensured before decontamination. If a fit test is not performed beforehand, dry heat decontamination cannot preserve the fitness of used N95 masks above 80%.

Persistence of SARS-Co-V-2 on N95 filtering facepiece respirators: implications for reuse

In response to the shortage of N95 filtering facepiece respirators for healthcare workers during the COVID-19 pandemic, the Centers for Disease Control and Prevention issued guidance for extended use and limited reuse of N95 FFRs to conserve supply. Previously worn N95 filtering facepiece respirators can serve as a source of pathogens, which can be transferred to the wearer while doffing and donning a respirator when practicing reuse. When practicing limited filtering facepiece respirators reuse, to reduce the risk of self-contamination, the Centers for Disease Control and Prevention recommends storing filtering facepiece respirators for five days between uses to allow for the decay of viable pathogens including SARS-CoV-2. This study assesses the persistence of the SARS-CoV-2 strain USA-WA1/2020 on N95 filtering facepiece respirators under controlled storage conditions for up to 5 days to inform the Centers for Disease Control and Prevention guidance. Coupons excised from six N95 filtering facepiece respirator models and glass slide coverslips were inoculated with the virus in a defined culture medium and in human saliva and stored at 20 °C and 20%, 45%, and 75% relative humidity. Statistically significant differences in SARS-CoV-2 half-lives were measured among the tested humidity levels with half-lives decreasing from an average of approximately 30 hr at 20% relative humidity to approximately 2 hr at 75% relative humidity. Significant differences in virus half-lives were also observed between the culture medium and saliva suspension media at 20% and 45% relative humidity with half lives up to 2.9 times greater when the virus was suspended in cell culture medium. The 5-day storage strategy, assessed in this study, resulted in a minimum of 93.4% reduction in viable virus for the most challenging condition (20% relative humidity, cell culture medium) and exceeding 99% reduction in virus at all other conditions.

A simple and cheap aerosol penetrometer for filter testing using an electronic cigarette

Background: During the coronavirus disease 2019 (COVID-19) pandemic face masks grew in importance as their use by the general population was recommended by health officials in order to minimize the risk of infection and prevent further spread of the virus. To ensure health protection of medical personnel and other system relevant staff, it is of considerable interest to quickly test if a certain lot of filtering facepiece masks meets the requirements or if the penetration changes under different conditions. As certified penetrometers are rather expensive and were difficult to obtain during the COVID-19 pandemic, we describe two quite simple and cheap methods to quickly test the filter penetration based on an electronic cigarette. Methods: The first method uses a precision scale, the second method uses a light scattering detector to measure the filter penetration. To make sure these two methods yield reliable results, both were tested with freshly cut filter samples covering the range of approx. 2 % to 60 % filter penetration and compared to the results of a certified penetrometer. Results: The comparison of the two methods with the certified penetrometer showed a good correlation and therefore allow a quick and rather reliable estimation of the penetration. Conclusions: Several examples about the use of faulty masks and the resulting health risks show that simple, fast, cheap and broadly available methods for filter characterization might be useful in these days.

[Limited Reuse and Extended Use of Filtering Facepiece Respirators]

Objetivo

Los equipos de protección individual (EPI), y dentro de ellos las mascarillas, son fundamentales en una pandemia como la del COVID-19, que ha requerido, en muchas ocasiones, de reutilización de material debido a su escasez. El objetivo de esta revisión es sintetizar la evidencia disponible sobre la reutilización y uso extendido de las mascarillas de media y alta filtración.

Método

Revisión exploratoria. Búsqueda a través de lenguaje natural en PubMed y Centros, Agencias y Organizaciones para el Control de Enfermedades. Se limitó a artículos publicados entre 2010-2020 en inglés y en español.

Resultados

Se localizaron 83 artículos, seleccionándose 14, más cinco recomendaciones. Los temas abordados se clasifican en siete apartados: Caducidad, uso extendido y reutilización de mascarillas, técnica de manipulación, sellado, efectos físicos psicológicos y cumplimentación, contaminación y descontaminación de mascarillas.

Conclusiones

La reutilización de las mascarillas no está recomendada por los organismos oficiales ni los fabricantes, sólo se acepta en casos extraordinarios, como las pandemias. Los estudios se caracterizan por contar con muestras pequeñas, usan diferentes modelos de mascarillas ajustando su recomendación al modelo.

[Analysis of the materials for the manufacture of masks: The challenge of facing the shortage of personal protective equipment]

The main element of personal protective equipment against the SARS-CoV-2 pandemic are masks, which protect against droplets and aerosols that can remain suspended in the air. The objective of this study is to summarize the existing evidence on the filtration of different materials for the manufacture of masks. A scoping review or exploratory review has been carried out in the PubMEd and Scopus databases, using the terms "respirator", "mask", "facemask", "material", and "tissue", combined with Boolean operators. The results show some of the materials used for the manufacture of masks, both surgical masks and medium-high filtration masks, as well as materials used for the manufacture of household masks. As a conclusion, it is necessary to know the characteristics of the different materials as well as their properties to guarantee an adequate use according to the specific needs in each context, being fundamental the application of particle filtration systems as well as support materials that comply with current recommendations.

Availability and use of personal protective equipment and satisfaction of healthcare professionals during COVID-19 pandemic in Addis Ababa, Ethiopia

BACKGROUND

Healthcare professionals (HCPs) are at the frontline in the fight against COVID-19 and are at an increased risk of becoming infected with coronavirus. Risk of infection can be minimized by use of proper personal protective equipment (PPE). The aim of this study was to assess the availability and use of PPE, and satisfaction of HCPs with PPE in six public hospitals in Addis Ababa, Ethiopia.

METHODS

A cross-sectional study was conducted among 1134 HCPs in June 2020. A systematic random sampling and consecutive sampling techniques were used to select the study participants. Data were collected using a self-administered questionnaire. Descriptive statistics were used to describe the data and Chi-square test was used to assess the association between the groups. Bivariate and multivariable logistic regression models were used to assess factors associated with satisfaction of healthcare workers.

RESULTS

The mean (±SD) age of the participants was 30.26 ± 6.43 year and 52.6% were females. Nurses constituted about 40% of the overall sample, followed by physicians (22.2%), interns (10.8%), midwives (10.3%) and others (16.7%). The majority (77%) of the HCPs reported that their hospital did not have adequate PPE. A critical shortage of N95 respirators was particularly reported, it only increased from 13 to 24% before and during COVID-19, respectively. The use of N95 increased from 9 to 21% before and during COVID-19, respectively. Almost 72% of the respondents were dissatisfied with the availability and use of PPE in their hospital. The independent predictors of the respondents' satisfaction level about PPE were healthcare workers who reported that PPE was adequately available in the hospital (adjusted OR = 7.65, 95% CI:5.09-11.51), and preparedness to provide care to COVID-19 cases (adjusted OR = 2.07, 95% CI:1.42-3.03).

CONCLUSIONS

A critical shortage of appropriate PPE and high level of dissatisfaction with the availability and use of PPE were identified. Therefore, urgent efforts are needed to adequately supply the healthcare facilities with appropriate PPE to alleviate the challenges.

Photocatalytic Rejuvenation Enabled Self-Sanitizing, Reusable, and Biodegradable Masks against COVID-19

Personal protective equipment (PPE) has been highly recommended by the U.S. Centers for Disease Control and Prevention for self-protection during the disastrous SARS-CoV-2 (COVID-19) pandemic. Nevertheless, massive utilization of PPE encounters significant challenges in recycling and sterilizing the used masks. To tackle the associated plastic pollution of used masks, in this work, we designed a reusable, biodegradable, and antibacterial mask. The mask was fabricated by the electrospinning of polyvinyl alcohol (PVA), poly(ethylene oxide) (PEO), and cellulose nanofiber (CNF), followed by esterification and the deposition of a nitrogen-doped TiO2 (N-TiO2) and TiO2 mixture. The fabricated mask containing photocatalytic N-TiO2/TiO2 reached 100% bacteria disinfection under either 0.1 sun simulation (200-2500 nm, 106 W m-2) or natural sunlight for only 10 min. Thus, the used mask can be rejuvenated through light irradiation and reused, which represents one of the handiest technologies for handling used masks. Furthermore, intermolecular interactions between PVA, PEO, and CNF enhanced the electrospinnability and mechanical performance of the resultant mask, which possesses a 10-fold elastic modulus and 2-fold tensile strength higher than a commercial single-use mask. The porous structures of electrospun nanofibers along with strong electrostatic attraction enabled breathability (83.4 L min-1 of air flow rate) and superior particle filterability (98.7%). The prepared mask also had excellent cycling performance, wearability, and stable filtration efficiency even after 120 min wearing. Therefore, this mask could be a great alternative to current masks to address the urgent need for a sustainable, reusable, environmentally friendly, and efficient PPE under the ongoing COVID-19 contagion.

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.

In-House Filtration Efficiency Assessment of Vapor Hydrogen Peroxide Decontaminated Filtering Facepiece Respirators (FFRs)

To cope with the shortage of filtering facepiece respirators (FFRs) caused by the coronavirus disease (COVID-19), healthcare institutions have been forced to reuse FFRs using different decontamination methods, including vapor hydrogen peroxide (VHP). However, most healthcare institutions still struggle with evaluating the effect of VHP on filtration efficiency (FE) of the decontaminated FFRs. We developed a low-cost in-house FE assessment using a novel 3D-printed air duct. Furthermore, we assessed the FE of seven types of FFRs. Following 10 VHP cycles, we evaluated the FE of KN95 and 3M-N95 masks. The 3M-N95 and Benehal-N95 masks showed significant lower FE (80.4-91.8%) at fine particle sizes (0.3-1 µm) compared to other FFRs (FE ≥ 98.1%, p < 0.05). Following 10 VHP cycles, the FE of KN95 masks was almost stable (FE stability > 99.1%) for all particle sizes, while 3M-N95 masks were stable only at 2 and 5 µm (FE stability > 98.0%). Statistically, FE stability of 3M-N95 masks at 0.3, 0.5, and 0.7 µm was significantly lower (p ≤ 0.006) than 2 and 5 µm. The in-house FE assessment may be used as an emergency procedure to validate the decontaminated FFRs, as well as a screening option for production control of FFRs. Following VHP cycles, both masks showed high stability at 5 µm, the size of the most suspected droplets implicated in COVID-19 transmission.

Reuse of face masks among adults in Hong Kong during the COVID-19 pandemic

Background

During the COVID-19 pandemic, over 99% of adults in Hong Kong use face masks in public. With the limited supply of face masks in the market and the uncertainty about the future development of COVID-19, reusing face masks is a legitimate way to reduce usage. Although this practice is not recommended, reusing face masks is common in Hong Kong. This study aimed to examine the practice of reusing face masks among adults in Hong Kong during the COVID-19 pandemic and its association with their health beliefs toward this health crisis.

Methods

A cross-sectional descriptive study was conducted. A quota sample of 1000 adults was recruited in Hong Kong in April 2020. Guided by the Health Belief Model, the subjects were invited to answer questions on their practice of reusing face masks and health beliefs toward COVID-19 through telephone interview. Their practice on reuse, storage, and decontamination of used face masks were summarized by descriptive statistics. The difference in health beliefs between the subjects who reused and did not reuse face masks was examined by conducting an independent t test. The association between health beliefs and reuse of face masks was determined by conducting a logistic regression analysis.

Results

One-third (n = 345, 35.4%) of the subjects reused face masks in an average of 2.5 days. Among them, 207 subjects stored and 115 subjects decontaminated their used face masks by using various methods. The subjects who reused face masks significantly perceived having inadequate face masks (t = 3.905; p <  0.001). Having a higher level of perception of having inadequate face masks increased the likelihood of reusing face masks (OR = 0.784; CI 95%: 0.659–0.934; p = 0.006).

Conclusion

Despite having 90 face masks in stock, the adults who reused face masks significantly perceived that they had inadequate face masks. Concerted effort of health care professionals, community organizations, and the government will improve individuals’ practice in use of face masks and alleviate their actual and perceived feeling of having inadequate face masks, which lead them to reuse.

A virucidal face mask based on the reverse-flow reactor concept for thermal inactivation of SARS-CoV-2

While facial coverings reduce the spread of SARS-CoV-2 by viral filtration, masks capable of viral inactivation by heating can provide a complementary method to limit transmission. Inspired by reverse-flow chemical reactors, we introduce a new virucidal face mask concept driven by the oscillatory flow of human breath. The governing heat and mass transport equations are solved to evaluate virus and CO2 transport. Given limits imposed by the kinetics of SARS-CoV-2 thermal inactivation, human breath, safety, and comfort, heated masks may inactivate SARS-CoV-2 to medical-grade sterility. We detail one design, with a volume of 300 ml at 90°C that achieves a 3-log reduction in viral load with minimal impedance within the mask mesh, with partition coefficient around 2. This is the first quantitative analysis of virucidal thermal inactivation within a protective face mask, and addresses a pressing need for new approaches for personal protective equipment during a global pandemic.

Failure Rates During Reuse of Disposable N95 Masks in Clinical Practice in the Emergency Department

INTRODUCTION

The coronavirus 2019 pandemic caused a shortage of disposable N95 respirators, prompting healthcare entities to extend the use of these masks beyond their intended single-use manufacturer recommendation with a paucity of supporting research.

METHODS

We performed a prospective cohort study of ED healthcare workers (HCW) ("subjects") required to use respirators at an academic, Level I trauma center. Subjects had been previously fit tested and assigned an appropriately sized N95 mask per hospital protocol. Per study protocol, subjects were fit tested periodically throughout their shifts and on multiple shifts over the eight-week study period. Data points collected included the age of the mask, subjective assessment of mask seal quality, and fit test results. We analyzed the data using Fisher's exact test, and calculated odds ratios (OR) to determine the failure rate of disposable N95 masks following reuse.

RESULTS

A total of 130 HCWs underwent fit testing and 127 were included for analysis. Mask failure rate climbed after day 2 of use, with 33.3% of masks failing at day 3, 42.9% at day 4, and 50% at ≥ day 5. Categorizing the masks into those being used for two or fewer days vs those in use for three or more, failure was more common on day 3 of use or older compared to those in the first two days of use (41.8% vs 8.3%, P < 0.0001) with an OR of failure with an older mask of 7.9 (confidence interval [CI], 2.8-22.3). The healthcare workers' assessment of poor seal was 33.3% sensitive (CI, 18.6-51.9) and 95.7% specific (CI, 88.8-98.6) for fit test failure.

CONCLUSION

Disposable N95 masks have significant failure rates following reuse in clinical practice. Healthcare personnel also performed poorly in assessing the integrity of the seal of their disposable respirators.

A Practical Approach to Filtering Facepiece Respirator Decontamination and Reuse: Ultraviolet Germicidal Irradiation

Purpose of review

Prior outbreaks of respiratory viruses have demonstrated the need for adequate personal protective equipment (PPE) for healthcare workers, particularly filtering facepiece respirators (FFR). Due to shortfalls of PPE during the SARS CoV-2 pandemic, the need for FFR decontamination and reuse (FFR-DR) strategies is paramount. This paper aims to discuss primary decontamination strategies, with an in-depth analysis of ultraviolet germicidal irradiation (UVGI), arriving at the decontamination strategy utilized at the Nebraska Medical Center (NMC).

Methods

Review of the primary literature in regard to FFR-DR as well as a synopsis of the current protocol for FFR-DR at NMC.

Recent findings

UVGI demonstrates effective decontamination of multiple pathogens-including several human respiratory viruses-while maintaining mask integrity and filtering capacity. UVGI was associated with degradation of strap integrity at higher doses than that utilized for decontamination or with reuse beyond 20 times.

Summary

UVGI effectively decontaminates N95 FFRs without significant reduction to fit or strap integrity and can be employed as a strategy for FFR-DR in times of emergency.

Nurses' preparedness and response to COVID-19

Introduction

Coronavirus disease is the most striking pandemic across the world that every country is addressing and talking about it now. Nurses deliver the highest level of functioning in the health care team. Nurses need to understand the COVID-19 preparedness and response process. Therefore, it becomes very important to assess a nurse's knowledge of preparedness and response to Corona Virus Disease (Covid-19).

Methods

The research approach was quantitative in nature by using the descriptive cross-sectional survey among nurses working under MOH Hospitals in Najran region, KSA. The sample participated in the survey was 594 and the tool used for the study was a modified questionnaire on Nurse's preparedness and response to COVID-19. The questionnaire contained five parts and the first part included basic information of the nurses and the second part was composed of yes or no questions assessing the nurse's Knowledge on COVID-19 preparedness and the third part composed of facility and response readiness to triage screening and the fourth part consist of nurses preparedness and readiness on COVID and fifth part composed of nurse's preparedness and readiness on peroneal protective equipment's and the study was approved by Institutional Review Board (IRB). Data was presented by using descriptive and inferential statistics.

Results

Our study results found that overall knowledge of COVID preparedness was adequate. However, the nurse's preparedness on personal protective equipment was moderate. Majority of respondents were Registered Nurses 587(98.9%)and most of the respondents were employed by the Ministry of Health 586(98.7%)and the nurse's knowledge of preparedness was 456(76.8%) and the facilities preparedness and response readiness was 549(92.4) and adequate supply of personal protective equipment (PPE) 519(87. 3%).

Conclusion

The findings of the study exhibit that nurses have an adequate level of knowledge towards the preparedness and response to coronavirus diseases.

Facing the Coronavirus Pandemic: An Integrated Continuing Education Program in Taiwan

This study aimed to identify knowledge gaps regarding coronavirus disease 2019 (COVID-19) and develop an integrated educational program for healthcare workers. First, we designed and validated ten multiple-choice questions to identify knowledge gaps among healthcare workers. Within one month of the online test and curriculum offering, 5533 staff had completed the test, with a completion rate of 84.97%. There were 2618 healthcare workers who answered the pre-test 100% correctly. Those who did not answer the pre-test 100% correctly took multiple tests after learning through the online teaching materials. Eventually, 5214 staff passed the test (pre-test or post-test with 100% correct answers). The result showed that all staff had a low correct rate for personal protective equipment (PPE) use recommendations. The Infection Control Center conducted training sessions for hospital staff on how to wear protective clothing. Information on the selection and use of PPE for infection prevention was provided, and participants were allowed time to practice and familiarize themselves with the correct way to wear PPE. Moreover, the Department of Education and Research continued updating the online learning materials based on the most important updated peer-reviewed published articles. The attending teaching physicians helped to search, translate, and take notes on articles in the local language (traditional Chinese) for other colleagues to read easily. We expect to increase learning opportunities for healthcare workers, even during uncertain times such as the current coronavirus pandemic through (1) the hospital-wide course announcements, (2) the continuous placement of test questions and learning files on the digital learning platform, (3) the placement of journal highlights in cloud folders, and (4) the use of the digital learning platform on mobile phones accessible outside the hospital.

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.

Elastomeric Half Mask Respirators: An Alternative to Disposable Respirators and a Solution to Shortages during Public Health Emergencies

During public health emergencies such as an influenza pandemic, disposable filtering facepiece respirator (FFR) shortages have a significant impact on the national response, affecting many types of workplaces that rely on respiratory protection. During the COVID-19 pandemic, severe FFR shortages led the CDC to publish strategies for optimizing the supply of N95 FFRs. These strategies included the extended use and limited reuse of FFRs, wearing decontaminated FFRs, wearing respirators that meet an international respirator standard, or wearing FFRs that were past their manufacturer-designated shelf life. An additional strategy to mitigate supply shortages that was highlighted during the COVID-19 pandemic was to wear reusable respirators, such as elastomeric half mask respirators (EHMRs), or powered air-purifying respirators, which can be cleaned, disinfected, and reused. A decade of nationwide initiatives to increase the utility of EHMRs in healthcare settings were realized during the COVID-19 pandemic as EHMRs became more well-known and were used in healthcare settings for respiratory protection. This expanded use of EHMRs led to an increase in federal procurement, research, guidance, and private sector research and development of innovative EHMR designs by manufacturers to respond to workers' needs for both respiratory protection and source control. This paper describes the role of reusable EHMRs before and during the COVID-19 pandemic, and reviews past and current research, to inform successful EHMR implementation in healthcare and first responder settings.

Decontamination and Reuse of N95 Filtering Facepiece Respirators: Where Do We Stand?

The coronavirus disease 2019 (COVID-19) pandemic created an extraordinary demand for N95 and similarly rated filtering facepiece respirators (FFR) that remains unmet due to limited stock, production constraints, and logistics. Interest in decontamination and reuse of FFR, a product class designed for single use in health care settings, has undergone a parallel surge due to shortages. A worthwhile decontamination method must provide effective inactivation of the targeted pathogen(s), and preserve particle filtration, mask fit, and safety for a subsequent user. This discussion reviews the background of the current shortage, classification, structure, and functional aspects of FFR, and potentially effective decontamination methods along with reference websites for those seeking updated information and guidance. The most promising techniques utilize heat, hydrogen peroxide, microwave-generated steam, or ultraviolet light. Many require special or repurposed equipment and a detailed operational roadmap specific to each setting. While limited, research is growing. There is significant variation between models with regard to the ability to withstand decontamination yet remain protective. The number of times an individual respirator can be reused is often limited by its ability to maintain a tight fit after multiple uses rather than by the decontamination method itself. There is no single solution for all settings; each individual or institution must choose according to their need, capability, and available resources. As the current pandemic is expected to continue for months to years, and the possibility of future airborne biologic threats persists, the need for plentiful, effective respiratory protection is stimulating research and innovation.

Pragmatic Recommendations for Safety while Caring for Hospitalized Patients with COVID-19 in Low- and Middle-Income Countries

Infection prevention and control measures to control the spread of COVID-19 are challenging to implement in many low- and middle-income countries (LMICs). This is compounded by the fact that most recommendations are based on evidence that mainly originates in high-income countries. There are often availability, affordability, and feasibility barriers to applying such recommendations in LMICs, and therefore, there is a need for developing recommendations that are achievable in LMICs. We used a modified version of the GRADE method to select important questions, searched the literature for relevant evidence, and formulated pragmatic recommendations for safety while caring for patients with COVID-19 in LMICs. We selected five questions related to safety, covering minimal requirements for personal protective equipment (PPE), recommendations for extended use and reuse of PPE, restriction on the number of times healthcare workers enter patients' rooms, hand hygiene, and environmental ventilation. We formulated 21 recommendations that are feasible and affordable in LMICs.

Pain During COVID-19: A Comprehensive Review and Guide for the Interventionalist

BACKGROUND

Chronic pain, the leading cause of disability in the world, imposes limitations on activities of daily living and diminishes quality of life leading to unnecessary patient suffering. The personal and socioeconomic costs of chronic pain cannot be overstated. Physicians are at the crux of the pandemic and must attempt to limit the spread of the virus while maintaining their professional responsibility to their patients and staff members.

OBJECTIVE

The aim of this review is to analyze the existing literature to develop consensus recommendations for treating pain during the current COVID-19 pandemic.

METHODS

Relevant literature was located via computer-generated citations between the months of March and May of 2020. Online computer searches of multiple databases including Google Scholar, CINAHL, PubMed, and Cochrane Review were conducted in conjunction with a thorough review of local, state, national, and international governmental and organizational websites to locate research on the area of interest.

RESULTS

The guidelines in this review are meant to offer a framework to pain practitioners and organizations for providing highly effective, ethical, and safe care to patients while maintaining their commitment to mitigating the spread of the COVID-19 pandemic. Specific areas addressed include general and interventional-specific treatment and mitigation recommendations.

CONCLUSIONS

We believe that the recommendations in this review, if used in conjunction with evolving recommendations of Centers for Disease Control and Prevention (CDC), World Health Organization (WHO), and federal, state, and local governing bodies, provides a path to not only mitigate the spread of the pandemic but also limit the adverse impact of pain and suffering in chronic pain patients.

Efficacy and safety of decontamination for N95 respirator reuse: a systematic literature search and narrative synthesis

PURPOSE

Under times of supply chain stress, the availability of some medical equipment and supplies may become limited. The current pandemic involving severe acute respiratory syndrome coronavirus 2 has highlighted limitations to the ordinary provision of personal protective equipment (PPE). For perioperative healthcare workers, N95 masks provide a stark example of PPE in short supply necessitating the creation of scientifically valid protocols for their decontamination and reuse.

METHODS

We performed a systematic literature search of MEDLINE, Embase, Cochrane CENTRAL databases, and ClinicalTrials.gov to identify peer-reviewed articles related to N95 mask decontamination and subsequent testing for the integrity of mask filtration and facial seal. To expand this search, we additionally surveyed the official statements from key health agencies, organizations, and societies for relevant citations.

RESULTS

Our initial database search resulted in five articles that met inclusion criteria, with 26 articles added from the expanded search. Our search did not reveal any relevant randomized clinical trials or cohort studies. We found that moist mask heating (65-80°C at 50-85% relative humidity for 20-30 min) and vaporous hydrogen peroxide treatment were supported by the literature to provide consistent viral decontamination without compromising mask seal and filtration efficiency. Other investigated decontamination methods lacked comprehensive scientific evidence for all three of these key criteria.

CONCLUSIONS

N95 mask reprocessing using either moist heat or vaporous hydrogen peroxide is recommended to ensure healthcare worker safety.

Decontamination and Reuse of N95 Masks: A Narrative Review

BACKGROUND

The COVID-19 pandemic has presented an unprecedented strain on healthcare supplies. Currently there is a global shortage of personal protective equipment (PPE), especially N95 masks. In order to safeguard healthcare personnel in this critical time and to mitigate shortages of N95 respirators, reuse of N95 respirators has to be considered.

METHODS

Using PubMed and Science Direct, a literature search was conducted to find and synthesize relevant literature on decontamination of N95 respirators for their subsequent reuse. Peer-reviewed publications related to methods of decontamination from January 2007 to April 2020 in the English language are included in this narrative review. Bibliographies of articles for relevant literature were also scrutinized. Findings. A total of 19 studies are included in this narrative review. The appraised methods include ultraviolet germicidal irradiation (UVGI), moist heat incubation (MHI), ethylene oxide (EtO), hydrogen peroxide vapor (HPV), microwave steam bags (MSB), microwave-generated steam (MGS), dry microwave oven irradiation, hydrogen peroxide gas plasma (HPGP), dry heat, liquid hydrogen peroxide, and bleach and alcohol.

CONCLUSION

In light of the COVID-19 pandemic, reuse of N95 respirators, although suboptimal, can be considered. Evidence reveals that UVGI, MHI, and HPV are amongst the safest and efficacious methods for decontamination of N95 masks. More research is needed to establish the safety and effectiveness of MGS, MSB, dry heat, EtO, liquid hydrogen peroxide, and HPGP. Alcohol, microwave irradiation, and bleach are not recommended because they damage N95 respirators.

The impact of extreme reuse and extended wear conditions on protection provided by a surgical-style N95 filtering facepiece respirator

Most respirators employed in health care settings, and often in first responder and industrial settings, are intended for single-use: the user dons the respirator, performs a work activity, and then doffs and discards the respirator. However, in the current COVID-19 pandemic, in the presence of persistent shortages of personal protective equipment, extended use and reuse of filtering facepiece respirators are routinely contemplated by many health care organizations. Further, there is considerable current effort to understand the effect of sterilization on the possibility of reuse, and some investigations of performance have been conducted. While the ability of such a respirator to continue to provide effective protection after repeated sanitization cycles is a critical component of implementing its reuse, of equal importance is an understanding of the impact that reusing the respirator multiple times in a day while performing work tasks, and even extending its wear over multiple days, has on the workplace protective performance. In this study, we subjected a stockpiled quantitatively fitted surgical style N95 filtering facepiece respirator device to extreme reuse and extended wear conditions (up to 19 uses over a duration of 5 days) and measured its protective performance at regular intervals, including simulated workplace protection factor measurements using total inward leakage. With this respirator, it was shown to be possible to maintain protection corresponding to an assigned protection factor greater than 10 under extreme usage conditions provided an individual is properly trained in the use of, and expertly fitted in, the respirator. Other factors such as hygiene and strap breakage are likely to place limits on reuse.

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.

3D-printed snorkel mask adapter for failed N95 fit tests and personal protective equipment shortages

Personal protective equipment (PPE) shortages persist amidst increasing COVID-19 caseloads. These shortages encouraged some to pursue 3D printing to produce stopgap N95 alternatives. The design presented is an adapter for a commercially available snorkel mask to serve as a full-face respirator, used in dire PPE shortages or in individuals who failed fit testing. Masks were fit tested at The University of Kansas Health System in Kansas City, KS. The mask was fit tested on 22 individuals who previously failed fit testing, and all passed qualitative fit testing with the snorkel mask, adapter and viral filter apparatus. The authors endorse this design as a stopgap measure, proven to be effective in situations of dire PPE shortage or for individuals who have failed fit testing with conventional PPE.

A scoping review of surgical masks and N95 filtering facepiece respirators: Learning from the past to guide the future of dentistry

With the 2019 emergence of coronavirus disease 19 (colloquially called COVID-19) came renewed public concern about airborne and aerosolized virus transmission. Accompanying this concern were many conflicting dialogues about which forms of personal protective equipment best protect dental health care practitioners and their patients from viral exposure. In this comprehensive review we provide a thorough and critical assessment of face masks and face shields, some of the most frequently recommended personal safeguards against viral infection. We begin by describing the function and practicality of the most common mask types used in dentistry: procedural masks, surgical masks, and filtering respirator facemasks (also called N95s). This is followed by a critical assessment of mask use based on a review of published evidence in three key domains: the degree to which each mask type is shown to protect against airborne and aerosolized disease, the reported likelihood for non-compliance among mask users, and risk factors associated with both proper and improper mask use. We use this information to conclude our review with several practical, evidence-based recommendations for mask use in dental and dental educational clinics.

Polylactic acid as a suitable material for 3D printing of protective masks in times of COVID-19 pandemic

A critical lack of personal protective equipment has occurred during the COVID-19 pandemic. Polylactic acid (PLA), a polyester made from renewable natural resources, can be exploited for 3D printing of protective face masks using the Fused Deposition Modelling technique. Since the possible high porosity of this material raised questions regarding its suitability for protection against viruses, we have investigated its microstructure using scanning electron microscopy and aerosol generator and photometer certified as the test system according to the standards EN 143 and EN 149. Moreover, the efficiency of decontaminating PLA surfaces by conventional chemical disinfectants including 96% ethanol, 70% isopropanol, and a commercial disinfectant containing 0.85% sodium hypochlorite has been determined. We confirmed that the structure of PLA protective masks is compact and can be considered a sufficient barrier protection against particles of a size corresponding to microorganisms including viruses. Complete decontamination of PLA surfaces from externally applied Staphylococcus epidermidis, Escherichia coli, Candida albicans and SARS-CoV-2 was achieved using all disinfectants tested, and human adenovirus was completely inactivated by sodium hypochlorite-containing disinfectant. Natural contamination of PLA masks worn by test persons was decontaminated easily and efficiently by ethanol. No disinfectant caused major changes to the PLA surface properties, and the pore size did not change despite severe mechanical damage of the surface. Therefore, PLA may be regarded as a suitable material for 3D printing of protective masks during the current or future pandemic crises.

Evaluation of Regeneration Processes for Filtering Facepiece Respirators in Terms of the Bacteria Inactivation Efficiency and Influences on Filtration Performance

The regeneration of filtering facepiece respirators (FFRs) is of critical importance because of the severe shortage of FFRs during large-scale outbreaks of respiratory epidemics, such as COVID-19. Comprehensive experiments regarding FFR regeneration were performed in this study with model bacteria to illustrate the decontamination performance of the regeneration processes. The results showed that it is dangerous to use a contaminated FFR without any microbe inactivation treatment because the bacteria can live for more than 8 h. The filtration efficiency and surface electrostatic potential of 75% ethanol-treated FFRs were significantly reduced, and a most penetrating particle size of 200 nm was observed. Steam and microwave irradiation (MWI) showed promising decontamination performances, achieving 100% inactivation in 90 and 30 min, respectively. The filtration efficiencies of steam-treated FFRs for 50 and 100 nm particles decreased from 98.86% and 99.51% to 97.58% and 98.79%, respectively. Ultraviolet irradiation (UVI) effectively inactivated the surface bacteria with a short treatment of 5 min and did not affect the filtration performance. However, the UV dose reaching different layers of the FFP2 mask sample gradually decreased from the outermost layer to the innermost layer, while the model bacteria on the second and third layers could not be killed completely. UVI+MWI and steam were recommended to effectively decontaminate the used respirators and still maintain the respirators' filtration efficiency. The present work provides a comprehensive evaluation for FFR regeneration in terms of the filtration efficiencies for 50-500 nm particles, the electrostatic properties, mechanical properties, and decontamination effects.

Selection of homemade mask materials for preventing transmission of COVID-19: A laboratory study

The Coronavirus Disease 2019 (COVID-19) has swept the whole world with high mortality. Since droplet transmission is the main route of transmission, wearing a mask serves as a crucial preventive measure. However, the virus has spread quite quickly, causing severe mask shortage. Finding alternative materials for homemade masks while ensuring the significant performance indicators will help alleviate the shortage of masks. Referring to the national standard for the "Surgical Mask" of China, 17 materials to be selected for homemade masks were tested in four key indicators: pressure difference, particle filtration efficiency, bacterial filtration efficiency and resistance to surface wetting. Eleven single-layer materials met the standard of pressure difference (≤49 Pa), of which 3 met the standard of resistance to surface wetting (≥3), 1 met the standard of particle filtration efficiency (≥30%), but none met the standard of bacterial filtration efficiency (≥95%). Based on the testing results of single-layer materials, fifteen combinations of paired materials were tested. The results showed that three double-layer materials including double-layer medical non-woven fabric, medical non-woven fabric plus non-woven shopping bag, and medical non-woven fabric plus granular tea towel could meet all the standards of pressure difference, particle filtration efficiency, and resistance to surface wetting, and were close to the standard of the bacterial filtration efficiency. In conclusion, if resources are severely lacking and medical masks cannot be obtained, homemade masks using available materials, based on the results of this study, can minimize the chance of infection to the maximum extent.

A Review of Decontamination Methods for Filtering Facepiece Respirators

During the current COVID-19 infectious disease pandemic, the demand for NIOSH-approved filtering facepiece respirators (FFR) has exceeded supplies and decontamination and reuse of FFRs has been implemented by various user groups. FFR decontamination and reuse is only intended to be implemented as a crisis capacity strategy. This paper provides a review of decontamination procedures in the published literature and calls attention to their benefits and limitations. In most cases, the data are limited to a few FFR models and a limited number of decontamination cycles. Institutions planning to implement a decontamination method must understand its limitations in terms of the degree of inactivation of the intended microorganisms and the treatment's effects on the fit and filtration of the device.

COVID-19 and paediatric dentistry- traversing the challenges. A narrative review

The coronavirus disease (COVID-19) pandemic has become a major global public health emergency with a focus on preventing the spread of this virus for controlling this crisis. A dental setting is at a high risk of cross infection amid patients and dental practitioner's owing to the spread of infection via droplets suspended in the air by infected symptomatic or asymptomatic subjects. This review article informs about measures which reduce facility risk, manage symptomatic patients and protect personal health care and management with reference to paediatric dentistry.

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.

The COVID-19 pandemic, personal protective equipment and respirator: A narrative review

INTRODUCTION

The coronavirus disease 2019 pandemic has touched almost every continent. Personal protective equipment (PPE) is the final line of protection of healthcare workers (HCW). There is variation as well as controversy of infection control recommendation with regards to the use of PPE for HCW between institutions. The aim of this narrative review is to of examine and summarise the available evidence to guide recommendation for the safety of HCW.

METHOD

A literature search was conducted on the PubMed, MedLine and Embase databases with the keywords "personal protective equipment," "COVID 19," "n95," "health care worker" and "mortality."

RESULTS

SARS-nCoV-2 is highly contagious. About 3.5%-20% of HCW has been reported to be infected. The mortality ranges from 0.53% to 1.94%. PPE is part of the measure within a package of prevention and control of pandemic, rather than a replacement of. Respirators are more effective than masks in preventing aerosol transmission to HCWs. Extended use may be considered if guidelines are adhered. Powered air-purifying respirators if available should be used in high-risk procedures.

CONCLUSION

Transmission of viruses is multimodal and in the setting of a novel pathogen with high case fatality with no proven effective interventions, PPE that affords the best protection should be available to HCWs.