Pardon me, maybe I should have said Bitchute instead of You Tube.
As far as the mask smoke test, do you mean this guy?
Doctor with expired license falsely claims masks don’t work
No, a vaping demo doesn’t prove that masks don’t work against COVID-19
There's nothing wrong with checking out differing viewpoints, but some logic must be applied to determine factualness. Usually searching for the publication and/or the author or scientist making the claim is sufficient (for me).
If anything can leak through or out around a mask, something can leak in. Will it be enough to cause an infection? Can it successfully negotiate sudden changes in direction of airflow (the principle by which particle separators that protect helicopter engines work)? Maybe. Maybe not. That video may not prove that masks are useless to the satisfaction of some, but it still demonstrates mask protection imperfection.
And are "droplets" the only concern with masks? My earliest research suggested that they were the most likely cause of aerial transmission, but, from having read many claims of airborne transmission, I went looking for more information:
Dismantling myths on the airborne transmission of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) January 12, 2021
"There is little, if any, direct evidence for the transmission of SARS-CoV-2 via any specific pathway. This statement applies to fomites and direct contact just as much as for large droplets and smaller airborne particles. It is notable that transmission through large droplets has never been demonstrated directly for any respiratory virus infection [7], [17]. The proof required to elicit these routes of transmission should include genomic sequencing and matching of the target pathogen at source (e.g. on fomites or hands) with that causing subsequent disease in the recipient, along with sufficient evidence to exclude any other source of the pathogen strain before or during the study. However, genomic studies tracking a single virus are very difficult and expensive to perform, and they may fail [18]."
Not all masks are the same, obviously. Not all masks are worn properly, obviously. I see many people with commercially-made cloth and disposable masks who do not bother to use the bendy strips that improve the “seal” around the wearers’ noses.
I have quality, dual-layer masks that can accept filters. The earlier masks that my sister and I made are dual-layer with two types of fabric and can accept filters. We used 3M MERV-13 furnace filter material for those. Other than a six-hour trial of our home-made masks to test the difference in comfort, acceptability of reduction to breathing, and leakage around the bridge of my nose, I have not used filters. I clamp the nose-bridge-stiffener-thingy down as firmly as I can, partially because I do not like air being blown into my eyeballs and/or fogging my glasses when worn.
Are masks better than nothing? Maybe. Should people wear them? Why not?
I’ve pasted some relevant quotes from
An evidence review of face masks against COVID-19 PNAS January 26, 2021, one of the references in one of the two fact-checking links that you provided, below.
“Therefore, we should not be surprised to find that there is
no RCT (Randomized Controlled Trial)
for the impact of masks on community transmission of any respiratory infection in a pandemic.”
“
Only one observational study has directly analyzed the impact of mask use in the community on COVID-19 transmission. The study looked at the reduction of secondary transmission of SARS-CoV-2 in Beijing households by face mask use (10). It found that face masks were 79% effective in preventing transmission, if they were used by all household members prior to symptoms occurring.
The study did not look at the relative risk of different types of mask.”
“They found that ‘face mask use
could result in a large reduction in risk of infection.’ However, the review included only three studies of mask use outside health care settings, all of which were of SARS, not of SARS-CoV-2, one of which was incorrectly categorized (it occurred in a hospital, but during family and friend visits), and one of which found that none of the households wearing masks had any infections, but was too underpowered to draw any conclusions (12). The remaining study found the use of masks was strongly protective, with a risk reduction of 70% for those that always wore a mask when going out (13), but
it did not look at the impact of masks on transmission from the wearer. It is not known to what degree analysis of other coronaviruses can be applied to SARS-CoV-2. None of the studies looked at the relative risks of different types of mask.”
“Overall, evidence from RCTs and observational studies is
informative, but not compelling on its own.”
“
None of the studies looked specifically at cloth masks.”
“A Cochrane review (15) on physical interventions to interrupt or reduce the spread of respiratory viruses included 67 RCTs and observational studies. It found that ‘overall masks were the best performing intervention across populations, settings and threats.’ There is a similar preprint review by the same lead author (16), in which only studies where
mask wearing was tested as a stand-alone intervention were included, without combining it with hand hygiene and physical distancing, and excluding observational studies. That review concluded that ‘there was insufficient evidence to provide a recommendation on the use of facial barriers without other measures.’ MacIntyre and Chughtai (17) published a review evaluating masks as protective intervention for the community, protection for health workers, and as source control. The authors conclude that ‘community mask use by well people
could be beneficial, particularly for COVID-19, where transmission may be pre-symptomatic. The studies of masks as source control also
suggest a benefit, and may be important during the COVID-19 pandemic in universal community face mask use as well as in health care settings.’”
“The Usher Institute incorporated laboratory as well as epidemiological evidence in their review (18), finding that ‘homemade masks worn by sick people
can reduce virus transmission by mitigating aerosol dispersal. Homemade masks worn by sick people
can also reduce transmission through droplets.’ One preprint systematic review (19) including epidemiological, theoretical, experimental, and clinical evidence found that ‘face masks in a general population
offered significant benefit in preventing the spread of respiratory viruses especially in the pandemic situation,
but its utility is limited by inconsistent adherence to mask usage.’ On the other hand, a preprint systematic review that only included RCTs and observational studies (20) concluded, based on the RCTs, that
there was only weak evidence for a small effect from mask use in the community, but that the RCTs often suffered from poor compliance and controls. It found that, in observational studies, the evidence in favor of wearing face masks was stronger.”
“A randomized intervention trial (24) found that ‘face masks and hand hygiene combined
may reduce the rate of ILI [influenza-like illness] and confirmed influenza in community settings.’”
“Overall, direct evidence of the efficacy of mask use is
supportive, but inconclusive. Since there are no RCTs, only one observational trial, and unclear evidence from other respiratory illnesses,
we will need to look at a wider body of evidence.”
