A randomised clinical trial to evaluate the safety, fit, comfort of a novel N95 mask in children

Children's experiences of mask-wearing: a systemic review and narrative synthesis

RATIONALE

Masks have been widely used as a preventative tool during the COVID-19 pandemic. However, the use of masks by children has been controversial, with international guidelines recommending a risk-based approach to national policymakers.

AIMS AND OBJECTIVES

We aimed to conduct a systematic review that explores children's experiences of mask-wearing, drawing on an evidence base that describes mask-wearing in different contexts including air pollution, and to prevent the spread of infectious disease.

METHODS

We searched MEDLINE, Embase and PsycINFO in June 2021, with repeat searches in August 2022 and January 2024, for primary research studies exploring children's experiences of masks. Included studies reported on participants between 4 and 14 years (inclusive), with no restrictions on language where an English translation was available. Two reviewers independently screened titles and abstracts and reviewed full texts, with discrepancies resolved by a third reviewer. We used the Mixed Methods Appraisal Tool for quality appraisal and narrative synthesis to identify key findings. We also conducted stakeholder consultation (Patient and Public Involvement (PPI)) with nine children, where they submitted annotated drawings of their preferred masks to complement our review findings.

RESULTS

We screened 982 titles and abstracts and reviewed 94 full texts. 45 studies were included in the synthesis. Children's experiences of mask-wearing were influenced by their perceived necessity, social norms around their use and parental attitudes. Challenges related to mask-wearing were described, including difficulty reading facial expressions and physical discomfort. Children found it easier to wear masks when sitting and in cooler environments, and they benefited from unmasking during outdoor break time at school. As part of the PPI consultation, children highlighted the importance of mask design and the environmental impact of masks.

CONCLUSION

Children's experiences of mask-wearing were varied and context-dependent, with several mask-design challenges raised. Future policy on mask-wearing needs to consider the context in which mask-wearing would be most beneficial, and how local adaptations to policy can respond to children's needs.

An antimicrobial zinc ion fiber for COVID-19 prevention in nonwoven face coverings for healthcare settings

The COVID-19 pandemic created an unprecedented increase in the usage of personal protective equipment (PPE) in the healthcare industry, especially in the form of face coverings. Subsequently, guidelines related to breathability and wear comfort were published by the Centers for Disease Control (CDC) as an influx of various new materials entered the PPE market. This study evaluated a proprietary, novel, zinc-ion embedded fiber with the ability to deactivate bacteria and viruses, including SARS-COV-2, for its wear comfort in a nonwoven disposable mask in comparison to a commercially available surgical face mask which served as the control. Ten healthy, full-time, career, firefighters participated in this study wearing both masks in a randomized fashion. A medical task simulation (MTS) protocol was developed to replicate nursing task metabolic rates, per the compendium of physical activities, via a graded treadmill walking exercise. Participant ratings including ease of mask fit, overall mask comfort, facial comfort, breathability, and facial temperature sensation were recorded before, during, and after the 50-minute protocol in a controlled environmental chamber. The 100% nylon, zinc ion mask was rated as slightly cooler at the beginning of the trial (at 0.8 vs. 1.3), than the commercially available polypropylene mask. The polypropylene mask also reached a perceived mask facial comfort (MFC) rating of 1.6 just 35 min into the protocol whereas the zinc ion mask did not reach a rating of slight discomfort until the end of the exercise. Findings indicate the novel zinc-ion embedded mask was as comfortable, if not more so, than the commercially available nonwoven mask with more favorable ratings for longer durations. Not only do the zinc properties provide enhanced protection, but they maintain, if not improve, wearer comfort.

Health effects of filtering facepiece respirators: Research and clinical implications of comfort, thermal, skin, psychologic, and workplace effects

Filtering facepiece respirators (FFR's) such as N95s have become widely used in appropriate settings for personal respiratory protection and are increasingly used beyond workplace settings. Concerns about possible adverse effects have appeared in many publications, particularly since the COVID-19 pandemic led to much more widespread use. This paper synthesizes known effects based upon review of publications in PubMed since 1995, addressing effects other than pulmonary and cardiovascular (reviewed elsewhere). Findings: (1) Subjective discomfort is very frequently reported; this includes general discomfort or organ-system-specific complaints such as respiratory, headache, dermatologic, and heat. Research methods are widely divergent, and we propose a taxonomy to classify such studies by methodology, study population (subjects, experimental vs. observational methodology, comparator, specificity, and timeframe) to facilitate synthesis. (2) Objective measures of increased heat and humidity within the mask are well documented. (3) Frequency and characteristics of dermatologic effects have been insufficiently evaluated. (4) Physical mask designs are varied, making generalizations challenging. (5) More studies of impact on work performance and communication are needed. (6) Studies of effect of FFR design and accompanying training materials on ease and consistency of use are needed.

A systematic review of passing fit testing of the masks and respirators used during the COVID-19 pandemic: Part 1-quantitative fit test procedures

BACKGROUND

During respiratory infection pandemics, masks and respirators are highly sought after, especially for frontline healthcare workers and patients carrying respiratory viruses. The objective of this study was to systematically review fit test pass rates and identify factors influencing the fitting characteristics.

METHODS

Potentially relevant studies were identified using PubMed, Scopus, Web of Science, and Science Direct during the COVID-19 pandemic from February 5, 2020, to March 21, 2023. The search strategy using the following keywords was conducted: Quantitative Fit Test, Condensation Nuclei Counter, Controlled Negative Pressure, PortaCount, Sibata, Accufit, Fit, Seal, Mask, Respirator, Respiratory Protective Device, Respiratory Protective Equipment, Protective Device, Personal Protective Equipment, COVID-19, Coronavirus, and SARS-CoV-2. The quality of the included studies was also assessed using the Newcastle-Ottawa scale.

RESULTS

A total of 137 articles met the eligibility criteria. Fifty articles had a quality score of less than 7 (good quality). A total of 21 studies had a fit test pass rate of less than 50%. 26 studies on disposable respirators and 11 studies on reusable respirators had an FF of less than 50 and less than 200, respectively. The most influential factors include respirator brand/model, style, gender, ethnicity, facial dimensions, facial hair, age, reuse, extensive movement, seal check, comfort and usability assessment, and training.

CONCLUSION

37.36% of the disposable respirator studies and 43% of the reusable respirator studies did not report fit test results. 67.86% of the disposable respirator studies had a fit test pass rate greater than 50%, and 35.84% of these studies had an FF greater than 100. Also, 85.71% of the reusable respirator studies had a fit test pass rate greater than 50%, and 52.77% of these studies had an FF greater than 1000. Overall, the fit test pass rate was relatively acceptable. Newly developed or modified respirators must undergo reliable testing to ensure the protection of HCWs. Subject and respirator characteristics should be considered when implementing fit testing protocols. An optimal fit test panel should be developed prior to respirator design, certification, procurement decisions, and selection procedures.

Physiologic effects of surgical masking in children versus adults

Background

Surgical masks remain a focal part of the CDC guidelines to decrease COVID-19 transmission. Evidence refuting significant effects of masking on ventilation is mostly limited to small studies, with a paucity of studies on children, and none comparing children to adults.

Methods

A total of 119 subjects were enrolled (71 adults, 49 children) in a prospective interventional study with each subject serving as their own mask-free control. End tidal CO2 (ETCO2), inspired CO2 (ICO2), and respiratory rate were measured by nasal cannula attached to an anesthesia machine D-fend module. Pulse oximetry and heart rate were also followed. After the mask-free period, an ASTM Level 3 disposable surgical mask was donned and 15 min of mask-worn data were collected.

Results

A steady state was confirmed for ETCO2 and ICO2 over the masked period, and mean ICO2 levels rose significantly (p < 0.001) after masking in all age groups. The increase in ICO2 for the 2- to 7-year-old group of 4.11 mmHg (3.23-4.99), was significantly higher (p < 0.001) than the final ΔICO2 levels for both the 7- to 14-year-old group, 2.45 mmHg (1.79-3.12), and adults, 1.47 mmHg (1.18-1.76). For the pediatric group there was a negative, significant correlation between age and ΔICO2, r = -0.49, p < 0.001. Masking resulted in a statistically significant (p < 0.01) rise in ETCO2 levels of 1.30 mmHg in adults and 1.36 mmHg in children. The final respective ETCO2 levels, 34.35 (33.55-35.15) and 35.07 (34.13-36.01), remained within normal limits. Pulse oximetry, heart rate, and respiratory rate were not significantly affected.

Discussion

The physiology of mechanical dead space is discussed, including the inverse relationship of subject age vs ICO2. The methodology and results are compared to previously published studies which detracted from the physiologic safety of surgical masking.

Conclusions

The wearing of a surgical mask results in a statistically significant rise in ICO2 and a smaller rise in ETCO2. Because ETCO2 and other variables remain well within normal limits, these changes are clinically insignificant.

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 &lt; 0.001) and minute ventilation (SMD = −0.72, 95% CI = −0.99 to −0.46, p &lt; 0.001), simultaneous increased in blood-CO2 (SMD = +0.64, 95% CI = 0.31–0.96, p &lt; 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 &lt; 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 &lt; 0.006 to p &lt; 0.001). Pooled symptom prevalence (n = 8,128) was significant for: headache (62%, p &lt; 0.001), acne (38%, p &lt; 0.001), skin irritation (36%, p &lt; 0.001), dyspnoea (33%, p &lt; 0.001), heat (26%, p &lt; 0.001), itching (26%, p &lt; 0.001), voice disorder (23%, p &lt; 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.

Personal strategies to mitigate the effects of air pollution exposure during sport and exercise: a narrative review and position statement by the Canadian Academy of Sport and Exercise Medicine and the Canadian Society for Exercise Physiology

Air pollution is among the leading environmental threats to health around the world today, particularly in the context of sports and exercise. With the effects of air pollution, pollution episodes (eg, wildfire conflagrations) and climate change becoming increasingly apparent to the general population, so have their impacts on sport and exercise. As such, there has been growing interest in the sporting community (ie, athletes, coaches, and sports science and medicine team members) in practical personal-level actions to reduce the exposure to and risk of air pollution. Limited evidence suggests the following strategies may be employed: minimising all exposures by time and distance, monitoring air pollution conditions for locations of interest, limiting outdoor exercise, using acclimation protocols, wearing N95 face masks and using antioxidant supplementation. The overarching purpose of this position statement by the Canadian Academy of Sport and Exercise Medicine and the Canadian Society for Exercise Physiology is to detail the current state of evidence and provide recommendations on implementing these personal strategies in preventing and mitigating the adverse health and performance effects of air pollution exposure during exercise while recognising the limited evidence base.

The physiological, perceptual, and thermoregulatory responses to facemask use during exercise

The use of masks in public settings and when around people has been recommended to limit the spread of Coronavirus disease 2019 (COVID-19) by major public health agencies. Several different types of masks classified as either medical- or non-medical grade are commonly used among the public. However, concerns with difficulty breathing, re-breathing exhaled carbon dioxide, a decrease in arterial oxygen saturation, and a decrease in exercise performance have been raised regarding the use of mask during exercise. We review the current knowledge related to the effect of different masks during exercise on cardiorespiratory, metabolic, thermoregulatory, and perceptual responses. As such, the current literature seems to suggest that there are minimal changes to cardiovascular, metabolic, and no changes to thermoregulatory parameters with facemask use. However, differences in ventilatory parameters have been reported with submaximal and maximal intensity exercise to volitional fatigue. Literature on perceptual responses to exercise indicate an impact on ratings of perceived exertion, dyspnea, and overall discomfort dependent on mask use as well as exercise intensity. In conclusion, data from the current literature suggests a minimal impact on physiological, perceptual, and thermoregulatory responses dependent on the type of mask used during exercise.

Effects of Wearing a Mask During Exercise on Physiological and Psychological Outcomes in Healthy Individuals: A Systematic Review and Meta-Analysis

BACKGROUND

Wearing face masks in public is an effective strategy for preventing the spread of viruses; however, it may negatively affect exercise responses. Therefore, this review aimed to explore the effects of wearing different types of face masks during exercise on various physiological and psychological outcomes in healthy individuals.

METHODS

A literature search was conducted using relevant electronic databases, including Medline, PubMed, Embase, SPORTDiscus, Web of Science, and Cochrane Central Register of Controlled Trials on April 05, 2022. Studies examining the effect of mask wearing (surgical mask, cloth mask, and FFP2/N95 respirator) during exercise on various physiological and psychological parameters in apparently healthy individuals were included. For meta-analysis, a random effects model was used. Mean difference (MD) or standardized MD (SMD) with 95% confidence intervals (CI) were calculated to analyze the total effect and the effect in subgroups classified based on face mask and exercise types. The quality of included studies was examined using the revised Cochrane risk-of-bias tool.

RESULTS

Forty-five studies with 1264 participants (708 men) were included in the systematic review. Face masks had significant effects on gas exchange when worn during exercise; this included differences in oxygen uptake (SMD - 0.66, 95% CI - 0.87 to - 0.45), end-tidal partial pressure of oxygen (MD - 3.79 mmHg, 95% CI - 5.46 to - 2.12), carbon dioxide production (SMD - 0.77, 95% CI - 1.15 to - 0.39), and end-tidal partial pressure of carbon dioxide (MD 2.93 mmHg, 95% CI 2.01-3.86). While oxygen saturation (MD - 0.48%, 95% CI - 0.71 to - 0.26) decreased slightly, heart rate was not affected. Mask wearing led to higher degrees of rating of perceived exertion, dyspnea, fatigue, and thermal sensation. Moreover, a small effect on exercise performance was observed in individuals wearing FFP2/N95 respirators (SMD - 0.42, 95% CI - 0.76 to - 0.08) and total effect (SMD - 0.23, 95% CI - 0.41 to - 0.04).

CONCLUSION

Wearing face masks during exercise modestly affected both physiological and psychological parameters, including gas exchange, pulmonary function, and subjective discomfort in healthy individuals, although the overall effect on exercise performance appeared to be small. This review provides updated information on optimizing exercise recommendations for the public during the COVID-19 pandemic.

SYSTEMATIC REVIEW REGISTRATION NUMBER

This study was registered in the International Prospective Register of Systematic Review (PROSPERO) database (registration number: CRD42021287278).

The influence of N95 and FFP2 masks on cardiorespiratory variables in healthy individuals during aerobic exercise: a systematic review and meta-analysis

OBJECTIVE

In view of the current COVID-19 pandemic, the objective of this study was to determine, through a systematic review and meta-analysis, whether the use of N95/FFP2 masks during aerobic exercise has a significant impact on HR, RR, SpO2, and blood pressure (BP) in healthy individuals.

METHODS

We searched the MEDLINE database for studies published in English between 2005 and 2021. To reduce bias and increase reliability, only randomized controlled trials and randomized crossover clinical trials were considered for inclusion. The selected outcomes included HR, RR, SpO2, and BP, with perceived exertion being evaluated by means of the Borg scale.

RESULTS

Eight controlled trials were included in the meta-analysis. Seven evaluated HR (p > 0.05), five evaluated RR (p > 0.05), five evaluated SpO2 and BP (p > 0.05 for both), and six evaluated perceived exertion, presenting controversial results such as risk ratios that were grouped for each variable.

CONCLUSIONS

This study suggests that N95 and FFP2 masks do not have significant effects on HR, RR, SpO2, and BP during aerobic exercise in healthy individuals.

Patient safety implications of wearing a face mask for prevention in the era of COVID-19 pandemic: a systematic review and consensus recommendations

In the past, the use of face masks in western countries was essentially limited to occupational health. Now, because of the COVID-19 pandemic, mask-wearing has been recommended as a public health intervention. As potential side effects and some contraindications are emerging, we reviewed the literature to assess the impact of them in daily life on patient safety and to provide appropriate guidelines and recommendations. We performed a systematic review of studies investigating physiological impact, safety, and risk of masks in predefined categories of patients, which have been published in peer-reviewed journals with no time and language restrictions. Given the heterogeneity of studies, results were analyzed thematically. We used PRISMA guidelines to report our findings. Wearing a N95 respirator is more associated with worse side effects than wearing a surgical mask with the following complications: breathing difficulties (reduced FiO₂, SpO₂^, PaO₂ increased ETCO₂, PaCO₂), psychiatric symptoms (panic attacks, anxiety) and skin reactions. These complications are related to the duration of use and/or disease severity. Difficulties in communication is another issue to be considered especially with young children, older person and people with hearing impairments. Even if benefits of wearing face masks exceed the discomfort, it is recommended to take an "air break" after 1-2 h consecutively of mask-wearing. However, well-designed prospective studies are needed. The COVID-19 pandemic could represent a unique opportunity for collecting large amount of real-world data.

The Difference in Electromyographic Activity While Wearing a Medical Mask in Women with and without Temporomandibular Disorders

Wearing a medical mask influences resting activity of the temporalis anterior and masseter muscles in healthy young women. However, no studies link medical mask-wearing with masticatory muscle activity in patients with temporomandibular disorders (TMDs). Therefore, this study aims to compare electromyographic patterns while wearing a medical mask between women with and without temporomandibular disorders. Based on the Research Diagnostic Criteria for Temporomandibular Disorders, 115 adult women qualified for the study. Participants were divided into the following two groups: diagnosed TMDs (n = 55; mean age: 23.5 ± 2.3 years) and healthy women (n = 60; mean age: 23.7 ± 2.6 years). Examinations of the resting and functional electromyographic activity of the temporalis anterior (TA), superficial masseter (MM), anterior bellies of the digastric muscle (DA), and the middle part of the sternocleidomastoid muscle (SCM) were carried out using the BioEMG III™. Both groups showed statistically significant decreases in resting masticatory muscle activity during medical mask examination compared to no mask measurement. The significant differences in no mask measurement between both groups were noted regarding resting masticatory activity, clenching in the intercuspal position, and clenching on dental cotton rollers. During medical mask examination, women with TMDs showed differences in resting masticatory activity and clenching on dental cotton rollers compared to the healthy group. In all analyzed variables, both groups showed similar electromyographic patterns in the maximum mouth opening measurement during medical mask and no mask examination. A medical mask influences the resting bioelectric activity of the masticatory muscles in women with temporomandibular disorders and healthy women. We observed differences and some similarities in resting and functional electromyographic patterns within masticatory and neck muscles in both groups during medical mask and no mask examination.

Investigation of the Thermal Comfort Properties of Masks Used during the COVID-19 Pandemic

SARS-CoV-2, the causative agent of COVID-19, which was officially declared a pandemic by the World Health Organization (WHO) on 11 March 2020, is transmitted from person to person through respiratory droplets and close contact and can cause severe respiratory failure and pneumonia. Currently, while the worldwide COVID-19 pandemic is still ongoing and countries are taking strict precautions to protect populations against infection, the most effective precautions still seem to be social distancing and wearing a mask. The question of how effective masks were in the early stages of the COVID-19 pandemic has been widely discussed, both in public and scientific circles, and the protection of different mask types has been examined. This study aimed to examine the comfort conditions provided by the different mask types to the user during use. For this purpose, single-ply, double-ply, three-ply, cloth, FFP1, FFP2, and FFP3 masks with different standards were examined, with and without a valve. To conduct the experiments, the novel thermal head measurement system, developed within the scope of this study, was used specifically for mask comfort studies. Thanks to the developed measurement system, the thermal resistance and water vapor resistance values of different masks were measured, and their comfort conditions were evaluated. According to the findings, cloth masks provide a comfortable condition, with lower thermal resistance and water vapor resistance values than other masks. In addition, it was observed that surgical masks offer better thermal comfort conditions, although they have lower protection than FFP masks.

Carbon dioxide rises beyond acceptable safety levels in children under nose and mouth covering: Results of an experimental measurement study in healthy children

Nose and mouth covering (NMC) has been made compulsory for children in many countries during the Covid-19 pandemic. We wanted to determine the average CO₂ levels in inhaled air with NMC in children between age 6 and 17. We used short term measurements under surgical masks and FFP2 masks according to European norm EN 149, compared to baseline in an experimental, intra-individually controlled study over 25 min. CO₂ content was measured every 15 s using an automated dual-wavelength infrared CO₂ measurement device (G100, Geotech, Leamington Spa, UK) over 25 min in a short-term experimental setting, with children seated. After baseline measurement children were provided with two types of commonly worn NMC: surgical masks and FFP2--masks in randomized sequence for 3 min each. We kept ambient CO₂-levels below 1000 parts per million (ppm) through frequent ventilation. We measured breathing frequency and pulse as potential physiological moderator variables. Forty-five children, 25 boys, 20 girls, with a mean age of 10.7 years (standard deviation 2.6) were measured. We measured 13,100 ppm (SD 380) under surgical mask and 13,900 ppm (SD 370) under FFP2 mask in inhaled air. A linear model with age as a covariate showed a highly significant effect of the condition (p < 1*10^-9). We measured 2,700 ppm (SD 100) CO₂ at pre-baseline and 2,800 ppm (SD 100) at post-baseline, a non-significant small difference. Appropriate contrasts revealed that the change was due to the masks only and the difference between the two types of masks was small and not significant. Wearing of NMC (surgical masks or FFP2- -masks) raises CO₂ content in inhaled air quickly to a very high level in healthy children in a seated resting position that might be hazardous to children's health.

Mask Use for Athletes: A Systematic Review of Safety and Performance Outcomes

CONTEXT

With the current Centers for Disease Control and Prevention recommendations for mask use to minimize transmission of coronavirus 2019 (COVID-19) coupled with concern for future pandemics that would require mask wearing, providing data-driven guidance with respect to athletic performance is essential.

OBJECTIVE

The purpose of this study was to perform a systematic review of existing literature on the use of face masks while exercising to assess the physiologic effects of face masks worn during athletic activities.

DATA SOURCES

A systematic review was conducted of studies on face mask use during exercise according to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Potential studies were identified through searches of MEDLINE, Embase, Cochrane CENTRAL and CINAHL databases.

STUDY SELECTION

Screening was completed independently by 2 coauthors who sought to identify studies that described the effects of oronasal mask use, if any, on sports/exercise/physical activity, for any age, gender, or level of sport. Articles describing mask effects without exercise, articles published before 1980, and non-English language studies were excluded.

STUDY DESIGN

Systematic review.

LEVEL OF EVIDENCE

Level 3.

DATA EXTRACTION

Data extraction focused on physiologic parameters measured during physical activity performed while wearing a face mask.

RESULTS

Twenty-two articles met all inclusion criteria. Study analysis revealed that the use of masks in healthy volunteers during exercise had no significant effect on physiologic parameters measured including heart rate (HR), respiratory rate (RR), oxygen saturation, and perceived exertion. Of the studies that investigated N95 masks in the healthy adult population, 2 reported modest changes in RR and maximum power output indicative of decreased athletic performance when subjects were exercising at maximum effort. Similar findings were seen in studies of subpopulations including children and pregnant women.

CONCLUSION

Available data suggest that healthy individuals can perform moderate-to-vigorous exercise while wearing a face mask without experiencing changes in HR, RR, and oxygen saturation that would compromise individual safety or athletic performance. In the specific situation in which an N95 mask is worn, maximum power generated may be impaired.

WHAT IS KNOWN ABOUT THE SUBJECT

To date, there has been no systematic review of the existing literature to provide a clear consensus on whether face mask use significantly impacts athletic performance. Mask use has been demonstrated safe in the workplace; however, the use of face masks during exercise has not been examined on a large scale, particularly with respect to physiologic parameters.

WHAT THIS STUDY ADDS TO EXISTING KNOWLEDGE

This analysis highlights that available data suggest that healthy individuals can perform heavy exercise in face masks with minimal physiologic changes. This is the first systematic review of studies analyzing exercise use wearing masks. With the evidence presented here commonly cited concerns about both safety and performance decrements with mask use during physical activities may be allayed.

[Interdisciplinary Perspectives on the Role of Aerosol Transmission in SARS-CoV-2 Infections]

The relevance of aerosols for the transmission of the Severe Acute Respiratory Syndrome Coronavirus Type 2 (SARS-CoV-2) is still debated. However, over time, in addition to distancing and hygiene rules, aerosol physics-based measures such as wearing face masks and ventilating indoor spaces were found to be efficient in reducing infections. In an interdisciplinary workshop "Aerosol & SARS-CoV-2" of the Association for Aerosol Research (GAeF) in cooperation with the German Society for Pneumology and Respiratory Medicine (DGP), the Professional Association of General Air Technology of the VDMA, the German Society for Virology (GfV), the Health Technology Society (GG) and the International Society for Aerosols in Medicine (ISAM) under the auspices of the Robert Koch Institute (RKI) in March 2021, the need for research and coordination on this topic was addressed. Fundamental findings from the various disciplines as well as interdisciplinary perspectives on aerosol transmission of SARS-CoV-2 and infection mitigation measures are summarized here. Finally, open research questions and needs are presented.

Effectiveness of a 3D-printed mask fitter in an Ophthalmology setting during COVID-19

OBJECTIVE

To assess the effectiveness of a 3D-printed custom mask fitter in lieu of N95 respirators among ophthalmologists and other eye care professionals who may not be prioritized to receive N95 respirators amidst the coronavirus disease 2019 pandemic.

METHODS

This was a proof-of-concept study from a tertiary eye care center in Oakville, Canada. All participants underwent the N95 Qualitative Fit Test with a custom mask fitter secured over an American Society for Testing and Materials Level 3 face mask. Participants answered a 10-point Likert scale questionnaire on comfort, ease of use, and feasibility of the custom mask fitter, as well as comfort of a regular face mask.

RESULTS

Twenty participants were recruited. Of the 20 recruited, 18 (90%) successfully passed the fit test. The median scores for comfort, ease of use, and everyday feasibility for the custom mask fitter were 3.5, 4.5, and 3, respectively, whereas the median score for comfort of a regular face mask was 8.5.

CONCLUSION

A reusable, low-cost, 3D-printed custom mask fitter is a potential effective alternative to an N95 respirator among eye care professionals but may require improvement in its design and comfort. This is especially relevant in the context of a limited supply of N95 respirators amidst a global pandemic.

The Physiological Effects of Face Masks During Exercise Worn Due to COVID-19: A Systematic Review

CONTEXT

Use of facemasks in sport has been a particularly complex issue during the COVID-19 pandemic.

OBJECTIVES

A systematic review to examine the physiological effects the different types of masks have on healthy adults when doing physical exercise.

DATA SOURCES

PubMed, SPORTDiscus, Scopus, and Litcovid were searched up to March 20, 2021, following the PRISMA model. Articles published in the last 5 years with healthy adults.

STUDY SELECTION

A total of 633 studies related to the use of masks during physical exercise were found, of which 8 articles met the criteria to be included.

STUDY DESIGN

Systematic review.

LEVEL OF EVIDENCE

Level 2.

DATA EXTRACTION

The search process and the review of the articles were carried out by independent expert researchers. The risk of bias and the methodological quality of the different studies included in the systematic review were calculated following the Cochrane criteria using an adaptation for random cross-studies. Once the information was properly structured, the results were extracted, and the findings of the study analyzed.

RESULTS

There were significant changes in the following physiological variables when engaging in physical exercise using masks: 25% in the heart rate and dyspnea, 37.5% in the rating of perceived exertion, 50% in the pulmonary variables, and 37.5% in discomfort. The oxygen saturation, blood pressure, systolic blood pressure, diastolic blood pressure, and the concentration of blood lactate did not present any significant effect in this study.

CONCLUSIONS

The usage of masks by a healthy adult population during the performance of physical exercise has shown minimal effects with regard to physiological, cardiorespiratory, and perceived responses. Some symptoms can be dyspnea, effort perceived, or discomfort, among others. These findings indicate that the use of masks is not harmful to individuals' health. It does not present any significant detrimental effect on physical performance or risk to their well-being. However, further experiments are required to corroborate the findings of this review.

The Cardiopulmonary Effects of Medical Masks and Filtering Facepiece Respirators on Healthy Health Care Workers in the Emergency Department: A Prospective Cohort Study

Background

International COVID-19 guidelines recommend that health care workers (HCWs) wear filtering facepiece (FFP) respirators to reduce exposure risk. However, there are concerns about FFP respirators causing hypercapnia via rebreathing carbon dioxide (CO₂). Most previous studies measured the physiological effects of FFP respirators on treadmills or while resting, and such measurements may not reflect the physiological changes of HCWs working in the emergency department (ED).

Objective

Our aim was to evaluate the physiological and clinical impacts of FFP type II (FFP2) respirators on HCWs during 2 h of their day shift in the ED.

Methods

We included emergency HCWs in this prospective cohort study. We measured end-tidal CO₂ (ETCO₂), mean arterial pressure (MAP), respiratory rate (RR), and heart rate values and dyspnea scores of subjects at two time points. The first measurements were carried out with medical masks while resting. Subjects then began their day shift in the ED with medical mask plus FFP2 respirator. We called subjects after 2 h for the second measurement.

Results

The median age of 153 healthy volunteers was 24.0 years (interquartile range 24.0–25.0 years). Subjects’ MAP, RR, and ETCO₂ values and dyspnea scores were significantly higher after 2 h. Median ETCO₂ values increased from 36.4 to 38.8 mm Hg. None of the subjects had hypercapnia symptoms, hypoxia, or other adverse effects.

Conclusion

We did not observe any clinical reflection of these changes in physiological values. Thus, we evaluated these changes to be clinically insignificant. We found that it is safe for healthy HCWs to wear medical masks plus FFP2 respirators during a 2-h working shift in the ED.

Bayesian network meta-analysis of face masks' impact on human physiology

Several concerns regarding the safety of face masks use have been propounded in public opinion. The objective of this review is to examine if these concerns find support in the literature by providing a comprehensive overview of physiological responses to the use of face masks. We have performed a systematic review, pairwise and network meta-analyses to investigate physiological responses to the use of face masks. The study has been registered with PROSPERO (C RD42020224791). Obtained results were screened using our exclusion and inclusion criteria. Meta-analyses were performed using the GeMTC and meta R packages. We have identified 26 studies meeting our inclusion and exclusion criteria, encompassing 751 participants. The use of face masks was not associated with significant changes in pulsoxymetrically measured oxygen saturation, even during maximal-effort exercises. The only significant physiological responses to the use of face masks during low-intensity activities were a slight increase in heart rate, mildly elevated partial pressure of carbon dioxide (not meeting criteria for hypercarbia), increased temperature of facial skin covered by the mask, and subsequent increase of the score in the rating of heat perception, with N95 filtering facepiece respirators having a greater effect than surgical masks. In high-intensity conditions, the use of face masks was associated with decreased oxygen uptake, ventilation, and RR. Face masks are safe to use and do not cause significant alterations in human physiology. The increase in heart rate stems most likely from increased respiratory work required to overcome breathing resistance. The increase in carbon dioxide is too small to be clinically relevant. An increased rating of heat perception when using face masks results from higher temperature of facial skin covered by the mask.

Effectiveness of N95 Masks against SARS-CoV-2: Performance Efficiency, Concerns, and Future Directions

The coronavirus disease 2019 (COVID-19) epidemic, which is caused by novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has continued to spread around the world since December 2019. Healthcare workers and other medical first responders in particular need personal protective equipment to protect their respiratory system from airborne particulates, in addition to liquid splashes to the face. N95 respirator have become a critical component for reducing SARS-CoV-2 transmission and controlling the scale of the COVID-19 pandemic. However, a major dispute concerning the protective performance of N95 respirators has erupted, with a myriad of healthcare workers affected despite wearing N95 masks. This article reviews the most recent updates about the performance of N95 respirators in protecting against the SARS-CoV-2 virus in the present pandemic situation. A brief overview of the manufacturing methods, air filtration mechanisms, stability, and reusability of the mask is provided. A detailed performance evaluation of the mask is studied from an engineering point of view. This Review also reports on a comparative study about the protective performance of all commercially available surgical and respiratory masks used to combat the spread of COVID-19. With the aim of protecting healthcare providers more efficiently, we suggest some potential directions for the development of this respiratory mask that improve the performance efficiency of the mask.

Investigating the Effects of Protective Face Masks on the Respiratory Parameters of Children in the Postanesthesia Care Unit During the COVID-19 Pandemic

PURPOSE

The purpose of this study was to investigate the effect of protective face mask usage during the postoperative period on carbon dioxide retention in children during the COVID-19 pandemic.

DESIGN

This study was designed as a prospective, randomized trial including 40 ASA I-II patients aged 3 to 10 years who were scheduled for elective surgery.

METHODS

Patients were randomly allocated to two groups. The first group (group 1) received O₂ treatment over the protective face mask. In the second group (group 2), the protective face mask was worn over the O₂ delivery system. Heart rate, oxygen saturation (SPO₂) level, end-tidal carbon dioxide (EtCO₂) level, and respiratory rate were measured using a patient monitor at 0, 5, 10, 15, 30, and 45 minutes and recorded. The primary outcome of the study was the determination of the EtCO₂ levels, which were used to assess the safety of the mask in terms of potential carbon dioxide retention.

FINDINGS

None of the participants' SPO₂ levels fell below 92% while wearing masks. There was no statistically significant difference between the groups in terms of EtCO₂, heart rate, SPO₂, and respiratory rate (P > .05).

CONCLUSIONS

During the COVID-19 pandemic, protective surgical face masks can be used safely in the postoperative period for pediatric patients aged 3 to 10 years.

To Mask or Not to Mask—Evaluation of Cognitive Performance in Children Wearing Face Masks during School Lessons (MasKids)

In the current SARS-CoV-2 pandemic, wearing a face mask is mandatory again during school lessons. There are no controlled studies in children to date indicating an effect on cognitive performance from wearing face masks. In a randomized controlled trial, we analysed the influence of face masks on cognitive performance of pupils during regular school lessons. Pupils (n = 133, fifth to seventh grade) were randomized by alternating allocation into control (with masks, n = 65) and intervention groups (without mask, n = 68). After two school lessons with (control) and without (intervention) face masks in class, all pupils performed digital tests for cognitive performance regarding attention and executive functions (switch, Corsi block-tapping, 2-back and flanker task). Overall, there were no significant differences in cognitive performance between both groups, masks vs. no masks. Wearing face masks has no significant influence on attention and executive functions of pupils and can still be recommended during school lessons.

Smart facemask for wireless CO2 monitoring

The use of facemasks by the general population is recommended worldwide to prevent the spread of SARS-CoV-2. Despite the evidence in favour of facemasks to reduce community transmission, there is also agreement on the potential adverse effects of their prolonged usage, mainly caused by CO2 rebreathing. Herein we report the development of a sensing platform for gaseous CO2 real-time determination inside FFP2 facemasks. The system consists of an opto-chemical sensor combined with a flexible, battery-less, near-field-enabled tag with resolution and limit of detection of 103 and 140 ppm respectively, and sensor lifetime of 8 h, which is comparable with recommended FFP2 facemask usage times. We include a custom smartphone application for wireless powering, data processing, alert management, results displaying and sharing. Through performance tests during daily activity and exercise monitoring, we demonstrate its utility for non-invasive, wearable health assessment and its potential applicability for preclinical research and diagnostics.

Development and validation of the discomfort of cloth Masks-12 (DCM-12) scale

During the COVID-19 pandemic, the use of face masks by the public has helped to slow the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the community. Cloth masks have been recommended because of their effectiveness, availability, and reusability. Like other types of face masks, however, user discomfort while wearing cloth masks is thought to engender behaviors that limit the effectiveness of cloth masks as source control (e.g., adjusting or removing one's mask temporarily while in public). To design cloth masks that are more tolerable, a measurement instrument for assessing subjective user discomfort is needed. Across two studies, we identified and confirmed a two-dimensional factor structure underlying the discomfort of cloth masks - discomfort related to the breathability and discomfort related to the tightness of the mask against the face and head. Additionally, we provide replicable evidence that both factor-subscales predict the self-reported frequencies of problematic mask-wearing behaviors.

Personal Interventions to Reduce Exposure to Outdoor Air Pollution

Unhealthy levels of air pollution are breathed by billions of people worldwide, and air pollution is the leading environmental cause of death and disability globally. Efforts to reduce air pollution at its many sources have had limited success, and in many areas of the world, poor air quality continues to worsen. Personal interventions to reduce exposure to air pollution include avoiding sources, staying indoors, filtering indoor air, using face masks, and limiting physical activity when and where air pollution levels are elevated. The effectiveness of these interventions varies widely with circumstances and conditions of use. Compared with upstream reduction or control of emissions, personal interventions place burdens and risk of adverse unintended consequences on individuals. We review evidence regarding the balance of benefits and potential harms of personal interventions for reducing exposure to outdoor air pollution, which merit careful consideration before making public health recommendations with regard to who should use personal interventions and where, when, and how they should be used. Expected final online publication date for the Annual Review of Public Health, Volume 43 is April 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

What We Are Learning from COVID-19 for Respiratory Protection: Contemporary and Emerging Issues

Infectious respiratory diseases such as the current COVID-19 have caused public health crises and interfered with social activity. Given the complexity of these novel infectious diseases, their dynamic nature, along with rapid changes in social and occupational environments, technology, and means of interpersonal interaction, respiratory protective devices (RPDs) play a crucial role in controlling infection, particularly for viruses like SARS-CoV-2 that have a high transmission rate, strong viability, multiple infection routes and mechanisms, and emerging new variants that could reduce the efficacy of existing vaccines. Evidence of asymptomatic and pre-symptomatic transmissions further highlights the importance of a universal adoption of RPDs. RPDs have substantially improved over the past 100 years due to advances in technology, materials, and medical knowledge. However, several issues still need to be addressed such as engineering performance, comfort, testing standards, compliance monitoring, and regulations, especially considering the recent emergence of pathogens with novel transmission characteristics. In this review, we summarize existing knowledge and understanding on respiratory infectious diseases and their protection, discuss the emerging issues that influence the resulting protective and comfort performance of the RPDs, and provide insights in the identified knowledge gaps and future directions with diverse perspectives.

Assessment of respiratory function in children wearing a N95 mask with or without an exhalation valve: Data compared

In response to the current COVID-19 pandemic, universal face masking represents one of the most important strategies to limit the spread of infection. However, their use in children is still highly debated (Esposito and Principi, 2020; Esposito et al., 2020) and there are few data (Lubrano et al., 2021a, 2021b) describing their possible effects on respiratory function in children. A dataset in this paper presents a comparison of the data related to the effects on respiratory function of children wearing a filtering facepiece 2 (N95 mask) with or without exhalation valve. 22 healthy children were randomly assigned to two groups, both groups wearing an N95 mask: one without an exhalation valve (group A), another with an exhalation valve (group B). Children were subjected to a 72 min test: the first 30 min without mask, then 30 min wearing face mask while practiced their usual play activity; finally, 12 min, with face mask in place, while they walked as in a walking test. They were monitored through to microstream capnography system (Rad-97TM with Nomo-Line Capnography, Masimo, Irvine, CA, USA) to log oxygen saturation (SpO2) and respiratory rate (RR). We use the Wilcoxon test to analyzed the differences between the parameters recorded during the study in group A and B. Data analysis was performed using JMP14.3.0 program for Mac by SAS Institute inc.

Wearing a Surgical Face Mask Has Minimal Effect on Performance and Physiological Measures during High-Intensity Exercise in Youth Ice-Hockey Players: A Randomized Cross-Over Trial

COVID-19 transmission is prevalent during ice-hockey; however, it is unknown whether wearing face masks as a mitigation strategy affects hockey players’ performance. We used a randomized cross-over study to compare wearing a surgical mask to a sham mask (control) in youth hockey players (21 males, 5 females, 11.7 ± 1.6 y) during a simulated hockey period (cycle ergometry; six shifts of 20 s of “easy” pedaling (40% peak power), 10 s of “hard” pedaling (95% peak power), 20 s of “easy” pedaling, with shifts separated by 5 min rests). A seventh shift involved two 20 s Wingate tests separated by 40 s rest. Heart rate, arterial oxygen saturation and vastus lateralis tissue oxygenation index (hemoglobin saturation/desaturation) was assessed each shift. On-ice testing was conducted with the maximal Yo-Yo intermittent recovery test. No differences between mask and control conditions for performance were found (Wingate average power: 245 ± 93 vs. 237 ± 93 W, Peak power: 314 ± 116 vs. 304 ± 115 W, on-ice distance: 274 ± 116 vs. 274 ± 110 m) and for heart rate or arterial oxygen saturation during simulated hockey shifts. Tissue oxygenation index was lower from shifts one to six for males (p < 0.05) and shift seven for females (p < 0.01) while wearing a mask. Wearing a face mask had no effect on performance in hockey players with only minor effects on muscle oxygenation. ClinicalTrials.gov (NCT04874766) (accessed on 6 May 2021).

Effect of Surgical Masks on Cardiopulmonary Function in Healthy Young Subjects: A Crossover Study

Objective: Mask plays an important role in preventing infectious respiratory diseases. The influence of wearing masks in physical exercise on the human body needs to be studied. The purpose of this study is to explore the influence of wearing surgical masks on the cardiopulmonary function of healthy people during exercise. Methods: The physiological responses of 71 healthy subjects (35 men and 36 women, age 27.77 ± 7.76 years) to exercises with and without surgical masks (mask-on and mask-off) were analyzed. Cardiopulmonary function and metabolic reaction were measured by the cardiopulmonary exercise test (CPET). All tests were carried out in random sequence and should be completed in 1 week. Results: The CPETs with the mask-on condition were performed undesirably (p < 0.05), and the Borg scale was higher than the mask-off (p < 0.001). Rest oxygen uptake ( V . O 2 ) and carbon dioxide production ( V . CO₂) with the mask-on condition were lower than mask-off (p < 0.01), which were more obvious at peak exercise ( V . O_{2 peak} : 1454.8 ± 418.9 vs. 1628.6 ± 447.2 ml/min, p < 0.001; V . CO_{2 peak} : 1873.0 ± 578.7 vs. 2169.9 ± 627.8 ml/min, p = 0.005), and the anaerobic threshold (AT) brought forward (p < 0.001). At different stages of CPET with the mask-on condition, inspiratory and expiratory time (Te) was longer (p < 0.05), and respiratory frequency (Rf) and minute ventilation ( V . _E ) were shorter than mask-off, especially at peak exercise (Rf _peak : 33.8 ± 7.98 vs. 37.91 ± 6.72 b/min, p < 0.001; V . _Epeak : 55.07 ± 17.28 vs. 66.46 ± 17.93 l/min, p < 0.001). V _T was significantly lower than mask-off just at peak exercise (1.66 ± 0.45 vs. 1.79 ± 0.5 l, p < 0.001). End-tidal oxygen partial pressure (PetO₂), end-tidal carbon dioxide partial pressure (PetCO₂), oxygen ventilation equivalent ( V . _E / V . O₂), and carbon dioxide ventilation equivalent ( V . _E / V . CO₂) with mask-on, which reflected pulmonary ventilation efficiency, were significantly different from mask-off at different stages of CPET (p < 0.05), but no significant difference in percutaneous oxygen saturation (SpO₂) was found. Differences in oxygen pulse ( V . O₂/HR), oxygen uptake efficiency slope (OUES), work efficiency (△ V . O₂/△W), peak heart rate (HR), and peak systolic blood pressure (BP) existed between two conditions (p < 0.05). Conclusion: Wearing surgical masks during aerobic exercise showed certain negative impacts on cardiopulmonary function, especially during high-intensity exercise in healthy young subjects. These results provide an important recommendation for wearing a mask at a pandemic during exercises of varying intensity. Future research should focus on the response of wearing masks in patients with related cardiopulmonary diseases.

The Effect of Surgical Mask Use in Anaerobic Running Performance

COVID-19 restrictions stipulate the mandatory use of surgical masks during outdoor and indoor physical activities. The impact of this on athletic performance and especially on anaerobic physical activities is poorly known. The aim of the present research was to analyze the effect of surgical mask use on the anaerobic running performance of athletes. Modifications in running time, blood lactate, blood glucose, blood oxygen saturation, subjective perceived stress, rating of perceived exertion, and heart rate variability were measured in 50 m and 400 m maximal running tests with and without the use of surgical masks in 72 athletes. The use of a surgical mask increased blood lactate concentration, sympathetic autonomic modulation, perceived exertion, perceived stress, and decreased blood oxygen saturation in 50 and 400 m running tests. Thus, the higher levels of blood lactate and lower blood oxygen saturation require adaptation of the athlete’s rest and recovery periods to the acute workload. The higher level of sympathetic activation makes the acute and chronic control of autonomic modulation essential for an efficient training periodization. Finally, the use of acid buffers such as bicarbonate or sodium citrate would be a recommended ergogenic strategy.

Implications of surgical mask use in physical education lessons

COVID-19 is being a huge challenge for education systems. Mandatory use of face masks in presential classes may lead to psychophysiological impairment of students, which affect lessons. Thus, the aim of the present research was to analyze the effect of mask use in basal psychophysiological status of physical education students prior to a physical education lesson. We analyzed 72 physical education students in two moments prior to two physical education lessons with 48 h between them. Blood oxygen saturation, body, temple and face temperatures, perceived stress and exertion, and heart rate variability were measured. Results showed that the use of surgical masks in physical education students produced a significant increase on subjective stress perception, sympathetic modulation, cardiovascular response, face, and temple temperature while decreasing blood oxygen saturation. We concluded that the use of surgical masks by physical education students induce modifications on the organic status, which could represent a handicap compromising the academic objectives of physical education lessons. This information can help teachers design efficient physical education lessons.

The impact of face masks on children-A mini review

Aim

Face masks are essential during the COVID‐19 pandemic, and the United Nations Children's Fund and the World Health Organization, recommend that they are used for children aged six years and older. However, parents are increasingly expressing concerns about whether these might be physically harmful. This mini review assessed the evidence.

Method

We conducted a narrative review on the effects of mask wearing on physiological variables in children, using PubMed, the Cochrane Library and the World Health Organization COVID‐19 Database up to 7 November 2020. The lack of paediatric studies prompted a second search for adult studies.

Results

We only found two paediatric studies, published in 2019 and 2020. The 2020 study was not related to COVID‐19. Only one study, performed with N95 respirators, collected medical parameters, and this did not suggest any harmful effects of gas exchange. The eight adult studies, including four prompted by the pandemic and one on surgeons, reported that face masks commonly used during the pandemic did not impair gas exchange during rest or mild exercise.

Conclusion

International guidelines recommend face masks for children aged six years and older, but further studies are needed to provide evidence‐based recommendations for different age groups.

The impact of face masks on performance and physiological outcomes during exercise: a systematic review and meta-analysis

Face masks are promoted for preventing spread of viruses; however, wearing a mask during exercise might increase CO₂ rebreathing, decrease arterial oxygenation, and decrease exercise performance. A systematic review and meta-analysis was conducted on the impact of wearing a mask during exercise. Data sources included SPORTDiscus, PubMed, and Medline. Eligibility criteria included all study designs comparing surgical, N95, or cloth masks to a no mask condition during any type of exercise where exercise performance and/or physiological parameters were evaluated. Healthy and clinical participants were included. Mean differences (MD) or standardized mean differences (SMD) with 95% confidence intervals were calculated and pooled effects assessed. Twenty-two studies involving 1573 participants (620 females, 953 males) were included. Surgical, or N95 masks did not impact exercise performance (SMD -0.05 [-0.16, 0.07] and -0.16 [-0.54, 0.22], respectively) but increased ratings of perceived exertion (SMD 0.33 [0.09, 0.58] and 0.61 [0.23, 0.99]) and dyspnea (SMD 0.6 [0.3, 0.9] for all masks). End-tidal CO₂ (MD 3.3 [1.0, 5.6] and 3.7 [3.0, 4.4] mm Hg), and heart rate (MD 2 [0,4] beats/min with N95 masks) slightly increased. Face masks can be worn during exercise with no influences on performance and minimal impacts on physiological variables. PROSPERO registration: CRD42020224988. Novelty: Face masks can be worn during exercise with no impacts on performance and minimal impacts on physiological variables.

Is a Mask That Covers the Mouth and Nose Free from Undesirable Side Effects in Everyday Use and Free of Potential Hazards?

Many countries introduced the requirement to wear masks in public spaces for containing SARS-CoV-2 making it commonplace in 2020. Up until now, there has been no comprehensive investigation as to the adverse health effects masks can cause. The aim was to find, test, evaluate and compile scientifically proven related side effects of wearing masks. For a quantitative evaluation, 44 mostly experimental studies were referenced, and for a substantive evaluation, 65 publications were found. The literature revealed relevant adverse effects of masks in numerous disciplines. In this paper, we refer to the psychological and physical deterioration as well as multiple symptoms described because of their consistent, recurrent and uniform presentation from different disciplines as a Mask-Induced Exhaustion Syndrome (MIES). We objectified evaluation evidenced changes in respiratory physiology of mask wearers with significant correlation of O2 drop and fatigue (p < 0.05), a clustered co-occurrence of respiratory impairment and O2 drop (67%), N95 mask and CO2 rise (82%), N95 mask and O2 drop (72%), N95 mask and headache (60%), respiratory impairment and temperature rise (88%), but also temperature rise and moisture (100%) under the masks. Extended mask-wearing by the general population could lead to relevant effects and consequences in many medical fields.

Health effects of wildfire smoke in children and public health tools: a narrative review

Wildfire smoke is an increasing environmental health threat to which children are particularly vulnerable, for both physiologic and behavioral reasons. To address the need for improved public health messaging this review summarizes current knowledge and knowledge gaps in the health effects of wildfire smoke in children, as well as tools for public health response aimed at children, including consideration of low-cost sensor data, respirators, and exposures in school environments. There is an established literature of health effects in children from components of ambient air pollution, which are also present in wildfire smoke, and an emerging literature on the effects of wildfire smoke, particularly for respiratory outcomes. Low-cost particulate sensors demonstrate the spatial variability of pollution, including wildfire smoke, where children live and play. Surgical masks and respirators can provide limited protection for children during wildfire events, with expected decreases of roughly 20%  and 80% for surgical masks and N95 respirators, respectively. Schools should improve filtration to reduce exposure of our nation's children to smoke during wildfire events. The evidence base described may help clinical and public health authorities provide accurate information to families to improve their decision making.

COVID-19 and the Use of Masks by Children. Statement From the Association of Schools of Public Health in the European Region and the European Academy of Paediatrics

Despite the fact that the use of masks and respirators in adults has already reached a consensus in almost all countries and for situations in which they are recommended, this is not the case for the use of mask by children. This statement, regarding the usage of mask by children, has been jointly produced by the Association of Schools of Public Health in the European Region (ASPHER) and the European Academy of Paediatrics (EAP). It provides recommendations on the size of the mask, the material and ergonomics of children's masks. The authors also discuss the psychological dimension of children when they are asked to wear a mask. Moreover, they tackle the difficulties of children with disabilities.

Impact of respiratory protective devices on respiration: Implications for panic vulnerability during the COVID-19 pandemic

BACKGROUND

The wearing of respiratory protective devices (RPDs) correctly and continually in situations where people are at risk of respiratory infections is crucial for infection prevention. Certain people are poorly compliant with RPDs due to RPD-related annoyance, including respiratory discomfort. We hypothesized that individuals vulnerable to panic attacks are included in this group. No published studies on this topic are available. The evidence for our hypothesis was reviewed in this study as a starting point for future research.

METHODS

We selected a set of experimental studies that measured the respiratory physiological burden in RPD wearers through objective and validated methods. We conducted a bibliographic search of publications in the PubMed database (January 2000-May 2020) to identify representative studies that may be of interest for panic respiratory pathophysiology.

RESULTS

Five studies were included. Wearing RPDs exerted significant respiratory effects, including increased breathing resistance, CO₂ rebreathing due to CO₂ accumulation in the RPD cavity, and decreased inhaled O₂ concentration. We discussed the implications of these effects on the respiratory pathophysiology of panic.

LIMITATIONS

Most studies had a small sample size, with a preponderance of young participants. Different methodologies were used across the studies. Furthermore, differences in physical responses between wearing RPDs in experimental settings or daily life cannot be excluded.

CONCLUSIONS

This research supports the idea that panic-prone individuals may be at higher risk of respiratory discomfort when wearing RPDs, thereby reducing their tolerance for these devices. Strategies to decrease discomfort should be identified to overcome the risk of poor compliance.

Individual- and Household-Level Interventions to Reduce Air Pollution Exposures and Health Risks: a Review of the Recent Literature

PURPOSE OF REVIEW

We reviewed recent peer-reviewed literature on three categories of individual- and household-level interventions against air pollution: air purifiers, facemasks, and behavior change.

RECENT FINDINGS

High-efficiency particulate air/arresting (HEPA) filter air purifier use over days to weeks can substantially reduce fine particulate matter (PM2.5) concentrations indoors and improve subclinical cardiopulmonary health. Modeling studies suggest that the population-level benefits of HEPA filter air purification would often exceed costs. Well-fitting N95 and equivalent respirators can reduce PM2.5 exposure, with several randomized crossover studies also reporting improvements in subclinical cardiovascular health. The health benefits of other types of face coverings have not been tested and their effectiveness in reducing exposure is highly variable, depends largely on fit, and is unrelated to cost. Behavior modifications may reduce exposure, but there has been little research on health impacts. There is now substantial evidence that HEPA filter air purifiers reduce indoor PM2.5 concentrations and improve subclinical health indicators. As a result, their use is being recommended by a growing number of government and public health organizations. Several studies have also reported subclinical cardiovascular health benefits from well-fitting respirators, while evidence of health benefits from other types of facemasks and behavior changes remains very limited. In situations when emissions cannot be controlled at the source, such as during forest fires, individual- or household-level interventions may be the primary option. In most cases, however, such interventions should be supplemental to emission reduction efforts that benefit entire communities.

Assessment of the Wearability of Facemasks against Air Pollution in Primary School-Aged Children in London

Air pollution is a major health problem and children are particularly vulnerable to the adverse effects. Facemasks are one form of protection but, to be effective, they need to filter out airborne pollutants, fit the face well and be wearable. In this pilot study, we assess the perceived wearability of three facemasks (Vogmask, TuHao and ReSpimask) marketed in the UK as being designed to protect children against exposure to air pollution. Twenty-four primary school children wore each facemask during a standardised walking and running activity. After each activity, the children were asked to rate facemask wearability in terms of parameters, such as perceived comfort, hotness, breathability and fit. At the end of the trial, the children compared and identified their preferred facemask. The main complaint about the facemasks was the children's faces being too hot. The ReSpimask was most frequently reported as being perceived to be the hardest to breathe through. The TuHao facemask was the only adjustable strap mask assessed but was reported to be difficult to adjust. Facemasks with a nose clip were frequently rated highest for fit (TuHao and Vogmask). The patterned, cloth fabric Vogmask had significantly higher ratings for appearance and perceived fit. The results show children's perceptions of facemasks are highly affected by the facemask's design, hotness and perceived breathability. By making children's facemasks more appealing, breathable, cooler and improving their fit, wearability may be improved.