Bioinspired Structures Made of Silicone Nanofilaments for Upcycling Waste Masks to Reusable N95 Respirators.

The increasing demand for personal protective equipment such as single-use masks has led to large amounts of nondegradable plastic waste, aggravating economic and environmental burdens. This study reports a simple and scalable approach for upcycling waste masks via a chemical vapor deposition technique, realizing a trichome-like biomimetic (TLB) N95 respirator with superhydrophobicity (water contact angle ≥150°), N95-level protection, and reusability. The TLB N95 respirator comprising templated silicone nanofilaments with an average diameter of ∼150 nm offers N95-level protection and breathability comparable to those of commercial N95 respirators. The TLB N95 respirator can still maintain its N95-level protection against particulate matter and viruses after 10 disinfection treatment cycles (i.e., ultraviolet irradiation, microwave irradiation, dry heating, and autoclaving), demonstrating durable reusability. The proposed strategy provides new insight into upcycle waste masks, breaking the existing design and preparation concept of reusable masks.

Development of a rapid, multi-organisational, multi-modal assessment of a newly available disposable respirator.

BACKGROUND: A rapid large-scale evaluation of a newly available duckbill style P2/N95 respirator, the Care Essentials (CE) MSK-003, was required to determine its suitability for deployment into the Victorian healthcare service. The aims of this study were to assess the feasibility of establishing a rapid, multi-organisational and multi-modal evaluation of the respirator, and to investigate whether this respirator would meet the needs of healthcare workers. METHODS: The evaluation was a collaboration among three healthcare organisations - two tertiary hospitals in metropolitan Melbourne and a rural-based hospital. Participants were healthcare workers undertaking their routine fit tests. They were required to complete quantitative fit testing and a usability assessment survey on the CE MSK-003 respirator. The a priori performance criteria were set as fit test pass rate of >70%, plus satisfactory subjective overall comfort and performance assessments, defined as a rating of adequate, good, or very good in >90% of the cohort. RESULTS: A total of 1070 participants completed the multi-modal assessment within a month. Seventy-eight percent of participants passed their quantitative fit test. Over 90% of survey respondents reported that the CE MSK-003 was adequate, good or very good in terms of its overall comfort and performance assessments. CONCLUSION: We demonstrated that a multi-modal evaluation of a new respirator can be rapidly conducted with a high level of participation in a controlled, consistent manner across multiple organisations. The evaluation results of the CE MSK-003 respirator exceeded our predetermined (a priori) minimal criteria, making it suitable for broad distribution to healthcare organisations.

Use of Hydrogen Peroxide Vapour for Microbiological Disinfection in Hospital Environments: A Review.

Disinfection of nosocomial pathogens in hospitals is crucial to combat healthcare-acquired infections, which can be acquired by patients, visitors and healthcare workers. However, the presence of a wide range of pathogens and biofilms, combined with the indiscriminate use of antibiotics, presents infection control teams in healthcare facilities with ongoing challenges in the selection of biocides and application methods. This necessitates the development of biocides and innovative disinfection methods that overcome the shortcomings of conventional methods. This comprehensive review finds the use of hydrogen peroxide vapour to be a superior alternative to conventional methods. Motivated by observations in previous studies, herein, we provide a comprehensive overview on the utilisation of hydrogen peroxide vapour as a superior high-level disinfection alternative in hospital settings. This review finds hydrogen peroxide vapour to be very close to an ideal disinfectant due to its proven efficacy against a wide range of microorganisms, safety to use, lack of toxicity concerns and good material compatibility. The superiority of hydrogen peroxide vapour was recently demonstrated in the case of decontamination of N95/FFP2 masks for reuse to address the critical shortage caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during the COVID-19 pandemic. Despite the significant number of studies demonstrating antimicrobial activity, there remains a need to critically understand the mechanism of action by performing studies that simultaneously measure damage to all bacterial cell components and assess the correlation of this damage with a reduction in viable cell count. This can lead to improvement in antimicrobial efficacy and foster the development of superior approaches.

Corrigendum: Evaluation of N95 respirators on fit rate, real-time leakage, and usability among Chinese healthcare workers: study protocol of a randomized crossover trial.

[This corrects the article DOI: 10.3389/fpubh.2023.1266607.].

Integrity and filtration efficiency of decontaminated N95/PFF2 masks to protect health care professionals against COVID-19: A systematic literature review and meta-analysis.

BACKGROUND: To evaluate the evidence related to maintaining the integrity and filtration efficiency of N95 and/or PFF2 respirators after decontamination in health care professionals' protection against COVID-19. METHODS: Systematic review, developed based on the guidelines from Joanna Briggs Institute for syntheses focusing on effectiveness evidence. The protocol was registered on the International Prospective Register of Ongoing Systematic Reviews platform, under the number CRD42022354256. This study report was developed in accordance with the guidelines recommended by the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Publications between January 2020 and August 2022 were selected of Embase, Medline, CINAHL, Web of Science, Cochrane, SciELO and Virtual Health Library databases. Joanna Briggs critical appraisal tool for nonrandomized experimental tests was used to evaluate the evidence quality. RESULTS: Seven articles were included in the data extraction and critical evaluation, and 3 in the meta-analysis. Four studies evaluated the integrity by visual inspection and 2 by electron microscopy. There was no association between the number of cycles increase and the reduction in filtration in up to 10 cycles. None study was considered of high methodological quality. CONCLUSIONS: There is some evidence that integrity and filtration capacity were maintained after decontamination of N95/PFF2 respirators to prevent COVID-19.

Eustachian tube dysfunction after using different types of masks during the coronavirus disease 2019 pandemic.

OBJECTIVE: This study aimed to investigate the relationship between the use of different types of masks (N95/filtering facepiece type 2, surgical) and Eustachian tube dysfunction in healthcare workers. METHODS: The study included 37 healthcare workers using N95/filtering facepiece type 2 masks and 35 using surgical masks for at least 6 hours per day, and 42 volunteers who are not healthcare workers using surgical masks for less than 6 hours per day. Participants' demographic features, clinical data and Eustachian Tube Dysfunction Questionnaire scores were compared. RESULTS: The frequencies of autophony and aural fullness were significantly higher in the healthcare workers using N95/filtering facepiece type 2 masks. Autophony and aural fullness were significantly greater in the post-mask period than the pre-mask period. Middle-ear peak pressures and Eustachian Tube Dysfunction Questionnaire scores were higher in healthcare workers who used N95/filtering facepiece type 2 masks. CONCLUSION: Healthcare workers who used N95/filtering facepiece type 2 masks had worsened middle-ear pressures and Eustachian Tube Dysfunction Questionnaire scores. Use of N95/filtering facepiece type 2 masks was associated with higher rates of autophony, aural fullness and higher Eustachian Tube Dysfunction Questionnaire scores in the post-mask period.

Evaluation of N95 respirators on fit rate, real-time leakage, and usability among Chinese healthcare workers: study protocol of a randomized crossover trial.

Background: N95 respirators are used to limit the transmission of respiratory viruses in clinical settings. There are two to three major types of N95 available for all healthcare workers in Hong Kong. However, after the coronavirus outbreak and the consequent shortage of many commonly used respirators, several new N95 respirators were adopted temporarily in clinical settings without evaluation. Prior literature indicates that traditional N95 respirators used in hospitals in Hong Kong are not fit for Chinese people and have fit rates ranging from 50 to 60%. This study aims to investigate and compare the fit rate, real-time leakage, and mask usability of traditional and new N95 respirators among Chinese healthcare workers. Methods: This study will employ two sequential phases. Phase 1 has a cross-sectional exploratory design used to investigate the fit rate and mask usability of three types of respirators. Phase 2 will examine the effectiveness of respiratory protection by comparing traditional and new N95 respirators by a randomized crossover trial. Eligible participants will be randomly allocated through a controlled crossover experiment to either a traditional or new respirator group (n = 100 in each arm) for performing standard clinical procedures. The primary outcome (real-time leakage) will be recorded at 30 s intervals during nasopharyngeal suctioning and cardiopulmonary resuscitation. The secondary outcomes are the fit rate and mask usability. After a 2 min suctioning (15 s twice) and 4 min one-person CPR, the fit rate (assessed by standard N95 fit testing) and mask usability (measured by self-reported mask usability scale) will be recorded as data of post-procedure. After 10 min rest, measurement of real-time leakage (i.e., crossover), fit test, and usability will be repeated. Discussion: The result of real-time leakage will be a vital indicator of the respiratory protection of Chinese healthcare workers while performing prevalent clinical procedures, such as resuscitation. The fit rate and usability result will serve as an essential reference for consumable purchase policy in clinical settings.Trial registration: ISRCTN registry: ISRCTN40115047. Retrospectively registered on May 9, 2023. https://www.isrctn.com/ISRCTN40115047.

Lesiones cutáneas asociadas con el uso de respiradores N95 en profesionales de la salud de Brasil durante 2020 / Skin lesions associated with the use of N95 respirators among health professionals in Brazil in 2020 / Lesões de pele associadas ao uso de respiradores N95 entre profissionais de saúde no Brasil em 2020

Objetivo: investigar la prevalencia de lesiones cutáneas y factores asociados con el uso de respiradores N95 en profesionales de la salud de Brasil. Método: estudio transversal realizado con 11.368 profesionales de la salud en el que se empleó un método de muestreo dirigido por encuestados adaptado para entornos en línea. Se ejecutaron análisis univariados y multivariados para investigar la asociación entre la variable "lesiones cutáneas por utilizar respiradores N95" y sexo, categoría profesional, lugar de trabajo, capacitación, diagnóstico de COVID-19 y disponibilidad de suficiente provisión de Equipo de Protección Personal de buena calidad. Resultados: la prevalencia de lesiones cutáneas fue del 61,8%. Las mujeres fueron 1,203 veces (IC 95%: 1,154-1,255) más propensas a desarrollar lesiones que los hombres. La probabilidad de lesiones cutáneas en psicólogos (RP=0,805; IC 95%: 0,678-0,956) y dentistas (RP=0,884; IC 95%: 0,788-0,992) fue menor en comparación con la encontrada en los profesionales de Enfermería. Los profesionales con diagnóstico positivo de COVID-19 y que trabajan en la Unidad de Cuidados Intensivos son más propensos a sufrir lesiones cutáneas (RP=1,074; IC 95%: 1,042-1,107); (RP=1,203; IC 95%: 1,168-1,241), respectivamente, Conclusión: la prevalencia de lesiones cutáneas causadas por utilizar respiradores N95 fue del 61,8% y estuvo asociada al sexo femenino, a la categoría profesional, al lugar de trabajo, a la capacitación, a diagnóstico de COVID-19 y a la disponibilidad de suficiente provisión de Equipo de Protección Personal de buena calidad.

Objective: to investigate the prevalence of skin lesions and factors associated with the use of N95 respirators among health professionals in Brazil. Method: cross-sectional study conducted with 11,368 health professionals using a respondent-driven sampling method adapted for online environments. Univariate and multivariate analyses were performed to investigate the association between the "skin lesions with the use of N95 respirators" variable and gender, professional category, workplace, training, COVID-19 diagnosis, and availability of sufficient and high-quality Personal Protective Equipment. Results: the prevalence of skin lesions was 61.8%. Women were 1.203 times (95% CI: 1.154-1.255) more likely to develop a lesion than men. The chances of skin lesions in psychologists (PR=0.805; 95% CI: 0.678-0.956) and dentists (PR=0.884; 95% CI: 0.788-0.992), were lower when compared to Nursing professionals. Professionals with a positive COVID-19 diagnosis and working in the Intensive Care Unit have an increased chance of presenting skin lesions (PR=1.074; 95% CI: 1.042-1.107); (PR=1.203; 95% CI: 1.168-1.241), respectively. Conclusion: the prevalence of skin lesions caused by the use of N95 respirators was 61.8% and was associated with female gender, professional category, workplace, training, COVID-19 diagnosis, and availability of sufficient and highquality Personal Protective Equipment.

Objetivo: investigar a prevalência de lesões de pele e fatores associados ao uso de respiradores N95 entre profissionais de saúde no Brasil. Método: estudo transversal realizado com 11.368 profissionais de saúde por meio de um método de amostragem dirigido por respondentes adaptado para ambientes online. Análises univariadas e multivariadas foram realizadas para investigar a associação entre a variável "lesão de pele com uso de respirador N95" e sexo, categoria profissional, local de trabalho, treinamento, diagnóstico de COVID-19 e disponibilidade suficiente de equipamentos de proteção individual de qualidade. Resultados: a prevalência de lesões cutâneas foi de 61,8%. As mulheres foram 1,203 vezes (IC 95%: 1.154-1.255) mais propensas a desenvolver uma lesão do que os homens. As chances de lesão de pele em psicólogos (RP=0,805; IC 95%: 0,678-0,956) e dentistas (RP=0,884; IC 95%: 0,788-0,992) foram menores quando comparados aos profissionais de Enfermagem. Profissionais com diagnóstico positivo para COVID-19 e que trabalham em Unidade de Cuidados Intensivos têm maior chance de apresentar lesões de pele (RP=1,074; IC 95%: 1,042-1,107); (RP=1,203; IC 95%: 1,168- 1,241), respectivamente. Conclusão: a prevalência de lesões de pele causadas pelo uso do respirador N95 foi de 61,8% e esteve associada ao sexo feminino, categoria profissional, local de trabalho, treinamento, diagnóstico de COVID-19 e disponibilidade suficiente de equipamentos de proteção individual de qualidade.

A systematic review and meta-analysis of the efficacy of N95 respirators and surgical masks for protection against COVID-19.

Former meta-analyses concluded that there was not sufficient evidence to determine the effect of surgical masks and N95 respirators. We collected randomized controlled trials (RCTs) and conducted a systematic review and meta-analysis to evaluate the efficacy of N95 respirators and surgical masks for protection against COVID-19. We retrieved relevant RCTs published between January 2019 and January 2023 by searching the PubMed, EMBASE, and Cochrane CENTRAL. Study quality was evaluated using the Cochrane Risk of Bias tool with the RevMan 5.4 software. Meta-analyses were conducted to calculate pooled estimates using the RevMan 5.4 software. A total of six RCTs were finally included. The findings revealed that wearing a mark made little difference in preventing COVID-19 [odds ratio (OR) = 0.10; 95% confidence interval (CI): 0.01-0.93; P = 0.04]. Subgroup analysis showed that the heterogeneity of data was I2 = 64% (OR = 0.32; 95% CI: 0.06-1.77; P = 0.19) for surgical mask use and I2 = 0% (OR = 0.03; 95 %CI: 0.01-0.15; P < 0.01) for N95 respirator use. The heterogeneity of data for medical staff was I2 = 0% (OR = 0.03; 95 %CI: 0.01-0.12; P < 0.01). Meta-analysis indicated a protective effect of N95 respirators against COVID-19, particularly for medical staff. The use of surgical masks is not associated with a lower risk of COVID-19. However, the subgroup using N95 respirators, particularly medical staff, showed a significant protective. These findings suggest that N95 respirators should be reserved for high-risk medical staff in the absence of sufficient resources during an epidemic. But the number of included studies was small, more studies in future analyses is required to reduce the risk of distribution bias.

Physiological effects of N95 respirators on rescuers during cardiopulmonary resuscitation.

Objectives: There is a lack of evidence in the medical literature reporting the physiological stress imposed by the wearing of N95 respirators during cardiopulmonary resuscitation (CPR) in healthcare providers. The aim of this study is to monitor the changes in hemodynamics and blood gas profiles in rescuers during the performance of CPR while wearing N95 respirators. Methods: Thirty-two healthy healthcare workers performed standard CPR on manikins, each participant conducted 2 min of chest compression followed by 2 min of rest for 3 cycles. A non-invasive blood gas measuring device via a fingertip detector was used to collect arterial blood gas and hemodynamic data. Student t-test was used for comparison of various physiologic parameters before and after each session of chest compression. Results: There were no significant differences in arterial blood gas profiles including partial pressure of arterial carbon dioxide and partial pressure of arterial oxygen before and after each session of chest compression (p > 0.05 for all). Heart rate and cardiac output were significantly higher after CPR (p < 0.05 for all), but no significant changes were found on blood pressure. Conclusions: Our data suggest that healthcare providers wearing N95 respirators during provision of CPR in a short period of time does not cause any significant abnormalities in blood gas profiles and blood pressure. This may provide evidence to reassure the safe use of N95 respirator during performance of CPR.

Aerosol protection using modified N95 respirator during upper gastrointestinal endoscopy: a randomized controlled trial.

Background/Aims: The coronavirus disease 2019 pandemic has affected the worldwide practice of upper gastrointestinal endoscopy. Here we designed a modified N95 respirator with a channel for endoscope insertion and evaluated its efficacy in upper gastrointestinal endoscopy. Methods: Thirty patients scheduled for upper gastrointestinal endoscopy were randomized into the modified N95 (n=15) or control (n=15) group. The mask was placed on the patient after anesthesia administration and particles were counted every minute before (baseline) and during the procedure by a TSI AeroTrak particle counter (9306-04; TSI Inc.) and categorized by size (0.3, 0.5, 1, 3, 5, and 10 µm). Differences in particle counts between time points were recorded. Results: During the procedure, the modified N95 group displayed significantly smaller overall particle sizes than the control group (median [interquartile range], 231 [54-385] vs. 579 [213-1,379]×103/m3; p=0.056). However, the intervention group had a significant decrease in 0.3-µm particles (68 [-25-185] vs. 242 [72-588]×103/m3; p=0.045). No adverse events occurred in either group. The device did not cause any inconvenience to the endoscopists or patients. Conclusions: This modified N95 respirator reduced the number of particles, especially 0.3-µm particles, generated during upper gastrointestinal endoscopy.

Innovations with Validation: An Ingenious Way Forward?

How to cite this article: Ajith Kumar AK, Nikhil N. Innovations with Validation: An Ingenious Way Forward? Indian J Crit Care Med 2023;27(6):377-378.

Safety Goggles with Elastic Headband to Improve N95 Fit Following Failed Quantitative Fit Test.

Introduction: N95 respirators, together with eye protection, form vital elements of personal protective equipment (PPE) for healthcare workers (HCW) caring for patients with respiratory infections, such as COVID-19. Duckbill N95 respirators are widely used but have a high failure rate when Fit Tested. The commonest site for inward leaks is the region between the nose and maxilla. Safety goggles with an elastic headband may press the upper rim of the respirator against the face, thereby reducing inward leaks. We hypothesized that the use of safety goggles with an elastic headband will improve the overall fit-factor of a duckbill N95 respirator and increase the proportion of users who pass a quantitative Fit Test. Methods: About 60 volunteer HCWs, who had previously failed quantitative Fit Testing with a duckbill N95 respirator, participated in this before-and-after intervention study. A PortaCount® 8048 was used for quantitative Fit Testing. The test was first performed with a duckbill N95 respirator only. It was then repeated after participants donned a pair of safety goggles (3M Fahrenheit, ID 70071531621). Results: Before the intervention, i.e., with the respirator only, 8 (13.3%) participants passed their Fit Test. This increased to 49 (81.7%) after the application of safety goggles (OR 42, 95% CI 7.14-1697.9, p < 0.0001). The adjusted mean overall fit factor, using Tobit regression analysis, increased from 40.3 to 193.0 (t = 12.32, p < 0.001). Conclusion: The use of safety goggles with an elastic headband significantly increases the proportion of users who pass a quantitative Fit Test and improves the fit-factor of a duckbill N95 respirator. How to cite this article: Kamal M, Bhatti M, Stewart WC, Johns M, Collins D, Shehabi Y, et al. Safety Goggles with Elastic Headband to Improve N95 Fit Following Failed Quantitative Fit Test. Indian J Crit Care Med 2023;27(6):386-391.

A framework for comparing N95 and elastomeric facepiece respirators on cost and function for healthcare use during a pandemic- A literature review.

SARS-CoV-2 has posed implications for personal protective equipment supply. In this literature review we examine if elastomeric facepiece respirators (EFRs) are effective substitutes for N95 respirators through comparing their functionality and cost. We reviewed 30 articles which researched the advantages and disadvantages of each respirator. We compiled the reported results and found, among other things, that users favour N95 respirators for comfort but prefer EFRs for protection. EFRs are more cost effective when N95s are used as designed (single use) but mixed strategies minimize costs when N95s are reused (as practiced during shortages). Future research is needed on multicriteria analyses and to incorporate SARS-CoV-2 specific data to support future pandemic planning.

Comparison of mild physiological effects of surgical masks and N95 respirators over 60 min at rest.

Dead-space-associated rebreathing of expired air and heat trapping with use of surgical masks and N95 respirators may underlie anecdotal reports of adverse symptoms associated with medical face barriers. Limited data exist directly comparing the physiological effects of masks and respirators at rest. We assessed the short-term physiological effects of both barrier types over 60 min at rest, including face microclimate temperature, end-tidal gases, and venous blood acid-base variables. We recruited 34 participants into two trials: surgical masks (n = 17) and N95 respirators (n = 17). In a seated position, participants underwent a 10-min baseline without a barrier and then wore a standardized surgical mask or dome-shaped N95 respirator for 60 min, followed by a 10-min washout. We instrumented healthy human participants with a peripheral pulse oximeter ([Formula: see text]) and a nasal cannula connected to a dual gas analyzer for measurement of the pressure of end-tidal [Formula: see text] and [Formula: see text], with an associated temperature probe for face microclimate temperature. Venous (v) blood samples were obtained at baseline and following 60-min mask/respirator wearing to assess [Formula: see text], [HCO3-]v and pHv. Compared with baseline during/following 60 min, temperature, [Formula: see text], [Formula: see text], and [HCO3-]v were mildly but significantly higher, and [Formula: see text] and [Formula: see text] were significantly lower, but [Formula: see text] was unaffected. The magnitude of effects was similar between barrier types. Temperature and [Formula: see text] returned to baseline levels within 1-2 min following removal of the barrier. These mild physiological effects may underlie reports of qualitative symptoms while wearing masks or respirators. However, the magnitudes were mild, not physiologically relevant and reversed immediately with the removal of the barrier.NEW & NOTEWORTHY Anecdotal reports suggest mild physiological effects of wearing surgical masks and/or N95 respirators, including heat trapping and rebreathing of expired air. There are limited data directly comparing the physiological effects of wearing medical barriers at rest. We found that the time course and magnitude of changes to face microclimate temperature, end-tidal gases, and venous blood gases and acid-base variables were mild in magnitude, not physiologically relevant, equivalent between barrier types, and immediately reversible on removal.

Physio-metabolic and clinical consequences of wearing face masks-Systematic review with meta-analysis and comprehensive evaluation.

Background: As face masks became mandatory in most countries during the COVID-19 pandemic, adverse effects require substantiated investigation. Methods: A systematic review of 2,168 studies on adverse medical mask effects yielded 54 publications for synthesis and 37 studies for meta-analysis (on n = 8,641, m = 2,482, f = 6,159, age = 34.8 ± 12.5). The median trial duration was only 18 min (IQR = 50) for our comprehensive evaluation of mask induced physio-metabolic and clinical outcomes. Results: We found significant effects in both medical surgical and N95 masks, with a greater impact of the second. These effects included decreased SpO2 (overall Standard Mean Difference, SMD = -0.24, 95% CI = -0.38 to -0.11, p < 0.001) and minute ventilation (SMD = -0.72, 95% CI = -0.99 to -0.46, p < 0.001), simultaneous increased in blood-CO2 (SMD = +0.64, 95% CI = 0.31-0.96, p < 0.001), heart rate (N95: SMD = +0.22, 95% CI = 0.03-0.41, p = 0.02), systolic blood pressure (surgical: SMD = +0.21, 95% CI = 0.03-0.39, p = 0.02), skin temperature (overall SMD = +0.80 95% CI = 0.23-1.38, p = 0.006) and humidity (SMD +2.24, 95% CI = 1.32-3.17, p < 0.001). Effects on exertion (overall SMD = +0.9, surgical = +0.63, N95 = +1.19), discomfort (SMD = +1.16), dyspnoea (SMD = +1.46), heat (SMD = +0.70), and humidity (SMD = +0.9) were significant in n = 373 with a robust relationship to mask wearing (p < 0.006 to p < 0.001). Pooled symptom prevalence (n = 8,128) was significant for: headache (62%, p < 0.001), acne (38%, p < 0.001), skin irritation (36%, p < 0.001), dyspnoea (33%, p < 0.001), heat (26%, p < 0.001), itching (26%, p < 0.001), voice disorder (23%, p < 0.03), and dizziness (5%, p = 0.01). Discussion: Masks interfered with O2-uptake and CO2-release and compromised respiratory compensation. Though evaluated wearing durations are shorter than daily/prolonged use, outcomes independently validate mask-induced exhaustion-syndrome (MIES) and down-stream physio-metabolic disfunctions. MIES can have long-term clinical consequences, especially for vulnerable groups. So far, several mask related symptoms may have been misinterpreted as long COVID-19 symptoms. In any case, the possible MIES contrasts with the WHO definition of health. Conclusion: Face mask side-effects must be assessed (risk-benefit) against the available evidence of their effectiveness against viral transmissions. In the absence of strong empirical evidence of effectiveness, mask wearing should not be mandated let alone enforced by law. Systematic review registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021256694, identifier: PROSPERO 2021 CRD42021256694.

Nosocomial SARS-CoV-2 transmission in multi-bedded hospital cubicles over successive pandemic waves: Lower mortality but wider spread with Omicron despite enhanced infection-prevention measures.

BACKGROUND: Increased transmissibility of severe-acute-respiratory-syndrome-coronavirus-2(SARS-CoV-2) variants, such as the Omicron-variant, presents an infection-control challenge. We contrasted nosocomial transmission amongst hospitalized inpatients across successive pandemic waves attributed to the Delta- and Omicron variants, over a 9-month period in which enhanced-infection-prevention-measures were constantly maintained. METHODS: Enhanced-infection-prevention-measures in-place at a large tertiary hospital included universal N95-usage, routine-rostered-testing (RRT) for all inpatient/healthcare-workers (HCWs), rapid-antigen-testing (RAT) for visitors, and outbreak-investigation coupled with enhanced-surveillance (daily-testing) of exposed patients. The study-period lasted from 21st June 2021-21st March 2022. Chi-square test and multivariate-logistic-regression was utilized to identify factors associated with onward transmission and 28d-mortality amongst inpatient cases of hospital-onset COVID-19. RESULTS: During the Delta-wave, hospital-onset cases formed 2.7% (47/1727) of all COVID-19 cases requiring hospitalisation; in contrast, hospital onset-cases formed a greater proportion (17.7%, 265/1483; odds-ratio, OR = 7.78, 95%CI = 5.65-10.70) during the Omicron-wave, despite universal N95-usage and other enhanced infection-prevention measures that remained unchanged. The odds of 28d-mortality were higher during the Delta-wave compared to the Omicron-wave (27.7%, 13/47, vs. 10.6%, 28/265, adjusted-odds-ratio, aOR = 2.78, 95%CI = 1.02-7.69). Onward-transmission occurred in 21.2% (66/312) of hospital-onset cases; being on enhanced-surveillance (daily-testing) was independently associated with lower odds of onward-transmission (aOR = 0.18, 95%CI = 0.09-0.38). Costs amounted to $USD7141 per-hospital-onset COVID-19 case. CONCLUSION: A surge of hospital-onset COVID-19 cases was encountered during the Omicron-wave, despite continuation of enhanced infection-prevention measures; mortality amongst hospital-onset cases was reduced. The Omicron variant poses an infection-control challenge in contrast to Delta; surveillance is important especially in settings where infrastructural limitations make room-sharing unavoidable, despite the high risk of transmission.

Qualitative fit test outcomes for N95 filtering facepiece respirators in health care workers.

BACKGROUND: We analyzed the qualitative fit test results of the filtering facepiece respirators (FFRs) used at our institution to determine their performance and utility. METHODS: We retrospectively analyzed 12,582 qualitative fit testing results for several FFR models among 8,809 health care workers (HCWs). RESULTS: The overall failure rate for HCWs was 15.2%. Nearly one-third (2933/8809, 33.3%) had multiple FFRs fit tested. HCW sex was a statistically significant indicator of fit testing failure (χ2 = 29.9, df = 1, P < .001), with women having a 44% higher likelihood (OR, 1.4; 95% CI: 1.27-1.65) than men. There were statistically significant differences in the failure rate across FFRs (Fig 4, F[5, 12475] = 8.4, P < .001). Fluidshield 46867S had a significantly higher failure rate (49%) than the 3M 1860 (P = .012), 3M 1860S (P < .001), 3M 8210 (P < .001), and Safelife (P < .001) FFRs. CONCLUSIONS: There was a large degree of variation in fit testing results for the FFRs tested. Although we were unable to find an FFR that fit more than 95% of the HCWs successfully, we identified poorly functioning FFRs that can help our institution with decision-making and budgeting for acquisition and stocking appropriate FFRs.

The effect of N95 respirators on vital parameters, PETCO2, among healthcare providers at the pandemic clinics.

BACKGROUND: Wearing face shields and masks, which used to have very limited public use before the COVID-19 outbreak, has been highly recommended by organizations, such as CDC and WHO, during this pandemic period. AIMS: The aim of this prospective study is to scrutinize the dynamic changes in vital parameters, change in end tidal CO2 (PETCO2) levels, the relationship of these changes with taking a break, and the subjective complaints caused by respiratory protection, while healthcare providers are performing their duties with the N95 mask. METHODS: The prospective cohort included 54 healthcare workers (doctors, nurses, paramedics) who worked in the respiratory unit of the emergency department (ED) and performed their duties by wearing valved N95 masks and face shields. The vital parameters and PETCO2 levels were measured at 0-4th-5th and 9th hours of the work-shift. RESULTS: Only the decrease in diastolic BP between 0 and 9 h was statistically significant (p = 0.038). Besides, mean arterial pressure (MAP) values indicated a significant decrease between 0-9 h and 5-9 h (p = 0.024 and p = 0.049, respectively). In terms of the vital parameters of the subjects working with and without breaks, only PETCO2 levels of those working uninterruptedly increased significantly at the 4th hour in comparison to the beginning-of-shift baseline levels (p = 0.003). CONCLUSION: Although the decrease in systolic blood pressure (SBP) and MAP values is assumed to be caused by increased fatigue due to workload and work pace as well as increase in muscle activity, the increase in PETCO2 levels in the ED healthcare staff working with no breaks between 0 and 4 h should be noted in terms of PPE-induced hypoventilation.