4 ms·

> We simply don't know if n95 masks provide any protection -- personal or otherwise -- in the real world. That is simply not true. First, doctors and research

by azakai 4y ago

> We simply don't know if n95 masks provide any protection -- personal or otherwise -- in the real world. That is simply not true. First, doctors and researchers consistently say that N95s are known to provide protection against Covid. Second, this is the first google result on that topic: https://www.cdc.gov/mmwr/volumes/71/wr/mm7106e1.htm https://www.cdc.gov/mmwr/volumes/71/wr/mm7106e1.htm Quoting from that CDC page: > What is already known about this topic? > Face masks or respirators (N95/KN95s) effectively filter virus-sized particles in laboratory settings. The real-world effectiveness of face coverings to prevent acquisition of SARS-CoV-2 infection has not been widely studied. > What is added by this report? > Consistent use of a face mask or respirator in indoor public settings was associated with lower odds of a positive SARS-CoV-2 test result (adjusted odds ratio = 0.44). Use of respirators with higher filtration capacity was associated with the most protection, compared with no mask use. > What are the implications for public health practice? > In addition to being up to date with recommended COVID-19 vaccinations, consistently wearing a comfortable, well-fitting face mask or respirator in indoor public settings protects against acquisition of SARS-CoV-2 infection; a respirator offers the best protection. You can say that that might be just correlation, but as those quotes mention, we do know how N95s work: they filter viral particles. That is easy to prove in lab settings. Real-world settings involve more factors, like how well-fitting the mask is, but it would be very surprising if a good N95 properly used did not offer any protection! N95 masks work. It's a good idea to wear one when relevant.

timr 4y ago
> That is simply not true. > First, doctors and researchers consistently say that N95s are known to provide protection against Covid. I just provided you with the sum total of medical evidence supporting the claim. Citing unspecified "doctors and researchers" is not a rebuttal. You are repeating hearsay, which was exactly my point. Also, you should know that that MMWR study you've chosen to emphasize here was widely panned by scientists on both sides of the mask debate. It's based on a telephone survey with a 13% response rate. The statistics are hopelessly biased due to the test-seeking behavior of the study participants. It is not credible: https://vinayprasadmdmph.substack.com/p/mask-studies-reach-a-new-scientific https://vinayprasadmdmph.substack.com/p/mask-studies-reach-a... It's good that you pointed it out, however, because it's a perfect illustration of the abysmal level of "evidence" that has been used to support similar claims throughout the pandemic. Unfortunately, a many terrible "papers" were published and widely distributed on masks, including many in "good" journals. If you don't understand how to appraise medical evidence, you will be easily misled. > N95 masks work. It's a good idea to wear one when relevant. Unfortunately, there is no good evidence supporting this assertion, and "when relevant" is essentially unknown.
- azakai 4y ago
  It's not unspecified "doctors and researchers". It's the overwheming consensus among medical professionals. The CDC recommends masks, as I linked. So does the WHO, https://www.who.int/news-room/questions-and-answers/item/coronavirus-disease-covid-19-masks https://www.who.int/news-room/questions-and-answers/item/cor... And so does the European CDC, https://www.ecdc.europa.eu/en/publications-data/using-face-masks-community-reducing-covid-19-transmission https://www.ecdc.europa.eu/en/publications-data/using-face-m... etc. etc. The picture is very clear here. And, again, the lab evidence is incredibly supportive. We know that N95s filter viral particles. It's possible in theory that that doesn't end up mattering - say if people never wear them right, or if they end up taking more risks because they think they are safer - but that seems unlikely when other evidence says otherwise, and the experts concur.
  - ehvatum 4y ago
    > The picture is very clear here. I wish it were. It should not be difficult to verify that N95 masks filter COVID virus particles effectively. If such a study had been performed, nobody could reasonably hypothesize that, owing to the properties of the viral envelope, an N95 filter could stop nanometer black carbon particles but not COVID viruses of the same size. It is baffling that the very basic experiment has not been done: DOES N95 FILTER COVID? The advancement of human knowledge absolutely depends on VERIFYING assumptions. Institutionalizing common beliefs without empirical data is a crime against science.
    - azakai 4y ago
      Why are you certain such studies have not been done? Plenty of things have been published in that space. For example, https://academic.oup.com/jid/article/226/2/199/6582941 https://academic.oup.com/jid/article/226/2/199/6582941 https://www.frontiersin.org/articles/10.3389/fmed.2021.654317/full https://www.frontiersin.org/articles/10.3389/fmed.2021.65431... You might respond with some specific skepticism about some particular detail in either study. But e.g. the first is in the respected Journal of Infectious Diseases. It passed peer review. And plenty of other studies exist. The bigger picture here is that every major health agency in the world recommends good masks such as N95s, as mentioned earlier. That is the standard for relevant healthcare workers for good reason. The experts in those agencies have looked at the studies and made that conclusion, which is the general consensus in the healthcare field. There is some chance all the experts are wrong on this. That happens sometimes. But it's rare.

by azakai 4y ago

timr 4y ago

> That is simply not true. > First, doctors and researchers consistently say that N95s are known to provide protection against Covid. I just provided you with the sum total of medical evidence supporting the claim. Citing unspecified "doctors and researchers" is not a rebuttal. You are repeating hearsay, which was exactly my point. Also, you should know that that MMWR study you've chosen to emphasize here was widely panned by scientists on both sides of the mask debate. It's based on a telephone survey with a 13% response rate. The statistics are hopelessly biased due to the test-seeking behavior of the study participants. It is not credible: https://vinayprasadmdmph.substack.com/p/mask-studies-reach-a-new-scientific https://vinayprasadmdmph.substack.com/p/mask-studies-reach-a... It's good that you pointed it out, however, because it's a perfect illustration of the abysmal level of "evidence" that has been used to support similar claims throughout the pandemic. Unfortunately, a many terrible "papers" were published and widely distributed on masks, including many in "good" journals. If you don't understand how to appraise medical evidence, you will be easily misled. > N95 masks work. It's a good idea to wear one when relevant. Unfortunately, there is no good evidence supporting this assertion, and "when relevant" is essentially unknown.

azakai 4y ago
It's not unspecified "doctors and researchers". It's the overwheming consensus among medical professionals. The CDC recommends masks, as I linked. So does the WHO, https://www.who.int/news-room/questions-and-answers/item/coronavirus-disease-covid-19-masks https://www.who.int/news-room/questions-and-answers/item/cor... And so does the European CDC, https://www.ecdc.europa.eu/en/publications-data/using-face-masks-community-reducing-covid-19-transmission https://www.ecdc.europa.eu/en/publications-data/using-face-m... etc. etc. The picture is very clear here. And, again, the lab evidence is incredibly supportive. We know that N95s filter viral particles. It's possible in theory that that doesn't end up mattering - say if people never wear them right, or if they end up taking more risks because they think they are safer - but that seems unlikely when other evidence says otherwise, and the experts concur.
- ehvatum 4y ago
  > The picture is very clear here. I wish it were. It should not be difficult to verify that N95 masks filter COVID virus particles effectively. If such a study had been performed, nobody could reasonably hypothesize that, owing to the properties of the viral envelope, an N95 filter could stop nanometer black carbon particles but not COVID viruses of the same size. It is baffling that the very basic experiment has not been done: DOES N95 FILTER COVID? The advancement of human knowledge absolutely depends on VERIFYING assumptions. Institutionalizing common beliefs without empirical data is a crime against science.
  - azakai 4y ago
    Why are you certain such studies have not been done? Plenty of things have been published in that space. For example, https://academic.oup.com/jid/article/226/2/199/6582941 https://academic.oup.com/jid/article/226/2/199/6582941 https://www.frontiersin.org/articles/10.3389/fmed.2021.654317/full https://www.frontiersin.org/articles/10.3389/fmed.2021.65431... You might respond with some specific skepticism about some particular detail in either study. But e.g. the first is in the respected Journal of Infectious Diseases. It passed peer review. And plenty of other studies exist. The bigger picture here is that every major health agency in the world recommends good masks such as N95s, as mentioned earlier. That is the standard for relevant healthcare workers for good reason. The experts in those agencies have looked at the studies and made that conclusion, which is the general consensus in the healthcare field. There is some chance all the experts are wrong on this. That happens sometimes. But it's rare.