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MSphere Oct 2020Guidelines from the CDC and the WHO recommend the wearing of face masks to prevent the spread of coronavirus (CoV) disease 2019 (COVID-19); however, the protective...
Guidelines from the CDC and the WHO recommend the wearing of face masks to prevent the spread of coronavirus (CoV) disease 2019 (COVID-19); however, the protective efficiency of such masks against airborne transmission of infectious severe acute respiratory syndrome CoV-2 (SARS-CoV-2) droplets/aerosols is unknown. Here, we developed an airborne transmission simulator of infectious SARS-CoV-2-containing droplets/aerosols produced by human respiration and coughs and assessed the transmissibility of the infectious droplets/aerosols and the ability of various types of face masks to block the transmission. We found that cotton masks, surgical masks, and N95 masks all have a protective effect with respect to the transmission of infective droplets/aerosols of SARS-CoV-2 and that the protective efficiency was higher when masks were worn by a virus spreader. Importantly, medical masks (surgical masks and even N95 masks) were not able to completely block the transmission of virus droplets/aerosols even when completely sealed. Our data will help medical workers understand the proper use and performance of masks and determine whether they need additional equipment to protect themselves from infected patients. Airborne simulation experiments showed that cotton masks, surgical masks, and N95 masks provide some protection from the transmission of infective SARS-CoV-2 droplets/aerosols; however, medical masks (surgical masks and even N95 masks) could not completely block the transmission of virus droplets/aerosols even when sealed.
Topics: Aerosols; Air Microbiology; Betacoronavirus; COVID-19; Coronavirus Infections; Health Personnel; Humans; Masks; Pandemics; Pneumonia, Viral; SARS-CoV-2
PubMed: 33087517
DOI: 10.1128/mSphere.00637-20 -
Annali Di Igiene : Medicina Preventiva... 2021Health authorities and organizations consider non-medical face masks as an additional passive means to prevent virus diffusion. Communication strategies disseminate... (Review)
Review
BACKGROUND
Health authorities and organizations consider non-medical face masks as an additional passive means to prevent virus diffusion. Communication strategies disseminate information among the population that such masks are essential for mitigating virus diffusion. However, scientific studies are not conclusive in showing the undisputed filtration efficiency of fabric/cloth facial masks (both commercial and homemade).
OBJECTIVES
This study examines scientific data about the effectiveness of face masks before and during the COVID-19 emergency. Present trends in the making of commercial and homemade fabric/cloth face masks are also examined.
METHODS
Statistical data of published studies are analyzed and compared. Main considerations and sugge-stions are also extracted and discussed. Current approaches are examined for assessing the characteristics and effectiveness of fabric/cloth commercial and homemade face masks intended for the population.
RESULTS
Conflicting data exist as to whether non-medical masks have a protective effect from the spread of respiratory viruses. Both medical masks (MDs) and respiratory personal protection equipment (PPE) show a given effectiveness value.
CONCLUSION
Concerning commercial and homemade fabric/cloth masks, giving general indications on the choice of materials and their assemblage is difficult as it is not possible to assess the effectiveness of the filter media with respect to the kind of multiphase fluid that may be emitted upon breathing, sneezing, or coughing under different environmental conditions. This is particularly important because airflow rate, temperature, humidity, and duration of use will affect the performance of filter media. Moreover, while a mask may have excellent filter media, droplets may leak into the face-piece unless there is an adequate facial seal. In the presence of leaks, any type of mask may actually offer less protection independently of its nominal filtering effìciency.
Topics: Aerosols; Air Microbiology; COVID-19; Cough; Equipment Design; Evaluation Studies as Topic; Filtration; Humans; Humidity; Masks; Polypropylenes; Respiration; SARS-CoV-2; Sneezing; Temperature; Textiles
PubMed: 33258868
DOI: 10.7416/ai.2020.2390 -
Best Practice & Research. Clinical... Mar 2021We discuss the evidence behind mask use, including evidence for homemade masks, social distancing, and the local coronavirus disease-2019 (COVID-19) epidemics in... (Review)
Review
We discuss the evidence behind mask use, including evidence for homemade masks, social distancing, and the local coronavirus disease-2019 (COVID-19) epidemics in countries that initially employed more limited public health interventions. Given the absence of data for specific interventions in the rheumatic disease population, we reviewed the evidence available for the general population. The risk of poor outcomes with COVID-19 in patients with rheumatic diseases is a potential concern given the immunosuppression associated with these conditions and disease-modifying anti-rheumatic drug therapy, as well as advancing age and many of the comorbidities present in such patients. Infection prevention is key, for both individual patients and their community. Given the data collected from the general population, we recommend ongoing proper mask use, social distancing, and hand hygiene for patients with rheumatic diseases and encourage providers to counsel these patients in prevention strategies and attempt to dispel abundant misinformation.
Topics: COVID-19; Humans; Masks; Pandemics; Rheumatology; SARS-CoV-2
PubMed: 33536145
DOI: 10.1016/j.berh.2021.101663 -
American Journal of Public Health Jun 2022
Topics: Female; Gender Identity; Humans; Male; Masks; Sexual Behavior; Sexual and Gender Minorities; Surveys and Questionnaires
PubMed: 35420896
DOI: 10.2105/AJPH.2022.306834 -
PeerJ 2023Surgical masks remain a focal part of the CDC guidelines to decrease COVID-19 transmission. Evidence refuting significant effects of masking on ventilation is mostly... (Clinical Trial)
Clinical Trial
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 ( < 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 ( < 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, < 0.001. Masking resulted in a statistically significant ( < 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 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.
Topics: Humans; Child; Adult; Child, Preschool; Adolescent; Carbon Dioxide; Masks; Prospective Studies; COVID-19; Respiration
PubMed: 37342359
DOI: 10.7717/peerj.15474 -
Annals of Internal Medicine Jun 2023Optimal use of masks for preventing COVID-19 is unclear. (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Optimal use of masks for preventing COVID-19 is unclear.
PURPOSE
To update an evidence synthesis on N95, surgical, and cloth mask effectiveness in community and health care settings for preventing SARS-CoV-2 infection.
DATA SOURCES
MEDLINE, EMBASE, medRxiv (3 June 2022 to 2 January 2023), and reference lists.
STUDY SELECTION
Randomized trials of interventions to increase mask use and risk for SARS-CoV-2 infection and observational studies of mask use that controlled for potential confounders.
DATA EXTRACTION
Two investigators sequentially abstracted study data and rated quality.
DATA SYNTHESIS
Three randomized trials and 21 observational studies were included. In community settings, mask use may be associated with a small reduced risk for SARS-CoV-2 infection versus no mask use, on the basis of 2 randomized trials and 7 observational studies. In routine patient care settings, surgical masks and N95 respirators may be associated with similar risk for SARS-CoV-2 infection, on the basis of 1 new randomized trial with some imprecision and 4 observational studies. Evidence from observational studies was insufficient to evaluate other mask comparisons due to methodological limitations and inconsistency.
LIMITATION
Few randomized trials, studies had methodological limitations and some imprecision, suboptimal adherence and pragmatic aspects of randomized trials potentially attenuated benefits, very limited evidence on harms, uncertain applicability to Omicron variant predominant era, meta-analysis not done due to heterogeneity, unable to formally assess for publication bias, and restricted to English-language articles.
CONCLUSION
Updated evidence suggests that masks may be associated with a small reduction in risk for SARS-CoV-2 infection in community settings. Surgical masks and N95 respirators may be associated with similar infection risk in routine patient care settings, but a beneficial effect of N95 respirators cannot be ruled out.
PRIMARY FUNDING SOURCE
None.
Topics: Humans; SARS-CoV-2; COVID-19; Masks; Delivery of Health Care
PubMed: 37186920
DOI: 10.7326/M23-0570 -
Enfermedades Infecciosas Y... Nov 2021The global health emergency caused by the current COVID-19 pandemic is resulting in a huge challenge at all levels. The use of masks may reduce the spread of the... (Review)
Review
INTRODUCTION
The global health emergency caused by the current COVID-19 pandemic is resulting in a huge challenge at all levels. The use of masks may reduce the spread of the infection by minimising the excretion of Flügge droplets. The objective of this study was to compile the evidence available on the use of masks in relation to respiratory infections.
METHODOLOGY
An umbrella review (review of systematic reviews) was conducted. Two reviewers independently carried out the screening process, data extraction and data analysis. Discrepancies were resolved with a third reviewer, and the assessment of the risk of bias of the studies was carried out using the AMSTAR 2 tool. The Rayyan QCRI program was used for the screening process.
RESULTS
A total of eight systematic reviews were included. The studies analysed the use of masks in the general population, in long-term care facilities, in hospitals and at mass gatherings, and compared the effectiveness thereof in preventing infection. The results of this review revealed that the use of masks is associated with a protective effect against respiratory infections in healthcare facilities, in long-term care facilities and at mass gatherings.
CONCLUSIONS
In light of the results, it seems reasonable to recommend the use of masks to the general population, but this use should be accompanied by a training programme to improve compliance, as not using them properly may increase the risk of infection.
Topics: COVID-19; Humans; Masks; Pandemics; Respiratory Tract Infections; SARS-CoV-2; Systematic Reviews as Topic
PubMed: 34446392
DOI: 10.1016/j.eimce.2021.08.002 -
Medicina 2021The COVID-19 pandemic has had an impact on public health and the global economy. The objective of this document was to update, according to the available evidence, the...
The COVID-19 pandemic has had an impact on public health and the global economy. The objective of this document was to update, according to the available evidence, the management of some basic elements in the Infection Control Programs (PCI) and the daily care of patients. As a result: 1. The routine use of the N95 masks is not recommended for the care of suspected or confirmed COVID-19 patients. Available data indicates that SARS-CoV-2 has spread primarily like most other common respiratory viruses, through droplet and contact transmission. In certain situations, personto-person transmission is described through the airway, observed in poorly ventilated environments, and while the individual carried out actions of greater potential transmission 2. The limited reuse and decontamination methods of N95 masks are accepted under safe and effective prot ocols in the context of limited resources. 3. The isolation of patients with COVID-19 can be lifted under a strategy based on the clinic, individual risk factors and time of evolution of the disease. 4. PCR control is not required in confirmed cases to determine epidemiological discharge. 5. Current evidence shows that there is a possibility of reinfection although its diagnosis is difficult. 6. The measurement of antibodies has a specific role in prevalence studies, diagnosis of multisystemic inflammatory syndrome and a picture compatible with negative PCR after the 7th. day.
Topics: COVID-19; Humans; Masks; Pandemics; SARS-CoV-2
PubMed: 33906143
DOI: No ID Found -
The Cochrane Database of Systematic... Mar 2014Respiratory support is a central component of the management of critically ill children. It can be delivered invasively via an endotracheal tube or non-invasively via... (Review)
Review
BACKGROUND
Respiratory support is a central component of the management of critically ill children. It can be delivered invasively via an endotracheal tube or non-invasively via face mask, nasal mask, nasal cannula or oxygen hood/tent. Invasive ventilation can be damaging to the lungs, and the tendency to use non-invasive forms is growing. However, non-invasive delivery is often poorly tolerated by children. High-flow nasal cannula (HFNC) oxygen delivery is a relatively new therapy that shows the potential to reduce the need for intubation and be better tolerated by children than other non-invasive forms of support. HFNC therapy differs from other non-invasive forms of treatment in that it delivers heated, humidified and blended air/oxygen via nasal cannula at rates > 2 L/kg/min. This allows the user to deliver high concentrations of oxygen and to potentially deliver continuous distending pressure; this treatment often is better tolerated by the child.
OBJECTIVES
To determine whether HFNC therapy is more effective than other forms of non-invasive therapy in paediatric patients who require respiratory support.
SEARCH METHODS
We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (2013, Issue 4); MEDLINE via PubMed (January 1966 to April 2013); EMBASE (January 1980 to April 2013); CINAHL (1982 to April 2013); and LILACS (1982 to April 2013). Abstracts from conference proceedings, theses and dissertations and bibliographical references to relevant studies were also searched. We applied no restriction on language.
SELECTION CRITERIA
We planned to included randomized controlled trials (RCTs) and quas-randomized trials comparing HFNC therapy with other forms of non-invasive respiratory support for children. Non-invasive support encompassed cot, hood or tent oxygen; low-flow nasal cannulae (flow rates ≤ 2 L/min); and continuous positive airway pressure (CPAP) or bilevel positive airway pressure (BiPAP) delivered via facial or nasal mask/cannula. Treatment failure was defined by the need for additional respiratory support. We excluded children with a diagnosis of bronchiolitis.
DATA COLLECTION AND ANALYSIS
Two review authors independently assessed all studies for selection and data extraction. We used standard methodological procedures expected by The Cochrane Collaboration.
MAIN RESULTS
Our search yielded 922 records. A total of 109 relevant records were retrieved with reference to our search criteria. After duplicates and irrelevant studies were removed, 69 studies were further scrutinized. Of these, 11 studies involved children. No study matched our inclusion criteria.
AUTHORS' CONCLUSIONS
Based on the results of this review, no evidence is available to allow determination of the safety or effectiveness of HFNC as a form of respiratory support in children.
Topics: Child; Humans; Masks; Oxygen Inhalation Therapy; Respiration, Artificial
PubMed: 24604698
DOI: 10.1002/14651858.CD009850.pub2 -
Revista Brasileira de Enfermagem 2023to integrate evidence from studies on auditory perceptual and speech production effects in communication situations with face mask use. (Review)
Review
OBJECTIVES
to integrate evidence from studies on auditory perceptual and speech production effects in communication situations with face mask use.
METHODS
an integrative literature review, in MEDLINE, Cochrane Library and Embase databases. The guiding question was: what effects on communication (perceptual-auditory and speech production) occur with face mask use?
RESULTS
searches in electronic databases resulted in 1,478 studies and filtering resulted in 29 final studies.
CONCLUSIONS
mask use has effects on communication, both in perception and speech production, factors that are also related to quality of life, stress and socio-emotional factors. These data can impact on indicators and alerts in favor of adopting strategies to manage mask use, involving speech production and perception when wearing a mask in health services.
Topics: Humans; Masks; Quality of Life; Communication; Databases, Factual; Emotions
PubMed: 37820148
DOI: 10.1590/0034-7167-2022-0674