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2.
Polym Degrad Stab ; 176: 109162, 2020 Jun.
Article in English | MEDLINE | ID: covidwho-1720750

ABSTRACT

The current COVID-19 pandemic is stretching both the global supply for face masks and personal protective equipment (PPE). Production capacity is severely limited in many countries. This is a call for the R&D community, particularly to those in the polymer degradation and stability field. We have not only an opportunity but an obligation to engage and collaborate with virology and bio-medical experts. We require comparative R&D for extended, reuse and recyclability options. There is urgent need for large scale institutional approaches and methods that can be quickly applied locally by non-experts with limited resources.

3.
Disaster Med Public Health Prep ; : 1-16, 2021 Apr 30.
Article in English | MEDLINE | ID: covidwho-1700344

ABSTRACT

Objective: Bottlenecks in the personal protective equipment (PPE) supply chain have contributed to shortages of PPE during the COVID-19 pandemic, resulting in fractures in the functionality of healthcare systems. This study was conducted with the aim of determining the effectiveness of retrofitted commercial snorkel masks as an alternative respirator for healthcare workers during infectious disease outbreaks.Methods: A retrospective analysis was performed, analyzing qualitative and quantitative fit test results of the retrofitted Aria Ocean Reef® full-face snorkeling mask on healthcare workers at the McGill University Health Centre between April-June 2020. Historical fit test results, using medical-grade respirators, for healthcare workers were also analyzed.Results: During the study period, 71 participants volunteered for fit testing, 60.6% of which were nurses. The overall fit test passing rate using the snorkel mask was 83.1%. Of the participants who did not previously pass fit testing with medical-grade respirators, 80% achieved a passing fit test with the snorkel respirator.Conclusions: The results suggest that this novel respirator may be an effective and feasible alternative solution to address PPE shortages, while still providing healthcare workers with ample protection. Additional robust testing will be required to ensure that respirator fit is maintained, after numerous rounds of disinfection.

4.
Br J Sports Med ; 56(2): 107-113, 2022 Jan.
Article in English | MEDLINE | ID: covidwho-1604636

ABSTRACT

OBJECTIVES: To (1) determine if wearing a cloth face mask significantly affected exercise performance and associated physiological responses, and (2) describe perceptual measures of effort and participants' experiences while wearing a face mask during a maximal treadmill test. METHODS: Randomised controlled trial of healthy adults aged 18-29 years. Participants completed two (with and without a cloth face mask) maximal cardiopulmonary exercise tests (CPETs) on a treadmill following the Bruce protocol. Blood pressure, heart rate, oxygen saturation, exertion and shortness of breath were measured. Descriptive data and physical activity history were collected pretrial; perceptions of wearing face masks and experiential data were gathered immediately following the masked trial. RESULTS: The final sample included 31 adults (age=23.2±3.1 years; 14 women/17 men). Data indicated that wearing a cloth face mask led to a significant reduction in exercise time (-01:39±01:19 min/sec, p<0.001), maximal oxygen consumption (VO2max) (-818±552 mL/min, p<0.001), minute ventilation (-45.2±20.3 L/min), maximal heart rate (-8.4±17.0 beats per minute, p<0.01) and increased dyspnoea (1.7±2.9, p<0.001). Our data also suggest that differences in SpO2 and rating of perceived exertion existed between the different stages of the CPET as participant's exercise intensity increased. No significant differences were found between conditions after the 7-minute recovery period. CONCLUSION: Cloth face masks led to a 14% reduction in exercise time and 29% decrease in VO2max, attributed to perceived discomfort associated with mask-wearing. Compared with no mask, participants reported feeling increasingly short of breath and claustrophobic at higher exercise intensities while wearing a cloth face mask. Coaches, trainers and athletes should consider modifying the frequency, intensity, time and type of exercise when wearing a cloth face mask.


Subject(s)
COVID-19 , Running , Adolescent , Adult , Exercise Test , Female , Heart Rate , Humans , Male , Masks , Young Adult
5.
Public Health Pract (Oxf) ; 2: 100094, 2021 Nov.
Article in English | MEDLINE | ID: covidwho-1595256

ABSTRACT

OBJECTIVES: This study examines the response of a group of volunteers in Ribeirão Preto, Brazil, as the city faced an unprecedented demand for face masks during the onset of the COVID-19 crisis in 2020. The performance of artisanal-produced masks was compared with industry equivalents. STUDY DESIGN: Case report with comparative testing. METHODS: A comparison was made between two parallel projects that produced single-use masks for healthcare workers and reusable masks for the community. Mask samples were tested for filtration efficiency (FE) and breathability (pressure drop). RESULTS: Results for FE averaged 40-60% for healthcare masks and 10% for community masks; both types of masks were tested for particle sizes of 0.3 â€‹µm. CONCLUSIONS: While performance was inferior to standard comparators, the masks investigated in this study afforded a level of protection in the absence of alternatives, especially in non-aerosol generating contexts. The findings of this study are useful for communities with limited resources in other developing countries. In addition, insights can be gained from the experiences in Ribeirão Preto in terms of how to respond to future health emergencies.

6.
Appl Physiol Nutr Metab ; 46(7): 753-762, 2021 Jul.
Article in English | MEDLINE | ID: covidwho-1571437

ABSTRACT

We sought to determine the impact of wearing cloth or surgical masks on the cardiopulmonary responses to moderate-intensity exercise. Twelve subjects (n = 5 females) completed three, 8-min cycling trials while breathing through a non-rebreathing valve (laboratory control), cloth, or surgical mask. Heart rate (HR), oxyhemoglobin saturation (SpO2), breathing frequency, mouth pressure, partial pressure of end-tidal carbon dioxide (PetCO2) and oxygen (PetO2), dyspnea were measured throughout exercise. A subset of n = 6 subjects completed an additional exercise bout without a mask (ecological control). There were no differences in breathing frequency, HR or SpO2 across conditions (all p > 0.05). Compared with the laboratory control (4.7 ± 0.9 cmH2O [mean ± SD]), mouth pressure swings were smaller with the surgical mask (0.9 ± 0.7; p < 0.0001), but similar with the cloth mask (3.6 ± 4.8 cmH2O; p = 0.66). Wearing a cloth mask decreased PetO2 (-3.5 ± 3.7 mm Hg) and increased PetCO2 (+2.0 ± 1.3 mm Hg) relative to the ecological control (both p < 0.05). There were no differences in end-tidal gases between mask conditions and laboratory control (both p > 0.05). Dyspnea was similar between the control conditions and the surgical mask (p > 0.05) but was greater with the cloth mask compared with laboratory (+0.9 ± 1.2) and ecological (+1.5 ± 1.3) control conditions (both p < 0.05). Wearing a mask during short-term moderate-intensity exercise may increase dyspnea but has minimal impact on the cardiopulmonary response. Novelty: Wearing surgical or cloth masks during exercise has no impact on breathing frequency, tidal volume, oxygenation, and heart rate However, there are some changes in inspired and expired gas fractions that are physiologically irrelevant. In young healthy individuals, wearing surgical or cloth masks during submaximal exercise has few physiological consequences.


Subject(s)
Exercise/physiology , Heart Rate , Masks , Oxyhemoglobins/metabolism , Respiratory Rate , Adult , COVID-19/prevention & control , Carbon Dioxide/physiology , Dyspnea/physiopathology , Equipment Design , Exercise Test , Face , Female , Humans , Male , Mouth/physiology , Oxygen/physiology , Partial Pressure , Pressure , Skin Temperature , Tidal Volume , Young Adult
7.
Med Pr ; 72(3): 327-334, 2021 Jun 30.
Article in Polish | MEDLINE | ID: covidwho-1413301

ABSTRACT

Generally, COVID-19 is an acute contagious disease caused by the SARS­CoV-2 virus. The main route of human-to-human transmission is through contact with infectious secretions from the respiratory tract. Clinical manifestations vary from mild non-specific symptoms to life-threatening conditions. Since WHO declared COVID-19 a pandemic in March 2020, it has affected many medical, legal, social and economic aspects of everyday life in countries around the world. In this article, the authors present a summary of recommendations for taking care of otorhinolaryngology patients in outpatient settings and the legal basis referring to a risk of infection in doctor's office. In the selection of articles, the authors used English- and Polish-language online medical databases, typing the following keywords: SARS­CoV-2, COVID-19, otolaryngology, endoscopy, personal protective equipment, and legal responsibility of the physician. The mucosa of the upper respiratory tract is a potential site of virus replication. The specificity of an ear, nose and throat (ENT) examination and a direct patient-doctor contact favor the transmission of the infection. The authors discussed the elements of self-protection of medical personnel and the legal aspects a risk of the patient contracting the infection in the otolaryngology office. In the case of a direct contact with the patient, the following medical personal protective equipment is required: a cap, a mask with an FFP-2 filter, goggles, an apron and gloves. If, during the visit, exposure to secretions or aerosol from the respiratory tract is expected, the personnel should additionally wear a visor and a waterproof apron. The patient's visit in the clinic should be preceded by telemedicine consultation. Patients should be screened prior to having a direct contact with a physician, using a short patient questionnaire. The questionnaire may consist of simple questions about the characteristic symptoms of the SARS­CoV-2 infection and exposure to a sick person in the past 14 days. The question of staying in the areas of a high infection risk appears of little importance in view of the whole of Poland being perceived as constituting such an area. Due to the spread of the SARS­CoV-2 virus, new procedures for providing medical services have been introduced. In the case of claims on the part of the patient, the only protection the medical personnel or facility can provide is confirmation of scrupulous compliance with medical procedures . Med Pr. 2021;72(3):327-34.


Subject(s)
COVID-19/prevention & control , Infection Control/standards , Otolaryngology/standards , COVID-19/transmission , Health Personnel , Humans , Infection Control/legislation & jurisprudence , Otolaryngology/legislation & jurisprudence , Personal Protective Equipment
8.
MMWR Morb Mortal Wkly Rep ; 70(21): 779-784, 2021 May 28.
Article in English | MEDLINE | ID: covidwho-1395448

ABSTRACT

To meet the educational, physical, social, and emotional needs of children, many U.S. schools opened for in-person learning during fall 2020 by implementing strategies to prevent transmission of SARS-CoV-2, the virus that causes COVID-19 (1,2). To date, there have been no U.S. studies comparing COVID-19 incidence in schools that varied in implementing recommended prevention strategies, including mask requirements and ventilation improvements* (2). Using data from Georgia kindergarten through grade 5 (K-5) schools that opened for in-person learning during fall 2020, CDC and the Georgia Department of Public Health (GDPH) assessed the impact of school-level prevention strategies on incidence of COVID-19 among students and staff members before the availability of COVID-19 vaccines.† Among 169 K-5 schools that participated in a survey on prevention strategies and reported COVID-19 cases during November 16-December 11, 2020, COVID-19 incidence was 3.08 cases among students and staff members per 500 enrolled students.§ Adjusting for county-level incidence, COVID-19 incidence was 37% lower in schools that required teachers and staff members to use masks, and 39% lower in schools that improved ventilation, compared with schools that did not use these prevention strategies. Ventilation strategies associated with lower school incidence included methods to dilute airborne particles alone by opening windows, opening doors, or using fans (35% lower incidence), or in combination with methods to filter airborne particles with high-efficiency particulate absorbing (HEPA) filtration with or without purification with ultraviolet germicidal irradiation (UVGI) (48% lower incidence). Multiple strategies should be implemented to prevent transmission of SARS-CoV-2 in schools (2); mask requirements for teachers and staff members and improved ventilation are important strategies that elementary schools could implement as part of a multicomponent approach to provide safer, in-person learning environments. Universal and correct mask use is still recommended by CDC for adults and children in schools regardless of vaccination status (2).


Subject(s)
COVID-19/prevention & control , Masks/statistics & numerical data , Schools , Ventilation/standards , COVID-19/epidemiology , Child , Georgia/epidemiology , Humans , Incidence
9.
MMWR Morb Mortal Wkly Rep ; 70(7): 254-257, 2021 Feb 19.
Article in English | MEDLINE | ID: covidwho-1389863

ABSTRACT

Universal masking is one of the prevention strategies recommended by CDC to slow the spread of SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19) (1). As of February 1, 2021, 38 states and the District of Columbia had universal masking mandates. Mask wearing has also been mandated by executive order for federal property* as well as on domestic and international transportation conveyances.† Masks substantially reduce exhaled respiratory droplets and aerosols from infected wearers and reduce exposure of uninfected wearers to these particles. Cloth masks§ and medical procedure masks¶ fit more loosely than do respirators (e.g., N95 facepieces). The effectiveness of cloth and medical procedure masks can be improved by ensuring that they are well fitted to the contours of the face to prevent leakage of air around the masks' edges. During January 2021, CDC conducted experimental simulations using pliable elastomeric source and receiver headforms to assess the extent to which two modifications to medical procedure masks, 1) wearing a cloth mask over a medical procedure mask (double masking) and 2) knotting the ear loops of a medical procedure mask where they attach to the mask's edges and then tucking in and flattening the extra material close to the face (knotted and tucked masks), could improve the fit of these masks and reduce the receiver's exposure to an aerosol of simulated respiratory droplet particles of the size considered most important for transmitting SARS-CoV-2. The receiver's exposure was maximally reduced (>95%) when the source and receiver were fitted with modified medical procedure masks. These laboratory-based experiments highlight the importance of good fit to optimize mask performance. Until vaccine-induced population immunity is achieved, universal masking is a highly effective means to slow the spread of SARS-CoV-2** when combined with other protective measures, such as physical distancing, avoiding crowds and poorly ventilated indoor spaces, and good hand hygiene. Innovative efforts to improve the fit of cloth and medical procedure masks to enhance their performance merit attention.


Subject(s)
COVID-19/prevention & control , Masks/standards , COVID-19/epidemiology , COVID-19/transmission , Centers for Disease Control and Prevention, U.S. , Humans , Masks/statistics & numerical data , United States/epidemiology
10.
PLoS One ; 16(6): e0250854, 2021.
Article in English | MEDLINE | ID: covidwho-1388910

ABSTRACT

The use of personal protective equipment (PPE) has been considered the most effective way to avoid the contamination of healthcare workers by different microorganisms, including SARS-CoV-2. A spray disinfection technology (chamber) was developed, and its efficacy in instant decontamination of previously contaminated surfaces was evaluated in two exposure times. Seven test microorganisms were prepared and inoculated on the surface of seven types of PPE (respirator mask, face shield, shoe, glove, cap, safety glasses and lab coat). The tests were performed on previously contaminated PPE using a manikin with a motion device for exposure to the chamber with biocidal agent (sodium hypochlorite) for 10 and 30s. In 96.93% of the experimental conditions analyzed, the percentage reduction was >99% (the number of viable cells found on the surface ranged from 4.3x106 to <10 CFU/mL). The samples of E. faecalis collected from the glove showed the lowest percentages reduction, with 86.000 and 86.500% for exposure times of 10 and 30 s, respectively. The log10 reduction values varied between 0.85 log10 (E. faecalis at 30 s in glove surface) and 9.69 log10 (E. coli at 10 and 30 s in lab coat surface). In general, E. coli, S. aureus, C. freundii, P. mirabilis, C. albicans and C. parapsilosis showed susceptibility to the biocidal agent under the tested conditions, with >99% reduction after 10 and 30s, while E. faecalis and P. aeruginosa showed a lower susceptibility. The 30s exposure time was more effective for the inactivation of the tested microorganisms. The results show that the spray disinfection technology has the potential for instant decontamination of PPE, which can contribute to an additional barrier for infection control of healthcare workers in the hospital environment.


Subject(s)
COVID-19/prevention & control , Decontamination , Infection Control , Infectious Disease Transmission, Patient-to-Professional/prevention & control , Protective Clothing , Respiratory Protective Devices , SARS-CoV-2 , Bacteria , Bacterial Infections/epidemiology , Bacterial Infections/prevention & control , Bacterial Infections/transmission , COVID-19/epidemiology , COVID-19/transmission , Decontamination/instrumentation , Decontamination/methods , Humans
11.
PLoS One ; 16(2): e0247414, 2021.
Article in English | MEDLINE | ID: covidwho-1388900

ABSTRACT

BACKGROUND: Facemasks are recommended to reduce the spread of SARS-CoV-2, but concern about inadequate gas exchange is an often cited reason for non-compliance. RESEARCH QUESTION: Among adult volunteers, do either cloth masks or surgical masks impair oxygenation or ventilation either at rest or during physical activity? STUDY DESIGN AND METHODS: With IRB approval and informed consent, we measured heart rate (HR), transcutaneous carbon dioxide (CO2) tension and oxygen levels (SpO2) at the conclusion of six 10-minute phases: sitting quietly and walking briskly without a mask, sitting quietly and walking briskly while wearing a cloth mask, and sitting quietly and walking briskly while wearing a surgical mask. Brisk walking required at least a 10bpm increase in heart rate. Occurrences of hypoxemia (decrease in SpO2 of ≥3% from baseline to a value of ≤94%) and hypercarbia (increase in CO2 tension of ≥5 mmHg from baseline to a value of ≥46 mmHg) in individual subjects were collected. Wilcoxon signed-rank was used for pairwise comparisons among values for the whole cohort (e.g. walking without a mask versus walking with a cloth mask). RESULTS: Among 50 adult volunteers (median age 33 years; 32% with a co-morbidity), there were no episodes of hypoxemia or hypercarbia (0%; 95% confidence interval 0-1.9%). In paired comparisons, there were no statistically significant differences in either CO2 or SpO2 between baseline measurements without a mask and those while wearing either kind of mask mask, both at rest and after walking briskly for ten minutes. INTERPRETATION: The risk of pathologic gas exchange impairment with cloth masks and surgical masks is near-zero in the general adult population.


Subject(s)
COVID-19/prevention & control , Masks , Oxygen/metabolism , Pulmonary Ventilation/physiology , Adult , COVID-19/psychology , COVID-19/transmission , Carbon Dioxide/metabolism , Exercise/physiology , Female , Heart Rate/physiology , Humans , Hypoxia/etiology , Hypoxia/metabolism , Male , Masks/adverse effects , N95 Respirators/adverse effects , Rest/physiology , SARS-CoV-2/isolation & purification , Walking/physiology
12.
ACS Nano ; 14(7): 9188-9200, 2020 07 28.
Article in English | MEDLINE | ID: covidwho-1387153

ABSTRACT

Filtration efficiency (FE), differential pressure (ΔP), quality factor (QF), and construction parameters were measured for 32 cloth materials (14 cotton, 1 wool, 9 synthetic, 4 synthetic blends, and 4 synthetic/cotton blends) used in cloth masks intended for protection from the SARS-CoV-2 virus (diameter 100 ± 10 nm). Seven polypropylene-based fiber filter materials were also measured including surgical masks and N95 respirators. Additional measurements were performed on both multilayered and mixed-material samples of natural, synthetic, or natural-synthetic blends to mimic cloth mask construction methods. Materials were microimaged and tested against size selected NaCl aerosol with particle mobility diameters between 50 and 825 nm. Three of the top five best performing samples were woven 100% cotton with high to moderate yarn counts, and the other two were woven synthetics of moderate yarn counts. In contrast to recently published studies, samples utilizing mixed materials did not exhibit a significant difference in the measured FE when compared to the product of the individual FE for the components. The FE and ΔP increased monotonically with the number of cloth layers for a lightweight flannel, suggesting that multilayered cloth masks may offer increased protection from nanometer-sized aerosol with a maximum FE dictated by breathability (i.e., ΔP).


Subject(s)
Coronavirus Infections/prevention & control , Masks/standards , Pandemics/prevention & control , Personal Protective Equipment/standards , Pneumonia, Viral/prevention & control , Respiratory Protective Devices/standards , Textiles/standards , Aerosols/chemistry , Betacoronavirus/pathogenicity , COVID-19 , Filtration , Humans , Masks/virology , Nanoparticles/chemistry , Nanoparticles/virology , Personal Protective Equipment/virology , Respiratory Protective Devices/virology , SARS-CoV-2 , Textiles/adverse effects , Textiles/virology
13.
PeerJ ; 9: e11397, 2021.
Article in English | MEDLINE | ID: covidwho-1359402

ABSTRACT

BACKGROUND: Air pollution leads to many adverse health conditions, mainly manifested by respiratory or cardiac symptoms. Previous studies are limited as to whether air pollutants were associated to influenza-like illness (ILI). This study aimed to explore the association between air pollutants and outpatient visits for ILI, especially during an outbreak of influenza. METHODS: Daily counts of hospital visits for ILI were obtained from Peking University Third Hospital between January 1, 2015, and March 31, 2018. A generalized additive Poisson model was applied to examine the associations between air pollutants concentrations and daily outpatient visits for ILI when adjusted for the meteorological parameters. RESULTS: There were 35862 outpatient visits at the fever clinic for ILI cases. Air quality index (AQI), PM2.5, PM10, CO and O3 on lag0 days, as well as nitrogen dioxide (NO2) and sulfur dioxide (SO2) on lag1 days, were significantly associated with an increased risk of outpatient visits for ILI from January 2015 to November 2017. From December 2017 to March 2018, on lag0 days, air pollutants PM2.5 [risk ratio (RR) = 0.971, 95% CI: 0.963-0.979], SO2 (RR = 0.892, 95% CI: 0.840-0.948) and CO (RR = 0.306, 95% CI: 0.153-0.612) were significantly associated with a decreased risk of outpatient visits for ILI. Interestingly, on the lag2 days, all the pollutants were significantly associated with a reduced risk of outpatient visits for ILI except for O3. We did not observe the linear correlations between the outpatient visits for ILI and any of air pollutants, which were instead associated via a curvilinear relationship. CONCLUSIONS: We found that the air pollutants may be associated with an increased risk of outpatient visits for ILI during the non-outbreak period and with a decreased risk during the outbreak period, which may be linked with the use of disposable face masks and the change of outdoor activities. These findings expand the current knowledge of ILI outpatient visits correlated with air pollutants during an influenza pandemic.

14.
Infect Dis Now ; 51(5): 410-417, 2021 Aug.
Article in English | MEDLINE | ID: covidwho-1349451

ABSTRACT

SARS-CoV-2 mainly infects the respiratory tract, and presents significantly higher active replication in the upper airways. To remain viable and infectious, the SARS-CoV-2 virion must be complete and integral, which is not easily demonstrated in the environment by positive reverse transcriptase PCR results. Real-life conditions in healthcare settings may be conducive to SARS-CoV-2 RNA dissemination in the environment but without evidence of its viability and infectiveness in air. Theoretically, SARS-CoV-2 shedding and dissemination nonetheless appears to be air-mediated, and a distinction between "air" and "droplet" transmission is too schematic to reflect the reality of the respiratory particles emitted by patients, between which a continuum exists. Airborne transmission is influenced by numerous environmental conditions that are not transposable between different viral agents and situations in healthcare settings or in the community. Even though international guidelines on "droplet" versus "air" precautions and personal protective equipment (surgical versus respirator masks) are under discussion, the existing literature underscores the effectiveness of "droplet" precautions as a means of protecting healthcare workers. Differentiation in guidelines between healthcare venues, community settings and, more generally, confined environments is of paramount importance, especially insofar as it underlines the abiding pandemic-related need for systematic mask wearing by the general population.


Subject(s)
Air Microbiology , COVID-19/transmission , Health Personnel , Infectious Disease Transmission, Patient-to-Professional/prevention & control , Occupational Diseases/prevention & control , Occupational Diseases/virology , SARS-CoV-2 , Humans
15.
Dermatol Ther ; 34(3): e14837, 2021 05.
Article in English | MEDLINE | ID: covidwho-1257898

ABSTRACT

It has become a general practice worldwide to wear a face mask serving as a barrier against the transmission of pathogens. This has prompted us to investigate whether masks could also protect our skin from UV radiation. We have studied eight masks, four surgical and four "homemade" using an in vitro method. The study demonstrated that they all offered protection against both UVB and UVA radiation. As with clothing, fabric masks offer the highest level of protection against UV radiation.


Subject(s)
COVID-19 , Humans , Masks , Skin , Ultraviolet Rays/adverse effects
16.
JMIR Public Health Surveill ; 7(5): e26372, 2021 05 26.
Article in English | MEDLINE | ID: covidwho-1290683

ABSTRACT

BACKGROUND: The COVID-19 epidemic and the related containment strategies may affect parental and pediatric health behaviors. OBJECTIVE: The goal of this study was to assess the change in children's and adolescents' prevention and vaccination behaviors amid China's COVID-19 epidemic. METHODS: We conducted a cross-sectional online survey in mid-March 2020 using proportional quota sampling in Wuhan (the epidemic epicenter) and Shanghai (a nonepicenter). Data were collected from 1655 parents with children aged 3 to 17 years. Children's and adolescents' prevention behaviors and regular vaccination behaviors before and during the epidemic were assessed. Descriptive analyses were used to investigate respondents' characteristics, public health prevention behaviors, unproven protection behaviors, and vaccination behaviors before and during the COVID-19 epidemic. Univariate analyses were performed to compare differences in outcome measures between cities and family characteristics, using chi-square tests or Fisher exact tests (if expected frequency was <5) and analyses of variance. Multivariate logistic regressions were used to identify the factors and disparities associated with prevention and vaccination behaviors. RESULTS: Parent-reported prevention behaviors increased among children and adolescents during the COVID-19 epidemic compared with those before the epidemic. During the epidemic, 82.2% (638/776) of children or adolescents always wore masks when going out compared with 31.5% (521/1655) before the epidemic; in addition, 25.0% (414/1655) and 79.8% (1321/1655) had increased their frequency and duration of handwashing, respectively, although only 46.9% (776/1655) went out during the epidemic. Meanwhile, 56.1% (928/1655) of the families took unproven remedies against COVID-19. Parent-reported vaccination behaviors showed mixed results, with 74.8% (468/626) delaying scheduled vaccinations and 80.9% (1339/1655) planning to have their children get the influenza vaccination after the epidemic. Regarding socioeconomic status, children and adolescents from larger families and whose parents had lower education levels were less likely to improve prevention behaviors but more likely to take unproven remedies. Girls were less likely than boys to always wear a mask when going out and wash their hands. CONCLUSIONS: Prevention behaviors and attitudes toward influenza vaccination have improved during the COVID-19 epidemic. Public health prevention measures should be continuously promoted, particularly among girls, parents with lower education levels, and larger families. Meanwhile, misinformation about COVID-19 remains a serious challenge and needs to be addressed by public health stakeholders.


Subject(s)
Adolescent Behavior , COVID-19/prevention & control , Child Behavior , Hand Disinfection , Masks , Pandemics , Vaccination , Adolescent , Adult , Child , Child, Preschool , China , Cross-Sectional Studies , Epidemics , Female , Health Behavior , Humans , Male , Parents , Patient Acceptance of Health Care , SARS-CoV-2 , Social Class , Surveys and Questionnaires
17.
Ear Hear ; 42(4): 772-781, 2021.
Article in English | MEDLINE | ID: covidwho-1280144

ABSTRACT

OBJECTIVE: The purpose of this study was to assess the speech recognition in noise when using a transparent mask that allows greater visibility of the talker's face compared to an opaque mask in persons with normal and impaired hearing via an online format. DESIGN: A repeated-measures design was used to evaluate the auditory-visual recognition of sentences recorded in background noise with transparent and opaque face masks, and without a mask (N = 154). In a smaller follow-up study (N = 29), the same files were presented via auditory-only presentation to determine if differences observed in the transparent and opaque mask conditions were attributable to additional visual cues or to acoustic differences between the recordings of the two mask types. Listeners completed the 40-minute online session on a computer, laptop, or tablet in a quiet room via their personal listening devices (earbuds or hearing assistive device). The adult volunteers who used English as their first language were recruited through social media links and email and categorized into three groups: normal hearing and confirmed or suspected hearing loss either with or without the use of assistive listening devices. RESULTS: Auditory-visual recognition of sentences recorded with the transparent mask was significantly better (M = 68.9%) than for sentences recorded with the opaque mask (M = 58.9%) for all participants. There was a trend for those who used hearing assistive technology to score lower than the other two groups who had similar performance across all conditions regardless of the mask type. Subjective ratings of confidence and concentration followed the expected pattern based on objective scores. Results of the auditory-only presentation of the sentences to listeners with normal hearing suggested that the transparent mask benefits were not attributable to an acoustic advantage but rather to the addition of the visual cues of the talker's face available through the transparent mask. In fact, performance in the auditory-only presentation was significantly lower with the transparent mask (M = 40.7%) compared to the opaque mask (M = 58.2%). CONCLUSIONS: Use of transparent masks can significantly facilitate speech recognition in noise even for persons with normal hearing and thus may reduce stressful communication challenges experienced in medical, employment, and educational settings during the global pandemic. To mitigate the spread of COVID-19 and facilitate communication, safety-approved transparent masks are strongly encouraged over opaque masks.


Subject(s)
COVID-19 , Communication , Masks , Speech Perception , Adult , Humans , SARS-CoV-2
18.
ACS Biomater Sci Eng ; 7(6): 2791-2802, 2021 06 14.
Article in English | MEDLINE | ID: covidwho-1275857

ABSTRACT

Cloth masks can be an alternative to medical masks during pandemics. Recent studies have examined the performance of fabrics under various conditions; however, the performance against violent respiratory events such as human sneezes is yet to be explored. Accordingly, we present a comprehensive experimental study using sneezes by a healthy adult and a tailored image-based flow measurement diagnostic system evaluating all dimensions of protection of commonly available fabrics and their layered combinations: the respiratory droplet blocking efficiency, water resistance, and breathing resistance. Our results reveal that a well-designed cloth mask can outperform a three-layered surgical mask for such violent respiratory events. Specifically, increasing the number of layers significantly increases the droplet blocking efficiency, on average by ∼20 times per additional fabric layer. A minimum of three layers is necessary to resemble the droplet blocking performance of surgical masks, and a combination of cotton/linen (hydrophilic inner layer)-blends (middle layer)-polyester/nylon (hydrophobic outer layer) exhibited the best performance among overall indicators tested. In an optimum three-layered design, the average thread count should be greater than 200, and the porosity should be less than 2%. Furthermore, machine washing at 60 °C did not significantly impact the performance of cloth masks. These findings inform the design of high-performing homemade cloth masks.


Subject(s)
COVID-19 , Adult , Humans , Masks , Pandemics , SARS-CoV-2 , Textiles
19.
PLoS One ; 16(6): e0252143, 2021.
Article in English | MEDLINE | ID: covidwho-1270947

ABSTRACT

The use of face masks by the general population during viral outbreaks such as the COVID-19 pandemic, although at times controversial, has been effective in slowing down the spread of the virus. The extent to which face masks mitigate the transmission is highly dependent on how well the mask fits each individual. The fit of simple cloth masks on the face, as well as the resulting perimeter leakage and face mask efficacy, are expected to be highly dependent on the type of mask and facial topology. However, this effect has, to date, not been adequately examined and quantified. Here, we propose a framework to study the efficacy of different mask designs based on a quasi-static mechanical model of the deployment of face masks onto a wide range of faces. To illustrate the capabilities of the proposed framework, we explore a simple rectangular cloth mask on a large virtual population of subjects generated from a 3D morphable face model. The effect of weight, age, gender, and height on the mask fit is studied. The Centers for Disease Control and Prevention (CDC) recommended homemade cloth mask design was used as a basis for comparison and was found not to be the most effective design for all subjects. We highlight the importance of designing masks accounting for the widely varying population of faces. Metrics based on aerodynamic principles were used to determine that thin, feminine, and young faces were shown to benefit from mask sizes smaller than that recommended by the CDC. Besides mask size, side-edge tuck-in, or pleating, of the masks as a design parameter was also studied and found to have the potential to cause a larger localized gap opening.


Subject(s)
COVID-19/prevention & control , Face/anatomy & histology , Masks/standards , SARS-CoV-2/isolation & purification , Textiles/standards , Adolescent , Adult , Algorithms , COVID-19/epidemiology , COVID-19/virology , Child , Cohort Studies , Computer Simulation , Female , Humans , Imaging, Three-Dimensional , Male , Masks/classification , Middle Aged , Models, Theoretical , Pandemics , SARS-CoV-2/physiology , Young Adult
20.
J Occup Environ Hyg ; 18(7): 345-360, 2021 07.
Article in English | MEDLINE | ID: covidwho-1269471

ABSTRACT

First responders may have high SARS-CoV-2 infection risks due to working with potentially infected patients in enclosed spaces. The study objective was to estimate infection risks per transport for first responders and quantify how first responder use of N95 respirators and patient use of cloth masks can reduce these risks. A model was developed for two Scenarios: an ambulance transport with a patient actively emitting a virus in small aerosols that could lead to airborne transmission (Scenario 1) and a subsequent transport with the same respirator or mask use conditions, an uninfected patient; and remaining airborne SARS-CoV-2 and contaminated surfaces due to aerosol deposition from the previous transport (Scenario 2). A compartmental Monte Carlo simulation model was used to estimate the dispersion and deposition of SARS-CoV-2 and subsequent infection risks for first responders, accounting for variability and uncertainty in input parameters (i.e., transport duration, transfer efficiencies, SARS-CoV-2 emission rates from infected patients, etc.). Infection risk distributions and changes in concentration on hands and surfaces over time were estimated across sub-Scenarios of first responder respirator use and patient cloth mask use. For Scenario 1, predicted mean infection risks were reduced by 69%, 48%, and 85% from a baseline risk (no respirators or face masks used) of 2.9 × 10-2 ± 3.4 × 10-2 when simulated first responders wore respirators, the patient wore a cloth mask, and when first responders and the patient wore respirators or a cloth mask, respectively. For Scenario 2, infection risk reductions for these same Scenarios were 69%, 50%, and 85%, respectively (baseline risk of 7.2 × 10-3 ± 1.0 × 10-2). While aerosol transmission routes contributed more to viral dose in Scenario 1, our simulations demonstrate the ability of face masks worn by patients to additionally reduce surface transmission by reducing viral deposition on surfaces. Based on these simulations, we recommend the patient wear a face mask and first responders wear respirators, when possible, and disinfection should prioritize high use equipment.


Subject(s)
COVID-19/transmission , Infectious Disease Transmission, Patient-to-Professional/prevention & control , Masks/virology , N95 Respirators/virology , SARS-CoV-2 , Aerosols , Air Microbiology , Ambulances , COVID-19/prevention & control , Computer Simulation , Emergency Responders , Equipment Contamination , Humans , Monte Carlo Method , Respiratory Protective Devices/virology , Risk Reduction Behavior , Transportation of Patients
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