Examining the Research for Mask Mandates
Governments around the world have been enthusiastically encouraging and mandating that we all wear masks when in public whether we’re sick or not. It seems like a logical and even patriotic thing to do, yet there is considerable backlash. Are the “anti maskers” selfish, anti science, or fringe right wingers? What does the science actually say about their efficacy and safety?
I encourage you to read the entire analysis presented here, despite it being a bit lengthy. Check my references, and come to your own conclusions. However, if it falls under TL;DR (Too Long; Didn't Read) for you, here are the main points.
• In 2020 alone, six Systematic Reviews with Meta analyses (the highest form of scientific evidence) of randomized controlled trials have shown that masks don’t stop the spread of respiratory viruses.
• Lower quality evidence being used to justify masking includes flawed experiments, observational studies that don't stand the test of time, and modeling. In the scientific community, these would never supersede the previous large body of high quality evidence that masks don’t stop the spread of respiratory viruses.
• Throughout 2020, mask mandates have not affected the infection rates or mortality curves.
• All masks, except for the tightest fitting ones, leak aerosols around the edges of the mask via "significant air leakage jets" which travel several meters up, down, and to the sides, which you can see with your own eyes in the Clear Mask Demos on the Resource Page.
• There is mixed evidence for even properly fitted N95 masks in reducing the spread of infectious aerosols and droplets. Efficacy diminishes significantly when there is not a tight seal to the face. Only 12.6% of subjects fitted them correctly even with clear instructions.
• Cloth masks have been shown to enhance the emission of fomites (infectious materials like dust particles) by 500% (yes that is 500%) and increase the risk of influenza-like illness.
• Surgeons wear masks to protect against droplets, splashes and sprays, not respiratory aerosols. If they're sick, they do not perform surgery. They also have additional oxygen piped in to the operating room to counteract the lower oxygen behind the mask.
• Asian countries have a tradition of wearing masks to prevent inhalation of pollution or transmission of droplets when they are coughing and sneezing. This is tradition, not based on research.
• With their Feb 2021 recommendation to wear two masks or a nylon stocking over the mask, the CDC essentially admits that their year long mask experiment did not work. Wearing multiple masks or stockings over the mask is unrealistic. People do need to breathe, after all.
• Wearing a mask is harmful. Masks collect microbes so well that they function as "personal bioaerosol samplers," increasing our risk of infection, reducing our oxygen levels, increasing our carbon dioxide levels with numerous serious consequences, suppressing the immune system, causing an acidic environment in the body, causing us to inhale nano fibers from the mask, causing headaches, and reducing performance. Exercising with a mask may be particularly harmful.
Broad Consensus Masks Won't Help
At the start of the pandemic, there was widespread agreement that masks won't help. Numerous experts recommended against masks for stopping the spread of SARS-CoV2. This was based on 100 years of high quality research.
Early on, Dr Fauci said that masks probably aren’t going to help protect us from covid19. President Biden’s covid adviser, Dr Osterholm, also agreed that wearing masks is “largely” nonsense and that “trying to stop the flu [another respiratory virus] is like trying to stop the wind.” In a June 2020 interview, Dr Osterholm elaborated further that masks didn't prevent or slow the pandemic in Hubei province, China in Nov and Dec 2019. Carl Heneghan testified to UK's Special Committee that cloth masks might increase risk of infection, and that, “200,000 people would have to wear a mask fully for a week to prevent one infection.” He may know what he’s talking about, as he is a British general practitioner physician, clinical epidemiologist and a Fellow of Kellogg College, director of the University of Oxford's Centre for Evidence-Based Medicine, and Editor-in-Chief of BMJ Evidence-Based Medicine.
Preponderance of the Evidence
These expert opinions were based on more than a century of research going as far back as the 1918 flu pandemic.
People were forced to wear masks in the Spanish Flu Epidemic too. When the dust settled, researchers concluded:
• "Masks have not been demonstrated to have a degree of efficiency that would warrant their compulsory application for the checking of epidemics." 
• "The evidence before the committee as to the beneficial results consequent upon the enforced wearing of masks by the entire population at all times was contradictory, and it has not encouraged the committee to suggest the general adoption of the practice." 
• “If masks are to be used they should be employed in the same manner as for protection against the plague. They should be made to cover the entire head. … It is safe to say that the face mask as used was a failure.” 
Since then, there has been a great deal of research on masks. Meta analyses and systematic reviews [1 13 46 47 82 88 ] found masks in the community won’t prevent the spread of respiratory viruses. For those who don’t know, a systematic review and meta analysis occurs when researchers gather ALL of the research on a given topic. They analyze the data from the best quality studies to see if there is a strong trend. With masks and respiratory viruses, there was indeed a strong trend - they don’t help:
• In April 2020, Jefferson, of Oxford University Centre for Evidence Based Medicine, et al's analysis showed, "Pooling of all nine trials did not show a statistically significant reduction of ILI cases (Risk Ratio 0.93, 95%CI 0.83 to 1.05) or laboratory-confirmed influenza cases (Risk Ratio 0.84, 95%CI 0.61–1.17) in the group wearing a mask compared to those not wearing a mask." 
• In April 2020, another rapid systematic review conducted by Brainard, et al corroborated these findings, "The evidence is not sufficiently strong to support widespread use of facemasks as a protective measure against COVID19." 
• In May 2020, in Emerging Infectious Diseases, Xiao, et al concluded, “We did not find evidence that surgical-type face masks are effective in reducing laboratory-confirmed influenza transmission, either when worn by infected persons (source control) or by persons in the general community to reduce their susceptibility.” 
• May 2020 The University of Edinburg Usher Institute Systematic Review that found , “This review found mixed and low quality epidemiological evidence on the use of face masks to prevent community transmission of respiratory illness,” and, “Based on the epidemiological evidence, the effectiveness of face masks has not been demonstrated." 
• September 2020 meta analysis  that also concluded, "Surgical mask wearing among individuals in non-healthcare settings is not significantly associated with reduction in ARI [acute respiratory illness] incidence in this meta-review."
• The massive November 2020 systemic review of 67 studies conducted by the independent Cochrane Collaboration that also concluded, "Pooled results from randomized trials did not show a clear reduction in respiratory viral infection with the use of medical / surgical masks during seasonal influenza. There were no clear differences between the use of medical / surgical masks compared to N95 / P2 respirators in healthcare workers when used in routine care to reduce respiratory viral infection." 
With this many systematic reviews and meta analyses in agreement, we can have great confidence that masks do not prevent respiratory viruses from spreading in a community setting. Because of that, you could just stop reading here. But the story continues because whoever is interested in masking the community has spent a great deal of money to promote the idea that masks work with lower forms of evidence, biased papers, plenty of spin, and indoctrinating the public.
Drs Fauci and Osterholm were also well aware of the many studies [2 3 4 5 6 7 8 9] that were done with surgeons with and without masks. Most of them concluded that surgeons wearing masks won’t prevent wound infections. One study even put a tracer particle (albumin microspheres) on the inside of the surgeon’s mask . Guess where those microspheres ended up… you guessed it! The surgical wound. They got blown out the sides of the mask into the air, and into the wound directly in front of them. In Clinical Orthopedics, Ritter  blames redirected airflow, “The wearing of a surgical face mask had no effect upon the overall operating room environmental contamination and probably work only to redirect the projectile effect of talking and breathing.” Indeed, a 2021 study in Engineering in Medicine and Biology  backed up that astute observation, concluding that, "surgical and handmade masks, and face shields, generate significant leakage jets that may present major hazards... The effectiveness of the masks should mostly be considered based on the generation of secondary jets rather than on the ability to mitigate the front throughflow."
Masks might even make the wound infections worse. In Anesthesia and Intensive Care, Skinner and Sutton  wrote, “There is little evidence to suggest that the wearing of surgical face masks by staff in the operating theatre decreases postoperative wound infections. However, there is evidence indicating a significant reduction in post-operative wound infection rates when theatre staff are unmasked.” [emphasis mine]
In March 2020, the Journal of the American Medical Association made the following recommendation , “Face masks should be used only by individuals who have symptoms of respiratory infection such as coughing, sneezing, or, in some cases, fever,” and “Face masks should not be worn by healthy individuals to protect themselves from acquiring respiratory infection because there is no evidence to suggest that face masks worn by healthy individuals are effective in preventing people from becoming ill.”
In May 2020, the New England Journal of Medicine, weighed in  with this, “We know that wearing a mask outside health care facilities offers little, if any, protection from infection.” This was all confirmed in a September 2020 meta review  published in Frontiers in Medicine that concluded, “Surgical mask wearing among individuals in non-healthcare settings is not significantly associated with reduction in ARI incidence in this meta-review.”
Adding to the consensus that masks don't stop respiratory viruses were two lawsuits  between the Ontario Nurses Association and the hospitals from the Toronto Academic Health Science Network (TAHSN) regarding masks in 2015 and 2018. The hospitals instituted a policy that nurses either had to receive the influenza vaccine or wear a mask for their entire shift. In both lawsuits, after reviewing the data, the arbitrators found the mask policy to be “illogical,” “the exact opposite of being reasonable,” and that there is “scant evidence” that forcing nurses to wear masks reduced transmission of influenza.
Governments Ignore Overwhelming Data in Favor of Mask Mandates
So we started 2020 with an immense body of data concluding masks don’t stop the spread of viruses, including meta analyses, numerous studies with surgeons, medical and legal opinions. Despite this huge body of evidence, our government told us we should wear masks inside when we can’t social distance. This initial precaution is understandable because masks can catch the large droplets (>5 µm) emitted when someone coughs, sneezes, or talks. (This is in fact the reason surgeons wear surgical masks – so their saliva doesn’t end up in the wound and so they don’t get splashed by fluids.) Droplets are relatively large and heavy, causing them to drop to the ground pretty quickly, usually within 1 or 2 meters. This is the rationale for “social distancing”; our spittle is unlikely to reach each other when we’re further than 1 or 2 meters apart. If you can’t social distance, a mask will help you to avoid accidentally getting your saliva droplets on someone else, or theirs on you. This of course ignores the impact of smaller, lighter aerosols, the main mode of transmission of SARS-CoV2.
The Mask Mandates Broadened
But then things got weird. We were instructed (i.e. mandated) to wear masks inside even when we can social distance, without any high quality scientific justification. Soon, the mandates went even further, directing us to wear masks outside, and then even when we can socially distance outside. In some areas, people are fined for going anywhere outside of their house without a mask. In February 2021, when it became obvious that masks did nothing to stop the spread, the CDC officially recommended that we wear two masks and even a nylon stocking over the mask ensemble . It has been suggested that we wear masks even when having sexual intercourse. No joke . When will it end?
Do We Even Catch SARS-CoV2 Outside?
A systematic review  couldn’t find any solid evidence of outdoor transmission when people weren’t also going inside together.
A study from China found that only 1 transmission may have occurred outside out of the 318 outbreaks it analyzed. It is exceedingly difficult to pinpoint a single outdoor transmission during an outbreak where many people are infected, especially in light of false positives of PCR tests using high cycle thresholds. Finding uncertain evidence of a single transmission in the context of over three hundred outbreaks that include many infected people, casts doubt on whether that one transmission actually occurred outdoors.
Computer modeling  concluded that some weather conditions might favor outdoor contraction, but that has not occurred. The covid models have been disturbingly incorrect. For example, the initial catastrophic predictions by Neil Ferguson, the disease modeller with the MRC Centre for Global Infectious Disease Analysis, for the death toll in Sweden with no lock downs and masks was about 10 times higher than what actually happened.
Although outdoor transmission is acknowledged as being theoretically possible with models, there is no concrete evidence. The preponderance of the evidence says that you are highly unlikely to contract the coronavirus outside, because of air currents and infinite dilution of the viral particles. Among the millions of confirmed cases, there’s no real evidence of outdoor transmission, just fear. Wearing masks outside under normal circumstances is particularly unjustified.
How Did We Get Here?
In a few months, we went from the scientifically backed consensus that masks don’t prevent the spread of respiratory viruses to wearing masks outside even when you’re not near anyone.
Almost all of the mask studies published 1921–2021 concluded that masks don’t stop respiratory infections, evidenced by meta analyses like the ones referenced earlier. If masks were even moderately effective at reducing the risk of infection, a benefit would have been statistically detected in these high quality previous large studies.
Then masks became political, and what seems like out of thin air, came a handful of highly promoted new studies and models that are vigorously in favor of using masks to prevent the spread of respiratory viruses.
The divergence between the old data and these new studies is remarkable, and should be considered with caution. Even more remarkable is how these weaker studies are being emphasized. This is cherry picking at its finest. Let's take a look at these new pro mask studies.
Research Used to Justify Mask Mandates
The researchers in some of the new mask studies do actually state that masks help, but you need to read the fine print. They have poor experimental design, confounding variables, significant missing data, “low certainty” of evidence, and are the lowest form of scientific evidence . One was even retracted  and there are numerous calls for retractions of the Lancet mask paper  and another by the National Academy of Science . Speaking of fine print, even the World Health Organization enthusiastically recommends masks to the public, but they acknowledge on the health professional page , “At the present time, the widespread use of masks by healthy people in the community setting is not yet supported by high quality or direct scientific evidence.”
Similarly, politicians telling everyone to mask up, cancel events, and hunker down are caught attending large private social events with no masks (like CA governor Gavin Newsom and Dr Birx). Dr Fauci has even been seen on camera in public indoor locations with his mask under his chin. If they really believed their mandates, wouldn’t they follow them too?
After reviewing most of the studies, the only statistically significant data on preventing viral spread is potentially for properly fitted N95 masks. These leak fewer aerosols (at least according to what we can measure) and have better filtering capability than other masks. But during 2020, we were told to reserve these for healthcare workers (as we should) and wear other types of masks, which we did. There has been very high mask wearing in most of the United States , even outside not near others.
When that didn't work, in an unintended admission of defeat, early 2021, there have been calls for double masks, nylon stockings over masks, and N95s for all . Although N95s would be expected to help, the N95 mandate in Germany did not stop the major increase in cases after the mandate went into effect.
Even with an N95, proper fit is paramount. In medical settings, they are professionally fit tested. When they are not fitted, their efficacy goes dramatically down. According to research published in Journal of the American Medical Association , only 12.6% of subjects in a community setting properly fitted their N95 mask, despite visual and written instructions. When data from Drewnick et al's paper in Aerosol Science and Technology  is extrapolated, only a 3.2% leakage area brings mask efficacy down to zero.
Let's now take a look at the studies most often being used to “prove” masks stop respiratory virus transmission. As you will see, they have significant weaknesses and are lower quality of evidence . We should keep in mind that the highest quality of evidence is the meta analysis . In science, a few lab experiments or a single meta analysis would never replace even one, much less many, meta analyses that came to a different conclusion.
A Mix of Interventions
In this one pro mask, outlier meta study published in the Lancet  researchers looked at different interventions (like masks, social distancing, and hand hygiene) on stopping the spread of the coronavirus. The authors of the study state that all of these interventions happened together, but somehow still concluded that masks were helping, even though they can’t legitimately make that claim since there wasn’t data with just masks. This issue of "multicollinearity" is like saying, “Lucky Charms are part of this complete breakfast.” Even the studies included in the meta study did not attempt to separate the effects of individual variables in a regression analysis. This study exemplifies the old adage, "garbage in, garbage out." Furthermore, the studies they examined involved health care workers. They cannot extrapolate any results to the community setting, where people aren't trained and are unlikely to use proper protocols for PPE [personal protective equipment]. To their credit, the authors rated their evidence on masks as “low certainty.” Yet this study is being held up as “proof” that masks work. Since when is “low certainty of evidence” sufficient to mandate interventions that affect people’s health?
Due to many egregious flaws in this study, there are calls for its retraction  claiming that the report is "riddled with data errors" and "weak science based on weak science." I highly recommend that you read Gutmann's detailed review  with a critical look at studies that were included and the flaws in their mathematical analysis.
Blowing into a Box
Other research conducted at UC Davis  and Duke  “proving” masks help had participants blow into a tube or a box with and without various masks or directed airflow through a tube. If fewer particles were emitted from the front of the mask, they deemed that mask to be effective. Which makes sense, except when you consider the aerosols and leakage around the sides of the mask. Studies like these only measure the forward projection of larger particles. They are unable to measure the plumes out the edges of the mask or the very small particles called aerosols (<5µm), which can contain live virus.
• Leakage Jets. Because most masks don't make a tight seal to your face, aerosols are continuously escaping from the top, bottom, and sides of your mask. Viola et al warn , "Surgical and handmade masks, and face shields, generate significant leakage jets that may present major hazards." This is what causes your glasses to fog up. The leakage jets were well demonstrated in this short video. The leakage occurs even with an N95 mask if it's not properly fitted, a process done by professionals in a medical setting. Research has shown that almost 90% of the community would not wear an N95 correctly, even with written and visual instructions , so leakage jets will be an issue with most N95s as well.
• Particle size. Because of limits of detection, the number of particles emitted out the front of the mask were probably underestimated. The Duke study  concedes that they were unable to measure particles smaller than 0.5 µm. Viral particles can be as small as 0.01 to 0.1 µm, smaller than tobacco smoke . If you can smell cigarette smoke through your mask, you can inhale desiccated aerosols through your mask, as well as in around the edges. Some masks (like a bandana) nebulized larger particles into many more smaller particles , increasing the number of smaller particles which stay floating in the air for hours. All masks are likely nebulizing droplets into smaller particles, but these particles are being missed due to the analytical limit of detection.
The average infected person sheds 187 viral copies per minute , with some shedding as more than 20,000 viruses in 20 minutes . It doesn't take much to get infected. Based on research for SARS-CoV , the infectious dose estimated to infect 50% of people exposed (ID50), is probably around 130–530 viral particles (expressed as PFU or plaque forming units). With so many aerosols escaping out the edges and front of the mask with every breath, it's pretty clear why masks haven't made a dent in infection rates anywhere.
Hamsters in Cages
In another study, researchers thought it would be a realistic experiment to put hamsters with covid in one cage  next to hamsters without covid in another cage. They separated the cages with a hole. In one experiment, they left the hole open. In follow up experiments, they covered the hole with a mask, facing either toward the infected hamster or away from it.
• The presence of the mask seemed to result in fewer infections, however the p-values were very high (indicating weak evidence) and the results were not significant.
• On top of that, odds are that the mask was very well attached to the side of the cage, with no airflow out the edges of the mask. When we wear a mask on our faces, there is plenty of airflow out the edges.
• The masks also had a fan blowing on them, so they were nice and dry, not moist like the ones we wear for hours. Moisture can affect the filtering efficiency of the mask, resulting in increased emission of viral particles. All of the different mask experiments had the same problem.
Again, another unrealistic study, lacking statistical significance, being held up as proof that masks help.
Mannequins in a Box
The experiment carried out by Virginia Tech  is the most impressive experiment in its attempt to simulate mask wearing in real life. They put mannequin heads in an enclosed box, with one head breathing out aerosols and droplets and the other breathing in, with various mask types and configurations. While it did show variable reduction in particles getting through the mask on both the exhale and inhale, there are some significant limitations. 1) The heads were only 13 inches apart. So this simulation only applies to very close contact, which is not in dispute. 2) The heads were enclosed in a very small space, which is unrealistic. 3) Since they only ran each experiment for 30 seconds, they would have totally missed the effect of moisture accumulation after a few hours in the real world, which affects performance. Of note, it also found better aerosol filtering for hydrophobic materials. 4) The authors acknowledge that the mannequins don’t account for different head shapes or the effect of disruption of the plenum that happens in a human that’s both inhaling and exhaling. So as good as this one is, it has likely overstated the benefits of masks as well and does not apply to speaking when socially distancing or in normal sized rooms or outdoors.
The Case of the Masked Hairdressers
Moving on to observational reports... One of the early case studies to prove masks work involves two hair dressers who were symptomatic and tested positive for covid19 . Both wore masks while working. This study reports that “none” of the 139 clients got coronavirus, and is presented as strong evidence that masking helps prevent transmission. Of course, there are some problems with this. First, only half of the clients agreed to get tested. So the status of 50% of the clients is unknown. Second, another large portion of the clients were not included – those who were in contact with the stylists when their viral load could have been high (immediately before symptom onset). Third, the hairdressers obviously had mild cases, otherwise they wouldn’t have been able to or allowed to work. In this day and age, literally no one would stay near someone who is coughing or sneezing. If this is evidence of anything, it’s that you’re less likely to spread the virus when you have a mild or asymptomatic case. Again, you cannot reasonably conclude that masks work from this small, incomplete case.
There’s No Place Like Kansas
Researchers were eager to correlate fewer infections with mask mandates, like this comparison in Kansas . A small percentage of the counties adopted the governor’s optional mask mandate. They were the most populated areas. The rural areas didn’t adopt the mandate.
The places that adopted the mandate had 1 case less per 100K after the mandate went into effect. The benefit of masks here is… underwhelming, not to mention not statistically significant, especially when factoring in the unreliability of PCR tests. Areas that didn’t adopt the mandate still had 25% FEWER cases than the areas with a mandate. Any trend of slowing infections that they observed likely had nothing to do with masks, and more to do with how the virus spreads through densely populated areas first followed by rural areas, something we’re seeing all over the country.
Additionally, the trends didn't hold, even at the time of publication of the research, as Youyang Gu, an independent data scientist out of MIT, stated on Dr Vinay Prasad's podcast.
The Effect of Mandates in Other States
Two additional analyses attempted to correlate mask mandates with reducing cases  and hospitalizations .
In August 2020, Lyu, et al  reported that mask mandates slowed the rate of spread by a maximum of 2% between March 21st and May 22nd, 2020 in various states. Of note, the data was examined for the springtime, when respiratory infections naturally decrease due to warmer weather, more humidity, and people getting outside. So maybe the underwhelming 2% slowdown of the rate of increase was not due to masks, but due to the weather or other measures put into effect simultaneously.
In February 2021, the CDC's Morbidity and Mortality Weekly Report (MMWR) indicated  that, "Statewide mask mandates reported a decline in weekly COVID-19–associated hospitalization growth rates by up to 5.6 percentage points for adults aged 18–64 years after mandate implementation, compared with growth rates during the 4 weeks preceding implementation of the mandate." This analysis also used data from spring, summer, and early fall (March–October) when people are outside, getting vitamin D, and more often avoiding indoor spaces where transmission would occur. The CDC also used selected areas within states (instead of the entire state), a less accurate regression analysis (OLS vs the more accurate ODR), confounding factors, and additional evidence that showed no effect of mask mandates in other countries. For more details, see the American Institute of Economic Research's thorough analysis .
Either way, the reason for the slowdown doesn't need to be debated because every state with higher and higher mask compliance still had skyrocketing cases and hospitalizations when the cold weather returned. You can prove this to yourself by googling [the state you're interested in] and covid cases or checking out the many graphs available online that show when a mask mandate went into effect like this one, and the cases that follow in the state or country. For obvious reasons, these are only found on politically conservative sites. Politics aside, every time, the mask mandate did not prevent a seasonal rapid rise in cases after the mandate.
I’ve witnessed this with my own eyes in Boston. Since early spring, everyone in the city was wearing masks, even outside, even late at night alone on a deserted street, even without the governor’s mandate. And yet we still had a casedemic. Then came the widely publicized paper  that concluded there were reduced hospitalizations after mask mandates. But it had to be withdrawn because unfortunately, the hospitalizations increased even after the mandates went into effect. The media failed to update us about the withdrawal.
They also failed to update us about these more recent studies:
• A May 2021 analysis  that concluded, "Mask mandates and use are not associated with slower state-level COVID-19 spread during COVID25 19 growth surges,"
• The September 2021 analysis of mask mandates in Texas counties  that found, "no reduction in per-population daily mortality, hospital bed, ICU bed, or ventilator occupancy of COVID-19-positive patients attributable to the implementation of a mask-wearing mandate."
The virus spreads at different rates in different areas, with or without mask use. The only thing you can count on is that it spreads.
Worldwide Analysis of Mask Policies
The authors of a worldwide analysis  report that countries that adopted widespread use of masks early had less covid19 mortality. However, the countries with early masking were mainly Asian countries who have higher exposure to SARS type viruses, better overall health, and a different microbiome than westerners, as well as governments with more stringent pandemic mitigation measures. The issue of multicollinearity shows up here too.
Interestingly, the authors glossed over the Scandinavian countries and didn’t mention the total mortality in those countries at all. Norway and Finland have very low use of masks and have among the lowest covid death toll. Sweden’s death toll was higher at first, mainly due to shared ski vacations with Italians when the pandemic began. For many months, Sweden had negative excess mortality by as much as 10%, despite no masks or lockdowns.
A better measure of whether masks help would be to determine whether masking reduces infection after mandates were implemented. Carl Heneghan stated that infections continued to increase in England after mask mandates, despite the expectation that infections would go down by 40%, based on modeling (which like all covid models, was incorrect).
More Inaccurate Modeling
The Institute of Health Metrics Evaluation (IHME) published a study  in October 2020 claiming that if Americans could increase mask usage from the “current” 49% to above 80%, we could save 130,000 lives. NIH Director Francis Collins along with 100 media outlets widely publicized the study, fomenting the mask frenzy. However, their model was based on faulty data. In their analysis, the authors assumed 49% average mask usage in the US. But Phillip W. Magness of the Wall Street Journal pointed out in his article  that 80% of Americans were already wearing masks regularly since the summer, based on surveys done by Carnegie Mellon and the YouGov/Economist. So we were already at the end point of that study, and still have skyrocketing cases. Magness contacted the authors for clarification. The authors responded with a statement that the inconsistency was “immaterial.”
National Academy of Spin
In January 2021, the National Academy of Science (NAS) published their own review of the mask data . This section will be a more in depth review because anything published by the National Academy of Science may carry more weight. Although one would expect any reports by the NAS to be unbiased and fairly present the data, this paper was heavily biased in favor of community masking. For example, the authors:
• Cherry picked pro mask statements from other reviews and analyses that did not support community masking
• Stated trials with influenza don't apply to SARS-CoV2 while using trials with bacteria — a whole different species — to support masking in the current pandemic
• Emphasize lower forms of evidence like modeling in lieu of the highest forms of scientific evidence like meta analyses of randomized controlled trials
• Left key studies out of their paper
• Put forth completely unrealistic mask designs that no one in the community would tolerate
• Completely ignore the harms of masking
Details are below.
Meta analyses of randomized controlled trials are considered the highest form of scientific evidence, because they synthesize data from all of the best quality, most relevant studies. As mentioned in other sections above, there were 6 meta analyses and systematic reviews in 2020 that concluded masks do not prevent the spread of respiratory viruses [1 13 46 47 82 88 ].
Naturally, NAS authors started out mentioning a few of the meta analyses and randomized controlled trials, all of which confirmed that there is little evidence for masks in preventing the spread of respiratory viruses. Interestingly, they chose to highlight a few of the more positive statements from the studies to give the impression that they are in favor of community masking.
• They shared this quote from the Cochrane review , “Overall masks were the best performing intervention across populations, settings and threats.” If you read that, you would think that the Cochrane review supported community mask use. The review does include a lot of pro mask verbiage, but in the end, this is what they report their data actually showed, “Pooled results from randomized trials did not show a clear reduction in respiratory viral infection with the use of medical / surgical masks during seasonal influenza. There were no clear differences between the use of medical / surgical masks compared to N95 / P2 respirators in healthcare workers when used in routine care to reduce respiratory viral infection."
• The NAS authors quoted the Usher Institute paper  with, “Homemade masks worn by sick people can reduce virus transmission by mitigating aerosol dispersal,” and, “Homemade masks worn by sick people can also reduce transmission through droplets.” Again, these quotes would lead the unsuspecting reader to conclude the Usher Institute’s analysis found benefit to community masking. But their actual conclusion was, “This review found mixed and low quality epidemiological evidence on the use of face masks to prevent community transmission of respiratory illness,” and, “Based on the epidemiological evidence, the effectiveness of face masks has not been demonstrated."
They could have left it at that, but apparently, lack of benefit of community masking wasn’t the conclusion they were looking for. So they went on to explain that the traditional gold standard of medical evidence doesn’t apply to masks and that weaker forms of evidence like mechanistic experiments, observational studies, and models will more accurately demonstrate how effective masks really are.
The authors then went on to say that conducting randomized trials would be unethical in a pandemic. Perhaps they didn’t see the Danish mask study  that showed no difference in infection rates between 3000 participants who wore masks and 3000 participants who didn’t wear masks, the CDC report  that found those who reported always wearing masks got infected just as often as those who didn’t, and the many charts with the same infection rates in counties, states, and countries with and without mask mandates.
Curiously, the authors also state that, “None of the studies looked specifically at cloth masks.” But McIntyre, et al , found that health care workers who wore cotton facemasks suffered from significantly more respiratory illness than those who wore surgical masks, and concluded that, “Moisture retention, reuse of cloth masks and poor filtration may result in increased risk of infection.” Later in the paper NAS authors mention that this study is misinterpreted because it was done in a hospital setting, where presumably viruses act differently. They also neglected to mention the research  that showed cloth masks emit 500% more fomites than no mask, which would therefore make someone 500% more infectious than breathing without a mask.
One of their complaints about the current randomized trials is that they were mostly conducted with influenza, SARS, and MERS, and not specifically SARS-CoV2. But later in the paper, they cite several flawed experimental studies to support masking with other viruses and even bacteria like tuberculosis and Pseudomonas aeruginosa [90–96]. This is hypocritical, and clear evidence of spin. Meta analyses that studied masks with respiratory viruses are certainly more applicable to SARS-CoV2 than experiments with a whole different species, like bacteria.
The mechanistic studies failed to account for important characteristics mentioned in the sections above like hazardous leakage jets around the edges of the mask, which allow infectious aerosols to escape into the environment. Many only measured the breath from the front of the mask [97-99].
Unsurprisingly, Milton  found that masks are much better at filtering large particles. Surprisingly, they found that fine particles contain nine times more viral particles than larger droplets, which are the ones more likely to escape the mask.
The experiment done specifically with SARS-CoV2 that they cite as evidence of benefit of community masking was the totally unrealistic experiment with hamsters in cages  discussed above (see section "Hamsters in Cages").
The NAS authors presented Davies et al research  as evidence that “homemade masks filter a high percentage of particles” but Davies actual conclusion was, “We would not recommend the use of homemade face masks as a method of reducing transmission of infection from aerosols.” In yet another misleading citation, NAS authors reference Viola et al  in their statement, “It has been shown that all kinds of masks greatly limit the spread of the emission cloud.” But Viola is the researcher who very clearly called attention to the hazardous jet streams when they wrote, “Surgical and handmade masks, and face shields, generate significant leakage jets that have the potential to disperse virus-laden fluid particles by several metres.” Viola also calls into question the validity of only measuring forward projection of aerosols, “Our results suggest that the effectiveness of the masks should mostly be considered based on the generation of secondary jets rather than on the ability to mitigate the front throughflow.” The reduction in particles projected forward is the evidence NAS relies on to assert that masks are effective for reducing transmission.
NAS authors also referenced Verma et al’s research  in their claim that a stitched mask was effective for reducing jet distance in all directions, and conveniently leave out Verma’s warning, “However, leakage remains a likely issue for members of the general public who often rely on loose-fitting homemade masks. Additionally, the masks may get saturated after prolonged use, which might also influence their filtration capability.” It is unlikely that the general public will tolerate tight fitting masks like N95s that cause headaches and other issues in health care workers.
As for using masks as PPE (rather than source control), instead of discussing the Danish mask  and CDC studies  mentioned above that showed equal risk of infection between masked and unmasked people, they cite a few papers with completely unrealistic and suffocating ideas for improving efficacy like:
• The literal face diaper with 8 cotton layers, which even the authors acknowledge might be hard for people to breathe in . Check out the photo in the paper if you have time, and imagine anyone actually wearing that.
• Rubber bands connected to a face shield and paper clip in the back of the head .
• “Silk covering for the whole head (and flannel sewed over nose and mouth areas), with holes for the eyes, tucked into the shirt." .
Judging from the number of people “double masking” at the present time, some subset of the population might attempt ideas such as these for a while, but none of this is realistic in the wider community as they appear to be torture devices.
After sharing their unusual take on randomized trials and meta analyses, NAS authors go on to cite observational studies with significant issues like the worldwide analysis discussed above  and various models.
Dr Sunetra Gupta, Oxford Professor of Theoretical Epidemiology, has been warning of the dangers of disease modeling for decades. She writes, “Although we now have at our disposal some fairly sophisticated methods of characterizing uncertainty, these do not actually enable us to control or even predict the extent of the disaster. Used injudiciously in these circumstances, mathematics – and especially mathematical modelling – can serve to obfuscate rather than clarify, or at best add nothing at all to the situation other than the illusion of control.” The modelling for covid19 has been especially misleading, resulting in mitigation policies that caused catastrophic harms to the world’s population. Real world data is far more reliable than models, which can be even more easily adjusted to show the desired result.
The authors attempt to show additional non-aerosol related benefits to mask wearing.
• First they state, “One possible additional benefit of masks as PPE is that they do not allow hands to directly touch the nose and mouth, which may be a transmission vector.” But they neglect to mention all the handling and constant adjustments of the uncomfortable, contaminated masks which are so covered in microbes, they can be used as "personal sampling devices" in hospital infectious disease research. Handling the mask logically contributes to spreading of microbes. Oddly the authors state there is no “laboratory evidence” of self contamination. But previous research that they cited elsewhere in the paper highlighted mask contamination as a problem .
• They then go on to state that masks are a “visible signal and reminder of the pandemic.” For this purpose, the constant, dire media coverage was sufficient, without subjecting the public to the risks of masking (see "Masks Might be Making Us Sick" below).
• The authors also indicated that if everyone is made to wear masks, those who desire to do so won’t be stigmatized. Because a small number of people are scared enough to do something unscientific and harmful, we all should?
The NAS authors recommend further study on different materials and the issue of self contamination, especially after kids wearing them all day at school or adults all day at work. They completely left out legitimate concerns about inhaling nano and micro fibers , lower oxygenation, hazardous jet streams, the impact on immunity, changes to the oral microbiome, and the psychological impact especially on developing children.
Besides the report discussed here, there are calls for retraction of another National Academy of Science paper  that extolled the benefits of masking. Forty medical experts petitioned  for its retraction stating, "The claims in this study were based on easily falsifiable claims and methodological design flaws. We present only a small selection of the most egregious errors here. Given the scope and severity of the issues we present, and the paper’s outsized and immediate public impact, we ask that the Editors of PNAS retract this paper immediately and reassess the Contributed Submission editorial process by which it was published."
I would suggest that we stop wasting time and money trying to disprove the preponderance of evidence that masks don’t block transmission of respiratory viruses and instead invest those resources in something more promising. We should also assess the “potential erosion of trust in science” discussed by Martin et al  and government due to intrusive and harmful mandates lacking excellent scientific justification.
Let Them Wear Masks
Hopefully it's becoming increasingly evident to you that the science being used to justify community masking is all smoke and mirrors. Dr Monica Gandhi, known as the mask queen, deserves special mention. She penned a flurry of pro mask decrees in 2020, and shows no sign of slowing down on her mission to mask the populace. I keep finding really strange things whenever I check her references. There are many instances where her references don't support the statements she makes, but anyone casually reading without checking the references would be under the impression that all of the references support masking.
Here’s one sterling example. In one paper , she wrote, “A systematic review of physical interventions to reduce the spread of respiratory viruses for the public showed that surgical masks are the most consistent and comprehensive measure to interrupt transmission, because N95 masks can irritate the skin and thereby reduce compliance [16, 44].” If you read that sentence, you’d think that surgical masks have been proven to stop viral transmission and it's the best thing we can do to stop the spread, even if it's not the N95 mask. But the references she shared don’t support her statement.
• Ghandi's reference #44 made me laugh out loud . This one is about how to get people to believe in using masks through government propaganda. This is the title: “The use of facemasks to prevent respiratory infection: a literature review in the context of the Health Belief Model.” Here’s their conclusion: “We found that individuals are more likely to wear facemasks due to the perceived susceptibility and perceived severity of being afflicted with life-threatening diseases.” They recommended, “Media blitz and public health promotion activities supported by government agencies provide cues to increase the public's usage of facemasks.” In their conclusion they say, “Further studies are required to evaluate the effectiveness of implemented interventions.” So they’re discussing how to get the government to scare you enough to wear masks, and then conclude that we should probably see if they’re even effective. THAT'S EXACTLY WHAT HAPPENED IN 2020! They scared everyone into submission, emphasized masks everywhere you go, even on the highways, and then tried to drum up some studies to prove masks were effective.
• Her reference #16 is to the systematic review in November 2020 that specifically concluded, “Pooled results from randomized trials did not show a clear reduction in respiratory viral infection with the use of medical / surgical masks during seasonal influenza. There were no clear differences between the use of medical / surgical masks compared to N95 / P2 respirators in healthcare workers when used in routine care to reduce respiratory viral infection.”  Of course you have to read through even their politically correct verbiage to get to that statement, but that is what their data showed, yet she used this statement to support the belief that masks work.
Zooming back out... remember that references 16 and 44 were used by Dr Gandhi to give the impression that "masks are the most consistent and comprehensive measure" for preventing transmission. This one example of many demonstrates what appears again and again in the pro mask papers — layer upon layer of misrepresentation in the pro mask “science.”
When Did the Science Bar Get So Low?
Prior to covid19, strong evidence gathered over 100 years demonstrated that masks don’t stop the spread of respiratory viruses. Remarkably, many of the studies conducted during this pandemic directly contradicted the preponderance of the existing evidence. Several times their conclusions did not reflect what the data actually said. Across the board, they suffered from low certainty of evidence, problematic experimental designs that ignore the jet stream of aerosol leakage around the edges of the mask and the effect of moisture, inaccurate modeling, confounding variables, and incomplete/old data. One was retracted and there are numerous calls in the scientific community to retract the Lancet study. Regardless, these studies are consistently marketed as evidence that masks will prevent 40% of covid cases or save over 100 thousand lives, which has also been disproven. This is not policy grade evidence, yet it is what our government is using as a basis to mask the entire population.
Additionally, they’re completely ignoring the new evidence that continues to roll in:
• September 2020 meta analysis  that also concluded masks don’t help prevent respiratory illness.
• The large November 2020 Danish randomized controlled trial  where there was no significant difference in infections between the 3000 participants who wore masks and the 3000 who didn’t.
• The massive November 2020 systemic review of 67 studies conducted by the independent Cochrane Collaboration that also concluded masks don't stop respiratory infections .
• The University of Edinburg Usher Institute Systematic Review that found no benefit to community masking .
Why are these studies excluded from consideration with regard to mask mandates? It does not appear that our government is following the science.
The same pattern of extreme bias and problematic papers being published by medical journals is also occurring in other areas related to the pandemic. Notable examples include:
• The Lancet paper  discrediting hydroxychloroquine as a safe and effective treatment for Covid19 was retracted after scientists discovered that the data on which the analysis was based was provided by a fraudulent company called Surgisphere, run by an adult entertainer and science fiction writers. How did this questionable data source get past the authors and peer review process of the Lancet?
• The Nature paper  discrediting the SARS-CoV2 lab leak theory, published weeks after the lead author Kristian Andersen emailed Dr Fauci, "Look really closely at all the sequences to see that some of the features (potentially) look engineered." Dr Andersen also wrote, "I should mention that after discussions earlier today, Eddie, Bob, Mike, and myself all find the genome inconsistent with expectations from evolutionary theory." Eddie and Bob were co-authors on the paper discrediting the lab leak theory. The email exchange was obtained through the Freedom of Information Act.
• Publication of the randomized controlled trial  that found no benefit of mask wearing on SARS-Cov2 infection was delayed for months. The authors said that it would be published when the journals were "brave enough" to do so.
• Tess Lawrie, lead Cochrane researcher, experienced road block after roadblock in publishing her meta analysis that showed ivermectin is effective in preventing covid19 . It was finally published in June 2021. Thousands of lives could have been saved if it was released months earlier.
When did the science bar get so low, especially for a pervasive intervention being forced on the entire population? Why are our top government health officials ignoring this fact?
Masks Might be Making Us Sick
Compounding the problem is the concern that masks might be making us sick in other ways. It's possible that our "cures" are worse than the original problem. Masks may actually be enhancing the spread because cloth masks release more fomites than no mask, all masks create hazardous jet streams out the edges of the mask, masks are the perfect warm, moist, breeding ground for bacteria, fungi, and viruses. On top of that, masks release nanofibers that we breathe deep into our lungs. There is abundant evidence that mask wearing disrupts blood oxygen and carbon dioxide levels with long term consequences, of immediate concern for anyone exercising. These topics are discussed in more depth below with references.
Cloth Masks Spread 500% MORE Fomites Than No Masks
The previously mentioned pro mask study from Nature  where subjects breathed into a tube found that some cloth masks emit 500% MORE fomites than no mask. That is not a typo – five hundred percent more particles. Fomites are infectious surfaces. In this case, fomites are dust particles that transport live viruses. Infectious virus can live on dust particles as shown in previous research . The dramatic increase in fomites emitted from the mask of an infectious person will carry live virus and actually increase the spread, the opposite of what we’re trying to do.
We're Inhaling Fibers and Chemicals
Of equal concern, if you’re creating dust particles by breathing OUT with a mask, you’re also breathing IN these dust particles at extremely high rates. Mask wearing causes us to breathe more deeply to make up for the lack of oxygen , increasing the chance of dust particles dislodging from the mask and traveling into our lungs.
Indeed, researchers have found respirable plastic and fibrous debris on the inside of masks in the micron and sub micron range, and are concerned that we are breathing these fibers in , causing "stress and inflammation in the human respiratory tract and exacerbate vulnerability to viral infection." In their 2021 paper in Environmental Pollution, Jie Han writes, "Respirable hazards such as micro(nano)plastics present in these may escalate from once an occupational hazard to a public health issue." 
It has been shown that fibers from textiles can accumulate in the lungs and cause pulmonary fibrosis with long-term effects like asthma and COPD [38 69]. Suffocating your lungs with tiny plastic and cotton particles sounds like a terrible idea during a pandemic that harms the lungs.
Hazardous Jet Streams
Masks have been shown to reduce the forward trajectory of breath in the studies where participants blew, talked, or coughed into a tube. As pointed out above, these studies ignore the leakage jets  generated out the edges of the mask, upward, to the sides, downward, and backward. These jet streams travel further than when not wearing a mask. If you cough while wearing your mask standing in line at the grocery store, it's true that the person directly in front of you will benefit from your mask use. The people behind and to the sides of you won't be so fortunate. They'll be bathed in the plume of your aerosol jet stream. Because the backward jet stream is the most pronounced, hair dressers are at particularly high risk as they're standing behind clients with masks on all day. The only masks that reduce the jet streams are properly fitted N95 type masks. Anything else is exacerbating the aerosol spread.
Many people, including health care workers , are suffering from “maskne” (mask acne), perioral dermatitis, “mask mouth,” increased dental caries, and sore throats from wearing a mask. That’s happening because bacteria are trapped and proliferating in the mask area [50 52 55] due to the humid, stagnant air, hampered ability to cleanse that area with normal respiration, and increased temperature around the mouth that we all can feel. It creates the perfect environment for bacterial growth on the face, in the mouth, and in the throat, and reduces the lungs ability to cleanse themselves. Hence sore throats, gingivitis, cavities, and acne. Since the face is connected to the mouth is connected to the throat is connected to the lungs, it’s not a stretch to consider that bacteria can accumulate in the lungs (along with those cotton fibers from your mask).
• A 2015 study  found that health care workers who wore cotton facemasks suffered from significantly more respiratory illness than those who wore surgical masks. The authors concluded, “Moisture retention, reuse of cloth masks and poor filtration may result in increased risk of infection.” More infection with masks... But aren't we wearing them to prevent infection?
• Previous research conducted by Dr Fauci himself  found that the main cause of death in the 1918 Spanish flu pandemic wasn’t from the flu, but actually from bacterial pneumonia. The public was forced to wear masks back then too. By breathing in the concentrated bacteria accumulating in our masks, we’re increasing the bacteria in our lungs and potentially sensitizing the immune system and increasing inflammation there. If covid lands in pre-inflamed lungs, that could increase the risk of the dreaded “cytokine storm” that causes most of the severe consequences. More bacteria in the lungs from the masks, at a time like this, is an exceptionally bad idea.
Our blood oxygen and carbon dioxide must stay within optimal ranges to keep us alert and healthy. Research has shown that masks do in fact lower oxygen availability and disrupt blood gases as a result.
OSHA has determined that an atmosphere is considered oxygen deficient if it is below 19.5% .
• Tests have shown that O2 concentration under the mask decreases to 17.6%  after only 60 seconds, a level considered unsafe by OSHA.
• Another study found that the oxygen availability under the masks was 13% lower than without the masks and the carbon dioxide (CO2) concentration was 30 times higher, even at rest .
• A study conducted in children  found that the inhaled level of carbon dioxide under the mask was six times higher than what was deemed safe by German authorities after only three minutes of use. The study was criticized and consequently retracted. Lead author Dr Harald Walach fully addressed each of the criticisms (link to his response is available on retractionwatch.com), but the retraction still stands. In his response, he stated that the burden of proof of safety is on those that wish to implement the intervention and called upon researchers to disprove his results in their own study. He also pointed out that the adverse effects of mask wearing reported by Kisielinski et al  are all symptoms of high carbon dioxide.
Breathing air with a lower O2 concentration reduces blood oxygen (resulting in hypoxemia) and increases blood carbon dioxide (resulting in hypercapnia). This has been well demonstrated in various populations [33 37 54 113]. The data demonstrating significant disruption to blood gasses caused by masks far outweighs the data showing no effect .
Altering blood gasses has significant downstream physiological consequences:
• A systematic review  that only included statistically significant data demonstrates consistent disruption in numerous measurements of blood gasses, heart rate, respiratory rate, all of which are "capable of causing pathological changes over long periods." Their analysis also revealed that mask wearing results in neurological impairments evidenced by significant exhaustion, disorientation, dizziness, confusion, decreased thinking ability, and lower psychomotoric ability.
• Numerous studies report increased headaches among masked health care workers [36 70 71 72 73 74].
• The journal Headache  reports that 81% of health care workers reported de novo headaches associated with wearing masks as a precaution during the covid19 era. Ninety-one percent of the health care workers that had existing headaches reported that the masks made their headaches worse and compromised their performance at work.
• Reduced oxygen suppresses the immune system [56 83] and fosters an acidic environment in the body . During a pandemic, suppressing the immune system of millions of essential workers and students will backfire.
• Many people certainly feel like they can’t breathe well with a mask, which increases stress, which we know to have negative health ramifications.
The downstream repercussions of the general public wearing masks for long periods are numerous, significant, and may result in long term chronic disease.
Masks reduce our oxygen levels, as we saw above. Hypoxia (low oxygen) suppresses the immune system [56 83]; reducing differentiation of CD4+ effector T cells (which kill pathogens) and increasing T Regulatory cells (which put the breaks on the immune response). Suppressing the immune system during a pandemic is a very bad idea.
There are psychological effects from wearing masks, especially regarding children. I’m not going to take time to delve into this because the physical harms combined with lack of efficacy are sufficient to reconsider the widespread mask mandates.
Exercising with a Mask
Because of the mandates to wear masks outside even when social distancing is possible, many people are exercising with masks on, including sports teams. Governments are completely ignoring the fact that the World Health Organization specifically recommends against wearing a mask  while exercising because “masks may reduce the ability to breathe comfortably. Sweat can make the mask become wet more quickly which makes it difficult to breathe and promotes the growth of microorganisms.” Again, microorganisms that we’ll be inhaling along with the nano particles.
• Researchers from the Medicine and Sports Unit in Spain report unhealthy disruptions in masked athletes blood gasses, "The use of masks in athletes causes hypoxic and hypercapnic breathing as evidenced by increased effort during exercise. The use of masks during a short exercise with an intensity around 6–8 METS, decreases O2 by 3.7% and increases the CO2 concentration by 20%." 
• Researchers from the Department of Exercise and Sports Sciences, Manipal College of Health Professions  warn, "Exercising with facemasks induces an acidic environment, and thus mobility of hypoxic natural killer cells to the target cells would be affected, aggravating the chances of infection during the pandemic."
• Researchers from Leipzig University  warn against wearing masks during exercise because, "Ventilation, cardiopulmonary exercise capacity and comfort are reduced by surgical masks and highly impaired by FFP2/N95 face masks in healthy individuals." They further concluded, “In addition, medical masks significantly impair the quality of life of their wearer. These effects have to be considered versus the potential protective effects of face masks on viral transmissions.”
• The Asia Pacific Journal of Sports Medicine  also found athletes suffer when working out with a mask on, "The laboratory study to investigate the physiological effect of wearing a facemask found that it significantly elevated heart rate and perceived exertion. Those participating in exercise need to be aware that facemasks increase the physiological burden of the body, especially in those with multiple underlying comorbidities."
• Research conducted on athletes at Baylor Scott & White Hospital in Dallas found that wearing a face mask while exercising has significant impacts during exercise . They report, "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." Any intervention that causes anxiety and shortness of breath should be urgently reconsidered, because the resulting increase in stress hormones is widely known to have numerous negative downstream effects.
• On the other hand, Shaw et al  found no difference in oxygen saturation and heart rate during several cycle challenges, with and without a mask. When there is conflicting research, the precautionary principle should be applied, considering 1) accumulating evidence of significant physiological impact, and 2) lack of high quality evidence of efficacy.
Dr Fauci and “anti maskers” were right when they said masks won’t help. There is abundant research that masks likely are not helping to prevent the spread of covid19. The new research supporting masks is weak and has major design flaws. Studies that demonstrate reduced particles out the front of the mask don’t account for the jet stream of redirected airflow, aerosols beyond the limit of detection, or the effect of moisture. Universal masking can be doing significant harm with regard to increased bacterial counts on the skin, in the mouth, throat, and potentially even lungs. This is of special concern to people wearing masks for long work shifts. It is also of concern for children whose disrupted oral microbiome may have long-term health consequences. We may not see the harms until it’s too late, and may not be able to meaningfully connect the dots.
It is reckless of our government to be mandating everyone wear a mask with such low quality evidence and the potential of significant harm. Our well-intentioned efforts to save lives sometimes do more harm than good. As citizens, we need to stay informed and not accept invalid, potentially harmful government mandates.
So What Can We Do?
For now, let’s stick with the measures that have been shown to help – social distancing, hand hygiene, avoiding chronic disease. Only don a fresh, clean, properly fitted N95 mask for short periods of time when we’re unavoidably close to others indoors.
About The Author
You may suspect that this summary is politically motivated. I can assure it is not. I’m a life-long liberal Democrat. I've devoted my life to health and wellness, and have advanced degrees and certifications in the health sciences. If I thought masks helped in any way, I would be all for them because I care deeply about people's wellbeing. I find it offensive how the science is being misrepresented, and how we are being manipulated and harmed in the process. I prefer not to provide my identity because I've found that people who want to propagate the myth that masks help go to great lengths attempting to discredit anyone who says otherwise, no matter how well qualified or how sound the research is. Personally, I can take the heat, but it's just a distraction. In reality, it doesn't matter who I am, because the research speaks for itself. Thank you for delving into this topic with me.
1 Xiao J, et al. Nonpharmaceutical Measures for Pandemic Influenza in Nonhealthcare Settings—Personal Protective and Environmental Measures. Emerg Infect Dis. 2020;26(5):967–975. https://dx.doi.org/10.3201/eid2605.190994
2 Ritter MA, et al. The operating room environment as affected by people and the surgical face mask. Clin Orthop Relat Res. 1975 Sep;(111):147–50. doi: 10.1097/00003086-197509000-00020. PMID: 1157412.
3 Laslett LJ, et al. Wearing of caps and masks not necessary during cardiac catheterization. Cathet Cardiovasc Diagn. 1989 Jul;17(3):158–60. doi: 10.1002/ccd.1810170306. PMID: 2766345
4 Tunevall TG. Postoperative wound infections and surgical face masks: a controlled study. World J Surg. 1991 May–Jun;15(3):383–7; discussion 387–8. doi: 10.1007/BF01658736. PMID: 1853618.
5 Lahme T, et al. Patientenmundschutz bei Regionalanästhesien. Hygienische Notwendigkeit oder entbehrliches Ritual? [Patient surgical masks during regional anesthesia. Hygenic necessity or dispensable ritual?]. Anaesthesist. 2001 Nov;50(11):846–51. German. doi: 10.1007/s00101-001-0229-x. PMID: 11760479.
6 Tunevall TG, et al. Influence of wearing masks on the density of airborne bacteria in the vicinity of the surgical wound. Eur J Surg. 1992 May;158(5):263–6. PMID: 1354489.
7 Bahli ZM. Does evidence based medicine support the effectiveness of surgical facemasks in preventing postoperative wound infections in elective surgery? J Ayub Med Coll Abbottabad. 2009 Apr–Jun;21(2):166–70. PMID: 20524498.
8 Ha'eri GB, et al. The efficacy of standard surgical face masks: an investigation using "tracer particles". Clinical Orthopaedics and Related Research. 1980 May(148):160–162. PMID: 7379387.
9 Skinner, et al. (2001). Do Anaesthetists Need to Wear Surgical Masks in the Operating Theatre? A Literature Review with Evidence-Based Recommendations. Anaesthesia and intensive care. doi: 10.1177/0310057X0102900402. PMID: 11512642.
10 Ha'eri GB, et al. The efficacy of standard surgical face masks: an investigation using "tracer particles". Clinical Orthopaedics and Related Research. 1980 May(148):160–162. PMID: 7379387.
11 Ritter MA, et al. The operating room environment as affected by people and the surgical face mask. Clin Orthop Relat Res. 1975 Sep;(111):147–50. doi: 10.1097/00003086-197509000-00020. PMID: 1157412.
12 Skinner MW, et al. Do anaesthetists need to wear surgical masks in the operating theatre? A literature review with evidence-based recommendations. Anaesth Intensive Care. 2001 Aug;29(4):331–8. doi: 10.1177/0310057X0102900402. PMID: 11512642.
13 Wang MX, et al. Effectiveness of Surgical Face Masks in Reducing Acute Respiratory Infections in Non-Healthcare Settings: A Systematic Review and Meta-Analysis. Front Med (Lausanne). 2020;7:564280. Published 2020 Sep 25. doi:10.3389/fmed.2020.564280
15 Kiran Bhaganagar, et al. Local atmospheric factors that enhance air-borne dispersion of coronavirus — High-fidelity numerical simulation of COVID19 case study in real-time. Environmental Research. 2020 December; (191). doi: 10.1016/j.envres.2020.110170
17 Chu, DK et al. Physical distancing, face masks, and eye protection to prevent person-to-person transmission of SARS-CoV-2 and COVID-19: a systematic review and meta-analysis. Lancet 2020; 395: 1973–87. doi: 0.1016/ S0140-6736(20)31142-9
18 Asadi S, et al. Efficacy of masks and face coverings in controlling outward aerosol particle emission from expiratory activities. Sci Rep 10, 15665 (2020). https://doi.org/10.1038/s41598-020-72798-7
19 Fuk-Woo Chan J, et al. Surgical Mask Partition Reduces the Risk of Noncontact Transmission in a Golden Syrian Hamster Model for Coronavirus Disease 2019 (COVID-19), Clinical Infectious Diseases. doi:10.1093/cid/ciaa644
21 MacIntyre CR, et al. A cluster randomised trial of cloth masks compared with medical masks in healthcare workers. BMJ Open 2015;5:e006577. doi:10.1136/bmjopen-2014-006577
22 Morens DM, et al. Predominant role of bacterial pneumonia as a cause of death in pandemic influenza: Implications for pandemic influenza preparedness. The Journal of Infectious Diseases doi: 10.1086/591708 (2008).
23 Samannan R, et al. Effect of Face Masks on Gas Exchange in Healthy Persons and Patients with COPD. Preprint at https://www.atsjournals.org/doi/pdf/10.1513/AnnalsATS.202007-812RL
25 Fischer EP, et al. Low-cost measurement of face mask efficacy for filtering expelled droplets during speech. Science Advances. doi: 10.1126/sciadv.abd3083
27 Van Dyke ME, et al. Trends in County-Level COVID-19 Incidence in Counties With and Without a Mask Mandate — Kansas, June 1–August 23, 2020. MMWR Morb Mortal Wkly Rep 2020;69:1777–1781. doi: http://dx.doi.org/10.15585/mmwr.mm6947e2
28 Desai AN, et al. Medical Masks. JAMA. 2020;323(15):1517–1518. doi:10.1001/jama.2020.2331
29 Pan J, et al. Inward and outward effectiveness of cloth masks, a surgical mask, and a face shield. Civil and Environmental Engineering, Virginia Tech, Blacksburg, VA 240614. Preprint: https://www.medrxiv.org/content/10.1101/2020.11.18.20233353v1.full.pdf
30 Bundgaard H, et al. Effectiveness of Adding a Mask Recommendation to Other Public Health Measures to Prevent SARS-CoV-2 Infection in Danish Mask Wearers. 18 November 2020. Annals of Internal Medicine. https://doi.org/10.7326/M20-6817
31 Klompas M, et al. Universal Masking in Hospitals in the Covid-19 Era. May 2020 N Engl J Med 2020; 382:e63 doi: 10.1056/NEJMp2006372
32 Leffler CT, et al. (2020). Association of Country-wide Coronavirus Mortality with Demographics, Testing, Lockdowns, and Public Wearing of Masks, The American Journal of Tropical Medicine and Hygiene, 103(6), 2400–2411. doi: https://doi.org/10.4269/ajtmh.20-1015
33 Beder A, et al. Preliminary report on surgical mask induced deoxygenation during major surgery. Neurocirugia (Astur). 2008 Apr;19(2):121–6. doi: 10.1016/s1130-1473(08)70235-5. PMID: 18500410.
34 Lazzarino A, et al. Face masks for the public during the covid-19 crisis. BMJ 2020;369:m1435
35 Withdrawn Adjodah D, et al. Decrease in Hospitalizations for COVID-19 after Mask Mandates in 1083 U.S. Counties
36 Lim EC, et al. Headaches and the N95 face-mask amongst healthcare providers. Acta Neurol Scand. 2006;113(3):199–202. doi:10.1111/j.1600-0404.2005.00560.x
37 Kao TW, et al. The physiological impact of wearing an N95 mask during hemodialysis as a precaution against SARS in patients with end-stage renal disease. J Formos Med Assoc. 2004 Aug;103(8):624–8. PMID: 15340662.
38 Ghio A, et al. Pulmonary Fibrosis and Ferruginous Bodies Associated with Exposure to Synthetic Fibers. 2006 Oct 1. https://doi.org/10.1080/01926230600932448
39 IHME COVID-19 Forecasting Team., Reiner, R.C., Barber, R.M. et al. Modeling COVID-19 scenarios for the United States. Nat Med (2020). https://doi.org/10.1038/s41591-020-1132-9
40 Phillip W Magness. The Case for Mask Mandate Rests on Bad Data. Wall Street Journal. 2020 Nov.
41 Ontario Nurses’ Association. ONA Wins Second Decision on “Unreasonable and Illogical” Vaccinate or Mask Influenza Policies. Newswire.ca 2018 Sept.
42 Bulfone TC, et al. Outdoor Transmission of SARS-CoV-2 and Other Respiratory Viruses: A Systematic Review. J Infect Dis. 2021 Feb 24;223(4):550–561. doi: 10.1093/infdis/jiaa742. PMID: 33249484; PMCID: PMC7798940.
43 Lyu W, et al. Community Use Of Face Masks And COVID-19: Evidence From A Natural Experiment Of State Mandates In The US. Health Aff (Millwood). 2020 Aug;39(8):1419–1425. doi: 10.1377/hlthaff.2020.00818. Epub 2020 Jun 16.
44 Viola I, et al. Face Coverings, Aerosol Dispersion and Mitigation of Virus Transmission Risk. Engineering in Medicine and Biology. 2021. doi: 10.1109/OJEMB.2021.3053215
45 Yeung W, et al. Assessment of Proficiency of N95 Mask Donning Among the General Public in Singapore. JAMA Netw Open. 2020;3(5):e209670. doi:10.1001/jamanetworkopen.2020.9670
46 Jefferson, T et al. Physical interventions to interrupt or reduce the spread of respiratory viruses. Part 1 — Face masks, eye protection and person distancing: systematic review and meta-analysis. MedRxiv April 2020. doi: https://doi.org/10.1101/2020.03.30.20047217
47 Brainard J, et al. Facemasks and similar barriers to prevent respiratory illness such as COVID-19: A rapid systematic review. MedRxiv April 2020. doi: https://doi.org/10.1101/2020.04.01.20049528
48 Brooks JT, et al. Maximizing Fit for Cloth and Medical Procedure Masks to Improve Performance and Reduce SARS-CoV-2 Transmission and Exposure, 2021. MMWR Morb Mortal Wkly Rep. ePub: 10 February 2021. doi: http://dx.doi.org/10.15585/mmwr.mm7007e1
49 Chandrasekaran B, et al. "Exercise with facemask; Are we handling a devil's sword?" — A physiological hypothesis. Med Hypotheses. 2020;144:110002. doi:10.1016/j.mehy.2020.110002
50 Blachere FM, et al. Assessment of influenza virus exposure and recovery from contaminated surgical masks and N95 respirators. J Virol Methods. 2018 Oct;260:98–106. doi: 10.1016/j.jviromet.2018.05.009. Epub 2018 Jul 17. PMID: 30029810; PMCID: PMC6482848.
51 Bischoff WE, et al. Exposure to influenza virus aerosols during routine patient care. J Infect Dis. 2013 Apr;207(7):1037–46. doi: 10.1093/infdis/jis773. Epub 2013 Jan 30. PMID: 23372182.
52 Zhiqing L, et al. Surgical masks as source of bacterial contamination during operative procedures. J Orthop Translat. 2018 Jun 27;14:57–62. doi: 10.1016/j.jot.2018.06.002. PMID: 30035033; PMCID: PMC6037910.
53 Jacobson TA, et al. Direct human health risks of increased atmospheric carbon dioxide. Nat Sustain 2, 691–701 (2019). https://doi.org/10.1038/s41893-019-0323-1
54 Smith CL, et al. Carbon dioxide rebreathing in respiratory protective devices: influence of speech and work rate in full-face masks. Ergonomics. 2013;56(5):781–90. doi: 10.1080/00140139.2013.777128. PMID: 23514282.
55 Chughtai AA, et al. Contamination by respiratory viruses on outer surface of medical masks used by hospital healthcare workers. BMC Infect Dis. 2019 Jun 3;19(1):491. doi: 10.1186/s12879-019-4109-x. PMID: 31159777; PMCID: PMC6547584.
56 Lukashev D, et al. Cutting Edge: Hypoxia-Inducible Factor 1α and Its Activation-Inducible Short Isoform I.1 Negatively Regulate Functions of CD4+ and CD8+ T Lymphocytes The Journal of Immunology October 15, 2006, 177 (8) 4962–4965; doi: 10.4049/jimmunol.177.8.4962
57 Kellogg, WH. An Experimental Study of the Efficacy of Gauze Face Masks. California State Board of Health. https://ajph.aphapublications.org/doi/pdf/10.2105/AJPH.10.1.34
58 Dr. SHIVA LIVE: Masks & Oral Health: Systems Biology of Periodontal Disease & Effect of Masks
59 Borovoy B, et al. Friable Mask Particulate and Lung Vulnerability. Primary Doctor Medical Journal September 2020. https://pdmj.org/papers/masks_false_safety_and_real_dangers_part1/
60 Borovoy B, et al. Microbial Challenges from Masks. Primary Doctor Medical Journal October 2020. https://pdmj.org/papers/masks_false_safety_and_real_dangers_part2/
61 Borovoy B, et al. Hypoxia, Hypercapnia, and Physiological Effects. Primary Doctor Medical Journal November 2020. https://pdmj.org/papers/masks_false_safety_and_real_dangers_part3/
62 Borovoy B, et al. Proposed Mechanisms by which Masks Increase Risk of COVID-19. Primary Doctor Medical Journal December 2020. https://pdmj.org/papers/masks_false_safety_and_real_dangers_part4/
63 Editorial Committee of the American Public Health Association. A working program against influenza prepared by an editorial committee of the American Public Health Association. 1919. Am J Public Health. 2010;100(11):2070–2072. doi:10.2105/ajph.100.11.2070
64 Joule A. Retract The Lancet’s (and WHO funded) published study on mask wearing — Criticism of “Physical distancing, face masks, and eye protection to prevent person-to-person transmission of SARS-CoV-2 and Covid-19: a systematic review and meta-analyses”. EconomicsFAQ.
65 Meta Research Innovation Center at Stanford. FORMAL REQUEST FOR THE RETRACTION OF ZHANG ET AL., 2020
66 OSHA (Occupation Safety & Health Administration). Confined or Enclosed Spaces and Other Dangerous Atmospheres » Oxygen-Deficient or Oxygen-Enriched Atmospheres.
67 Holmer I, et al. Minute Volumes and Inspiratory Flow Rates During Exhaustive Treadmill Walking Using Respirators. The Annals of Occupational Hygiene, Volume 51, Issue 3, April 2007. https://doi.org/10.1093/annhyg/mem004
68 RETRACTED: Vainshelboim B. “Facemasks in the COVID-19 era: A health hypothesis”. Medical Hypotheses. 2021;146:110411. doi:10.1016/j.mehy.2020.110411
69 Lai PS, et al. Long-term respiratory health effects in textile workers. Curr Opin Pulm Med. 2013;19(2):152–157. doi:10.1097/MCP.0b013e32835cee9a
70 Ong J, et al. Headaches Associated With Personal Protective Equipment — A Cross-Sectional Study Among Frontline Healthcare Workers During COVID-19. Headache. 2020 May;60(5):864–877. doi: 10.1111/head.13811.
71 Rosner E (2020) Adverse Effects of Prolonged Mask Use among Healthcare Professionals during COVID-19. J Infect Dis Epidemiol 6:130.
72 Galanis P, et al. Impact of personal protective equipment use on health care workers’ physical health during the COVID-19 pandemic: a systematic review and meta-analysis. February 2021. medRxiv preprint doi: https://doi.org/10.1101/2021.02.03.21251056
73 Purushothaman PK, et al. Effects of Prolonged Use of Facemask on Healthcare Workers in Tertiary Care Hospital During COVID-19 Pandemic. Indian J Otolaryngol Head Neck Surg 73, 59–65 (2021). https://doi.org/10.1007/s12070-020-02124-0
74 Rapisarda L, et al. Facemask headache: a new nosographic entity among healthcare providers in COVID-19 era. Neurol Sci (2021). https://doi.org/10.1007/s10072-021-05075-8
75 Hajjij A, et al. “Personal Protective Equipment and Headaches: Cross-Sectional Study Among Moroccan Healthcare Workers During COVID-19 Pandemic”. Cureus. 2020 Dec;12(12):e12047. doi: 10.7759/cureus.12047.
76 Çağlar A, et al. “Symptoms associated with personal protective equipment among frontline healthcare professionals during the COVID-19 pandemic”. Disaster Medicine and Public Health Preparedness, 1–15. doi:10.1017/dmp.2020.455
77 Ramirez-Moreno JM, et al. “Mask-associated ‘de novo’ headache in healthcare workers during the COVID-19 pandemic”. Occupational and Environmental Medicine. doi: 10.1136/oemed-2020-106956.
78 Rumeesha Z, et al. “Association of Personal Protective Equipment with De Novo Headaches In Frontline Healthcare Workers during COVID-19 Pandemic: A Cross-Sectional Study”. European Journal of Dentistry. 2020 Dec;14(S 01):S79–S85. doi: 10.1055/s-0040-1721904.
79 Singh M, et al. “Personal protective equipment induced facial dermatoses in healthcare workers managing Coronavirus disease 2019”. Journal of the European Academy of Dermatology and Venereology, 34: e378–e380. https://doi.org/10.1111/jdv.16628
80 Edward DGF. Resistance of influenza virus to drying and its demonstration on dust. Lancet 2, 664–666 (1941).
81 Watanabe T, et al. Development of a dose-response model for SARS coronavirus. Risk Anal. 2010;30(7):1129–1138. doi:10.1111/j.1539-6924.2010.01427.x
82 Jefferson T, et al. Physical interventions to interrupt or reduce the spread of respiratory viruses. Cochrane Database of Systematic Reviews 2020, Issue 11. Art. No.: CD006207. DOI: 10.1002/14651858.CD006207.pub5. https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD006207.pub5/full
83 Westendorf A, et al. Hypoxia Enhances Immunosuppression by Inhibiting CD4+ Effector T Cell Function and Promoting Treg Activity. Cell Physiol Biochem 2017;41:1271–1284. doi: 10.1159/000464429
84 Han J, et al. Need for assessing the inhalation of micro(nano)plastic debris shed from masks, respirators, and home-made face coverings during the COVID-19 pandemic. Environ Pollut. 2021;268(Pt B):115728. doi:10.1016/j.envpol.2020.115728
85 Joo H, et al. Decline in COVID-19 Hospitalization Growth Rates Associated with Statewide Mask Mandates — 10 States, March–October 2020. MMWR Morb Mortal Wkly Rep 2021;70:212–216. DOI: http://dx.doi.org/10.15585/mmwr.mm7006e2external icon
86 Alexander P, et al. The CDC’s Mask Mandate Study: Debunked. American Institute for Economic Research. March 2021. https://www.aier.org/article/the-cdcs-mask-mandate-study-debunked/
87 Howard J, et al. An evidence review of face masks against COVID-19. Proceedings of the National Academy of Sciences. January 2021. https://doi.org/10.1073/pnas.2014564118
88 Does the use of face masks in the general population make a difference to spread of infection? The University of Edinburgh, Usher Institute; Usher Network for Covid19 Evidence Reviews. May 2020. https://www.ed.ac.uk/usher/uncover
89 Fisher K, et al. Community and Close Contact Exposures Associated with COVID-19 Among Symptomatic Adults ≥18 Years in 11 Outpatient Health Care Facilities. Morbidity and Mortality Weekly Report 1258. September 2020.
90 Vanden Driessche K, et al. The Cough Cylinder: a tool to study measures against airborne spread of (myco-) bacteria. The International Journal of Tuberculosis and Lung Disease. January 2013. doi: https://doi.org/10.5588/ijtld.12.0289
91 Wood ME, et al. Face Masks and Cough Etiquette Reduce the Cough Aerosol Concentration of Pseudomonas aeruginosa in People with Cystic Fibrosis. Am J Respir Crit Care Med. 2018 Feb 1;197(3):348–355. doi: 10.1164/rccm.201707-1457OC. PMID: 28930641.
92 Stockwell RE, et al., Face masks reduce the release of Pseudomonas aeruginosa cough aerosols when worn for clinically relevant periods. Am. J. Respir. Crit. Care Med. 198, 1339–1342 (2018). https://doi.org/10.1164/rccm.201805-0823LE PubMed: 30028634
93 Dharmadhikari AS, et al. Surgical face masks worn by patients with multidrug-resistant tuberculosis: Impact on infectivity of air on a hospital ward. Am. J. Respir. Crit. Care Med. 185, 1104–1109 (2012). doi: 10.1164/rccm.201107-1190OC. PMID: 22323300.
94 Greene, VW, et al. Method for Evaluating Effectiveness of Surgical Masks. Journal of Bacteriology Mar 1962. PMID: 13901536.
95 Quesnel L. The efficiency of surgical masks of varying design and composition. Br J Surg. 1975. (and not only that but found much lower filtration of smaller particles – as in aerosolized viruses). doi: 10.1002/bjs.1800621203. PMID: 1203649.
96 Davies A, et al. Testing the efficacy of homemade masks: would they protect in an influenza pandemic? Disaster Med Public Health Prep. 2013 Aug;7(4):413–8. doi: 10.1017/dmp.2013.43. PMID: 24229526.
97 Milton DK, et al. Influenza virus aerosols in human exhaled breath: particle size, culturability, and effect of surgical masks. PLoS Pathog. 2013 Mar;9(3):e1003205. doi: 10.1371/journal.ppat.1003205. Epub 2013 Mar 7. PMID: 23505369.
98 Leung NHL, et al. Respiratory virus shedding in exhaled breath and efficacy of face masks. Nat Med. 2020 May;26(5):676–680. doi: 10.1038/s41591-020-0843-2. Epub 2020 Apr 3. Erratum in: Nat Med. 2020 May 27;: PMID: 32371934.
99 Johnson DF, et al. A Quantitative Assessment of the Efficacy of Surgical and N95 Masks to Filter Influenza Virus in Patients with Acute Influenza Infection, Clinical Infectious Diseases, Volume 49, Issue 2, 15 July 2009, Pages 275–277, https://doi.org/10.1086/600041
100 Verma S, et al. Visualizing the effectiveness of face masks in obstructing respiratory jets. Physics of Fluids 32, 061708 (2020); https://doi.org/10.1063/5.0016018
101 Dato VM, et al. Simple respiratory mask. Emerg Infect Dis. 2006;12(6):1033–1034. doi:10.3201/eid1206.051468
102 Runde D, et al. The “double eights mask brace” improves the fit and protection of a basic surgical mask amidst COVID‐19 pandemic. Journal of the American College of Emergency Physicians. December 2020 https://doi.org/10.1002/emp2.12335
103 Wu LT. A Treatise on Pneumonic Plague (League of Nations, Health Organization, 1926), pp. 373–398.
104 Chughtai AA, et al. Contamination by respiratory viruses on outer surface of medical masks used by hospital healthcare workers. BMC Infect Dis. 2019 Jun 3;19(1):491. doi: 10.1186/s12879-019-4109-x. PMID: 31159777; PMCID: PMC6547584.
105 Martin GP, et al. Face masks for the public during Covid:19: an appeal for caution in policy. https://osf.io/preprints/socarxiv/uyzxe/
106 Gandhi M, et al. The Time for Universal Masking of the Public for Coronavirus Disease 2019 Is Now, Open Forum Infectious Diseases, Volume 7, Issue 4, April 2020, ofaa131, https://doi.org/10.1093/ofid/ofaa131
107 Sim SW, et al. The use of facemasks to prevent respiratory infection: a literature review in the context of the Health Belief Model. Singapore Med J. 2014 Mar;55(3):160–7. doi: 10.11622/smedj.2014037. PMID: 24664384; PMCID: PMC4293989.
108 Fikenzer S, et al. Effects of surgical and FFP2/N95 face masks on cardiopulmonary exercise capacity. Clin Res Cardiol 109, 1522–1530 (2020). https://doi.org/10.1007/s00392-020-01704-y
109 Ying-Ying A, et al. Impact of the COVID-19 pandemic on sports and exercise. Asia Pacific Journal of Sports Medicine. October 2020. https://doi.org/10.1016/j.asmart.2020.07.006
110 Shaw K, et al. Wearing of Cloth or Disposable Surgical Face Masks has no Effect on Vigorous Exercise Performance in Healthy Individuals. Int J Environ Res Public Health. 2020;17(21):8110. Published 2020 Nov 3. doi:10.3390/ijerph17218110
111 Driver S, et al. Effects of wearing a cloth face mask on performance, physiological and perceptual responses during a graded treadmill running exercise test. British Journal of Sports Medicine Published Online First: 13 April 2021. doi: 10.1136/bjsports-2020-103758
112 Liu, C, et al. Effects of Wearing Masks on Human Health and Comfort during the COVID-19 Pandemic. IOP Conf. Ser. Earth Environ. Sci. 2020, 531, 012034.
113 Kisielinski K, et al. Is a Mask That Covers the Mouth and Nose Free from Undesirable Side Effects in Everyday Use and Free of Potential Hazards? Int. J. Environ. Res. Public Health 2021, 18(8), 4344; https://doi.org/10.3390/ijerph18084344
114 Fernando P, et al. COVID-19 and mask in sports, Apunts Sports Medicine, Volume 55, Issue 208, 2020, Pages 143–145, ISSN 2666–5069, https://doi.org/10.1016/j.apunsm.2020.06.002
115 Drewnick F, et al. Aerosol filtration efficiency of household materials for homemade face masks: Influence of material properties, particle size, particle electrical charge, face velocity, and leaks, Aerosol Science and Technology, 55:1, 63–79, doi: 10.1080/02786826.2020.1817846
116 Süt, N. “Study designs in medicine.” Balkan medical journal vol. 31,4 (2014): 273–7. doi:10.5152/balkanmedj.2014.1408
117 Zhang R, et al. Identifying airborne transmission as the dominant route for the spread of COVID-19. Proceedings of the National Academy of Sciences Jun 2020, 202009637; doi:10.1073/pnas.2009637117
118 Vaughan W. The American Journal of Hygiene. Influenza, An Epidemiologic Study. July 1921. http://www.vaughan.org/bios/wtv/WTVinfluenza.pdf
119 Guerra D, et al. Mask mandate and use efficacy in state-level COVID-19 containment. Preprint available on https://www.medrxiv.org/content/10.1101/2021.05.18.21257385v1.full.pdf
120 Qian H, et al. Indoor transmission of SARS-CoV-2. International Journal of Indoor Environment and Health. 31 October 2020 https://doi.org/10.1111/ina.12766
121 McGreevy R. Outdoor transmission accounts for 0.1% of State’s Covid-19 cases. The Irish Times. April 5, 2021.
122 Weed M, et al. Rapid Scoping Review of Evidence of Outdoor Transmission of COVID-19. The Centre for Sport, Physical Education & Activity Research. September 2020. https://www.canterbury.ac.uk/science-engineering-and-social-sciences/spear/docs/REPORT-Outdoor-Transmission-of-COVID-19.pdf
123 Epperly DE, et al. COVID-19 Aerosolized Viral Loads, Environment, Ventilation, Masks, Exposure Time, Severity, And Immune Response: A Pragmatic Guide Of Estimates medRxiv 2020.10.03.20206110; https://doi.org/10.1101/2020.10.03.20206110
124 Belosi F, et al. On the concentration of SARS-CoV-2 in outdoor air and the interaction with pre-existing atmospheric particles. Environ Res. 2021;193:110603. doi:10.1016/j.envres.2020.110603
125 RETRACTED: Mehra MR, et al. Hydroxychloroquine or chloroquine with or without a macrolide for treatment of COVID-19: a multinational registry analysis Published: May 22, 2020 doi: https://doi.org/10.1016/S0140-6736(20)31180-6
126 Andersen KG, et al. The proximal origin of SARS-CoV-2. Nat Med 26, 450–452 (2020). https://doi.org/10.1038/s41591-020-0820-9
127 Bryant A, Lawrie TA, et al. Ivermectin for Prevention and Treatment of COVID-19 Infection: A Systematic Review, Meta-analysis, and Trial Sequential Analysis to Inform Clinical Guidelines. Am J Ther. 2021 Jun 21;28(4):e434-e460. doi: 10.1097/MJT.0000000000001402. PMID: 34145166; PMCID: PMC8248252.
128 RETRACTED: Walach H, et al. Experimental Assessment of Carbon Dioxide Content in Inhaled Air With or Without Face Masks in Healthy Children: A Randomized Clinical Trial. JAMA Pediatr. 2021 Jun 30. doi: 10.1001/jamapediatrics.2021.2659. Epub ahead of print. PMID: 34190984.
129 Schauer SG, et al. Analysis of the Effects of COVID-19 Mask Mandates on Hospital Resource Consumption and Mortality at the County Level. South Med J. 2021;114(9):597-602. doi:10.14423/SMJ.0000000000001294