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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 -
Frontiers in Public Health 2021In the face of the novel virus SARS-CoV-2, scientists and the public are eager for evidence about what measures are effective at slowing its spread and preventing... (Review)
Review
In the face of the novel virus SARS-CoV-2, scientists and the public are eager for evidence about what measures are effective at slowing its spread and preventing morbidity and mortality. Other than mathematical modeling, studies thus far evaluating public health and behavioral interventions at scale have largely been observational and ecologic, focusing on aggregate summaries. Conclusions from these studies are susceptible to bias from threats to validity such as unmeasured confounding, concurrent policy changes, and trends over time. We offer recommendations on how to strengthen frequently applied study designs which have been used to understand the impact of interventions to reduce the spread of COVID-19, and suggest implementation-focused, pragmatic designs that, moving forward, could be used to build a robust evidence base for public health practice. We conducted a literature search of studies that evaluated the effectiveness of non-pharmaceutical interventions and policies to reduce spread, morbidity, and mortality of COVID-19. Our targeted review of the literature aimed to explore strengths and weaknesses of implemented studies, provide recommendations for improvement, and explore alternative real-world study design methods to enhance evidence-based decision-making. Study designs such as pre/post, interrupted time series, and difference-in-differences have been used to evaluate policy effects at the state or country level of a range of interventions, such as shelter-in-place, face mask mandates, and school closures. Key challenges with these designs include the difficulty of disentangling the effects of contemporaneous changes in policy and correctly modeling infectious disease dynamics. Pragmatic study designs such as the SMART (Sequential, Multiple-Assignment Randomized Trial), stepped wedge, and preference designs could be used to evaluate community re-openings such as schools, and other policy changes. As the epidemic progresses, we need to move from analyses of available data (appropriate for the beginning of the pandemic) to proactive evaluation to ensure the most rigorous approaches possible to evaluate the impact of COVID-19 prevention interventions. Pragmatic study designs, while requiring initial planning and community buy-in, could offer more robust evidence on what is effective and for whom to combat the global pandemic we face and future policy decisions.
Topics: COVID-19; Humans; Masks; Pandemics; SARS-CoV-2; Schools
PubMed: 34386470
DOI: 10.3389/fpubh.2021.657976 -
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 -
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 Paulista de Pediatria : Orgao... 2022To identify and synthesize scientific evidence that the use of face protection masks by children, in the community and at home, is a way of preventing communicable...
OBJECTIVE
To identify and synthesize scientific evidence that the use of face protection masks by children, in the community and at home, is a way of preventing communicable diseases.
DATA SOURCE
A scoping review was made using the Joana Briggs Institute method and PRISMA-ScR. A research was carried out in five electronic databases, at the Cochrane Library and on seven websites of governmental and non-governmental institutions. The data were organized in a spreadsheet and submitted to narrative analysis.
DATA SYNTHESIS
Initially, 658 productions were identified, of which 19 made up the final sample. Studies with higher levels of evidence are scarce. The types of masks identified were professional (surgical and facial respirators with filtration) and non-professional (homemade). The transmissible agents studied were influenza and SARS-CoV-2 viruses, and the evaluated environments were schools, homes and community spaces. The main discomforts reported were heat, shortness of breath, headache and maladjustment to the face. The indication and acceptability of masks change according to the age group and clinical conditions. There is no consensus on the reduction in the transmissibility of infections.
CONCLUSIONS
Children older than five can benefit from the correct use of masks, as long as they are supervised, taught and educated to do so and the masks should be well adjusted to the face. The use of masks show better results when associated with other measures such as physical distancing, keeping places ventilated and frequent hand hygiene.
Topics: COVID-19; Child; Communicable Diseases; Humans; Masks; Physical Distancing; SARS-CoV-2
PubMed: 35858041
DOI: 10.1590/1984-0462/2023/41/2021164 -
The Cochrane Database of Systematic... Apr 2016Surgical face masks were originally developed to contain and filter droplets containing microorganisms expelled from the mouth and nasopharynx of healthcare workers... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Surgical face masks were originally developed to contain and filter droplets containing microorganisms expelled from the mouth and nasopharynx of healthcare workers during surgery, thereby providing protection for the patient. However, there are several ways in which surgical face masks could potentially contribute to contamination of the surgical wound, e.g. by incorrect wear or by leaking air from the side of the mask due to poor string tension.
OBJECTIVES
To determine whether the wearing of disposable surgical face masks by the surgical team during clean surgery reduces postoperative surgical wound infection.
SEARCH METHODS
In December 2015, for this seventh update, we searched: The Cochrane Wounds Specialised Register; The Cochrane Central Register of Controlled Trials; Ovid MEDLINE; Ovid MEDLINE (In-Process & Other Non-Indexed Citations); Ovid EMBASE and EBSCO CINAHL. We also searched the bibliographies of all retrieved and relevant publications. There were no restrictions with respect to language, date of publication or study setting.
SELECTION CRITERIA
Randomised controlled trials (RCTs) and quasi-randomised controlled trials comparing the use of disposable surgical masks with the use of no mask.
DATA COLLECTION AND ANALYSIS
Two review authors extracted data independently.
MAIN RESULTS
We included three trials, involving a total of 2106 participants. There was no statistically significant difference in infection rates between the masked and unmasked group in any of the trials. We identified no new trials for this latest update.
AUTHORS' CONCLUSIONS
From the limited results it is unclear whether the wearing of surgical face masks by members of the surgical team has any impact on surgical wound infection rates for patients undergoing clean surgery.
Topics: Disposable Equipment; Humans; Masks; Randomized Controlled Trials as Topic; Surgical Wound Infection
PubMed: 27115326
DOI: 10.1002/14651858.CD002929.pub3 -
Sensors (Basel, Switzerland) Aug 2022Filter face masks are Respiratory Protective Equipment designed to protect the wearer from various hazards, suit various health situations, and match the specific...
Filter face masks are Respiratory Protective Equipment designed to protect the wearer from various hazards, suit various health situations, and match the specific requirements of the wearer. Current traditional face masks have several limitations. In this paper, we present (ME)2, the Monitoring Equipment Mask Environment: an innovative reusable 3D-printed eco-sustainable mask with an interchangeable filter. (ME)2 is equipped with multiple vital sensors on board, connected to a system-on-a-chip micro-controller with computational capabilities, Bluetooth communication, and a rechargeable battery that allows continuous monitoring of the wearer's vital signs. It monitors body temperature, heart rate, and oxygen saturation in a non-invasive, strategically positioned way. (ME)2 is accompanied by a mobile application that provides users' health information. Furthermore, through Edge Computing Artificial Intelligence (Edge AI) modules, it is possible to detect an abnormal and early symptoms linked to possible pathologies, possibly linked to the respiratory or cardiovascular tract, and therefore perform predictive analysis, launch alerts, and recommendations. To validate the feasibility of embedded in-app Edge AI modules, we tested a machine learning model able to distinguish COVID-19 versus seasonal influenza using only vital signs. By generating new synthetic data, we confirm the highly reliable performances of such a model, with an accuracy of 94.80%.
Topics: Artificial Intelligence; COVID-19; Humans; Influenza, Human; Masks
PubMed: 36080824
DOI: 10.3390/s22176365 -
International Journal of Environmental... Jan 2022Impaired flow mediated dilation (FMD), an index of vascular stress, is known after SCUBA diving. This is related to a dysfunction of nitric oxide (NO) availability and a...
Impaired flow mediated dilation (FMD), an index of vascular stress, is known after SCUBA diving. This is related to a dysfunction of nitric oxide (NO) availability and a disturbance of the redox status, possibly induced by hyperoxic/hyperbaric gas breathing. SCUBA diving is usually performed with a mask only covering "half face" (HF) and therefore forcing oral breathing. Nasal NO production is involved in vascular homeostasis and, as consequence, can significantly reduce NO possibly promoting vascular dysfunction. More recently, the utilization of "full-face" (FF) mask, allowing nasal breathing, became more frequent, but no reports are available describing their effects on vascular functions in comparison with HF masks. In this study we assessed and compared the effects of a standard shallow dive (20 min at 10 m) wearing either FF or a HF mask on different markers of vascular function (FMD), oxidative stress (ROS, 8-iso-PGF2α) and NO availability and metabolism (NO, NOx and 3-NT and iNOS expression). Data from a dive breathing a hypoxic (16% O at depth) gas mixture with HF mask are shown allowing hyperoxic/hypoxic exposure. Our data suggest that nasal breathing might significantly reduce the occurrence of vascular dysfunction possibly due to better maintenance of NO production and bioavailability, resulting in a better ability to counter reactive oxygen and nitrogen species. Besides the obvious outcomes in terms of SCUBA diving safety, our data permit a better understanding of the effects of oxygen concentrations, either in normal conditions or as a strategy to induce selected responses in health and disease.
Topics: Diving; Masks; Nitric Oxide; Oxidative Stress; Oxygen
PubMed: 35055791
DOI: 10.3390/ijerph19020965