16 ms·

It's pretty conclusive. It's been conclusive for years and years, before COVID-19. There's no question at all that masks reduce infectiousness through the extre

It's pretty conclusive. It's been conclusive for years and years, before COVID-19. There's no question at all that masks reduce infectiousness through the extremely obvious method of preventing some virus particles from going from one person to another, and also no question at all that probability of infection depends on number of virus particles around, and that viruses in general produce worse symptoms when the initial viral load is higher (and masks reduce the initial viral load via the extraordinarily obvious physical mechanism). You will find literally zero papers credibly claiming otherwise. You will find many papers claiming that masks do not reduce the risk to zero. That's obvious and also irrelevant in light of the above. You will find papers claiming that random cloth masks do not negligibly reduce the risk when you're immersed in a high-virus-density environment for hours on end. Not as obvious, but also irrelevant in light of the above. If you think you know of a paper that contradicts the above, send it our way please.

miles 5y ago
> It's been conclusive for years and years, before COVID-19. March 2020: U.S. health officials say Americans shouldn’t wear face masks to prevent coronavirus https://www.marketwatch.com/story/the-cdc-says-americans-dont-have-to-wear-facemasks-because-of-coronavirus-2020-01-30 https://www.marketwatch.com/story/the-cdc-says-americans-don... In fact the U.S. surgeon general recently urged the public to “STOP BUYING MASKS!” “They are NOT effective in preventing general public from catching #Coronavirus, but if healthcare providers can’t get them to care for sick patients, it puts them and our communities at risk!,” wrote Surgeon General Jerome Adams on Twitter. The CDC said last month it doesn’t recommend people use face masks, making the announcement on the same day that first case of person-to-person transmission of coronavirus was reported in the U.S. The CDC recommendation on masks stands, a spokesman told MarketWatch Wednesday, even with the first reported case of a COVID-19 infection in an individual in California who had not been to China or been exposed to a person diagnosed with the virus. “The virus is not spreading in the general community,” Dr. Nancy Messonnier, director of the Center for the National Center for Immunization and Respiratory Diseases, said in a Jan. 30 briefing. “We don’t routinely recommend the use of face masks by the public to prevent respiratory illness. And we certainly are not recommending that at this time for this new virus.” WHO stands by recommendation to not wear masks if you are not sick or not caring for someone who is sick https://www.cnn.com/2020/03/30/world/coronavirus-who-masks-recommendation-trnd/index.html https://www.cnn.com/2020/03/30/world/coronavirus-who-masks-r... “There is no specific evidence to suggest that the wearing of masks by the mass population has any potential benefit. In fact, there’s some evidence to suggest the opposite in the misuse of wearing a mask properly or fitting it properly,” Dr. Mike Ryan, executive director of the WHO health emergencies program, said at a media briefing in Geneva, Switzerland, on Monday.
- Valectar 5y ago
  So, you linked a number of articles from early 2020, when there was not significant community spread of COVID and thus the primary strategy for dealing with it was isolating and quarantining individual cases, and most people in the country would probably not come in to contact with someone carrying COVID. If you want to know what the WHO recommends, you need only look at their website: https://www.who.int/emergencies/diseases/novel-coronavirus-2019/advice-for-public/when-and-how-to-use-masks https://www.who.int/emergencies/diseases/novel-coronavirus-2... "Make wearing a mask a normal part of being around other people. The appropriate use, storage and cleaning or disposal of masks are essential to make them as effective as possible."
- Rebelgecko 5y ago
  The CDC made that statement because masks work. It was worded dumbly, but they're just saying that when the mask supply is constrained, healthcare workers should be prioritized over the general public. If masks didn't work, there'd be no point in triaging who gets them.
leereeves 5y ago
It wasn't hard to find sources that disagree: > The use of masks, which are medical devices, requires correct use, based on medical principles unfortunately not known by the whole population. This cultural deficiency, linked to the breathing difficulties caused by the use of this filter, has led to incorrect management of these important medical devices, facilitating the commission of errors that can make the masks ineffective or *even dangerous because they can become a vehicle for the spread of the disease itself*. https://www.sciencedirect.com/science/article/pii/S0925753520303945#b0015 https://www.sciencedirect.com/science/article/pii/S092575352... That article cites a WHO statement: > Using a mask incorrectly however, may actually increase the risk of transmission, rather than reduce it. https://www.who.int/csr/resources/publications/Adviceusemaskscommunityrevised.pdf https://www.who.int/csr/resources/publications/Adviceusemask... Edit: what is wrong with people here, downvoting quotes from scientific articles and WHO statements, because they don't like what they say?
- omegaworks 5y ago
  >Using a mask incorrectly however, may actually increase the risk of transmission, rather than reduce it. Read your link. Proper usage isn't hard to understand. If you touch your mask with your dirty hands it might increase the chance that you breathe in the germs that were on your hands. Don't put a dirty mask on your face. Don't touch your mask with dirty hands. Notice that these messages are different than "masks are a mind-control conspiracy" and "masks are ineffective."
  - leereeves 5y ago
    I see people misusing masks all the time. Read the CDC guidance on masks and check out how many people follow it: > A mask is NOT a substitute for social distancing. > Masks should completely cover the nose and mouth and fit snugly against the sides of face without gaps. [People with beards should closely trim their beard or wear two masks] > Wash your hands with soap and water for at least 20 seconds or use hand sanitizer with at least 60% alcohol after touching or removing your mask. > Not recommended: Masks that do not fit properly, masks made from fabric that is loosely woven, masks with one layer, masks with exhalation valves or vents. https://www.cdc.gov/coronavirus/2019-ncov/prevent-getting-sick/cloth-face-cover-guidance.html https://www.cdc.gov/coronavirus/2019-ncov/prevent-getting-si...
__blockcipher__ 5y ago
> It's been conclusive for years and years, before COVID-19 What? The overwhelming literature showed the exact opposite! That cloth masks did not prevent Influenza whatsoever. I'd start with https://aapsonline.org/mask-facts/ https://aapsonline.org/mask-facts/ as a great review, and then take a look at some specific studies like this one: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4420971/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4420971/ > The rates of all infection outcomes were highest in the cloth mask arm, with the rate of ILI statistically significantly higher in the cloth mask arm (relative risk (RR)=13.00, 95% CI 1.69 to 100.07) compared with the medical mask arm. Cloth masks also had significantly higher rates of ILI compared with the control arm. An analysis by mask use showed ILI (RR=6.64, 95% CI 1.45 to 28.65) and laboratory-confirmed virus (RR=1.72, 95% CI 1.01 to 2.94) were significantly higher in the cloth masks group compared with the medical masks group. Penetration of cloth masks by particles was almost 97% and medical masks 44%. > This study is the first RCT of cloth masks, and the results caution against the use of cloth masks. > The control arm was ‘standard practice’, which comprised mask use in a high proportion of participants. As such (without a no-mask control), the finding of a much higher rate of infection in the cloth mask arm could be interpreted as harm caused by cloth masks, efficacy of medical masks, or most likely a combination of both. --- The TL;DR is masks were never thought to work for community transmission of any respiratory virus, but they definitely don't work for SARS-2 where the preponderance of evidence points to aerosol transmission as the dominant transmission mode, which masks cannot help against and could theoretically worsen (by increasing the total quantity of aerosols released, and that's before looking at factors like them giving a false sense of security or requiring conversational partners to stand more closely together)
- Valectar 5y ago
  Where did your conclusion of "masks definitely don't work for SARS-2" come from? Just in your quote it stated that the control that cloth mask use was compared to was a population with a high proportion of mask wearing. The study does not compare cloth mask usage to no mask usage, and only says that it is possible that cloth masks are harmful. Also if you would like some more up to date information, as well as a larger number of studied, which are specific to COVID, the CDC website has a lot of information here: https://www.cdc.gov/coronavirus/2019-ncov/science/science-briefs/masking-science-sars-cov2.html https://www.cdc.gov/coronavirus/2019-ncov/science/science-br...
timr 5y ago
> You will find literally zero papers credibly claiming otherwise. Of the papers cited in the WHO meta-analysis of face masks and infection [1], all of the (three!) papers from a non-health-care setting had a confidence interval overlapping 1.0 (i.e. "no benefit"). Of those in a health-care setting, about half had confidence intervals overlapping 1.0 (i.e. "no benefit"): https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(20)31142-9/fulltext#seccestitle140 https://www.thelancet.com/journals/lancet/article/PIIS0140-6... The literature in this area was exceptionally ambiguous prior to 2020, and hasn't improved over the course of the pandemic. You've just made a provably incorrect claim. If you did it on YouTube, I guess you'd be banned! (just kidding; we all know that you can't possibly misinform people when you're agreeing with the party line!) [1] https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(20)31142-9/fulltext#seccestitle140 https://www.thelancet.com/journals/lancet/article/PIIS0140-6...
- nickthemagicman 5y ago
  Thanks for posting. No one on the pro-mask side reads scientific papers. They're fascists and want to crush their opposition through controlling the narrative instead of actual science.
- kgarten 5y ago
  Anecdotal, how do you explain the non existing flue season (last autumn ) and the low incidences in Japan? We got higher rates during the Olympic. I live in Tokyo, Japan and visit US/Europe often. The only significant difference I see is the willingness to wear masks. And there's way less space here (packed subways etc.)
  - timr 5y ago
    Well, any rational conversation about Japan has to start with the observation that cases are at an all-time high right now: https://www.asahi.com/topics/word/%E3%82%B3%E3%83%AD%E3%83%8A%E3%82%A6%E3%82%A4%E3%83%AB%E3%82%B9.html?iref=evb_1 https://www.asahi.com/topics/word/%E3%82%B3%E3%83%AD%E3%83%8... I don't think changing rates of masking can explain that change. > Anecdotal, how do you explain the non existing flue season (last autumn ) and the low incidences in Japan? We got higher rates during the Olympic. I haven't seen any data on flu during the olympics, so I can't comment on that. Covid cases, of course, were shooting up long before the first athletes even arrived in Japan (see above). To answer your question, nobody knows why flu "disappeared" during the last year. My hypothesis is a combination of two things: 1) it didn't disappear, it just spread less due to to the dramatic reduction in international travel (plus maybe closure of schools). 2) we stopped testing for flu at rates necessary to detect it. Our prior surveillance system for influenza was pretty limited, and most of it switched to Covid in 2020. In general, I think people fixate on masks far too much, because they're visible. Even in Japan, what qualifies as a mask would make Americans in the "mask compliant" cities laugh out loud. I routinely see people wearing these on Instagram and on television: https://www.superdelivery.com/product_image/812/8/8128738_1000.jpg https://www.superdelivery.com/product_image/812/8/8128738_10...
nickthemagicman 5y ago
> It's pretty conclusive. It's been conclusive for years and years * Citation needed Pro-maskers think that if they tell people they can fly it's others responsibility to prove that they can't fly. The burden of proof is on the people claiming that something works. Do you not understand how science works? You're saying is 'conclusive' that masks work. I'm saying you are disengenuouslty parroting media talking points and have to post a scientific paper to prove your claim. Every paper you will find has flaws and contradiction and inconclusivities. Texas lifted all Covid restrictions including masks and has lower infection rates per capita than states with mask mandates. Clearly it's not conclusive.
nickthemagicman 5y ago
> You will find literally zero papers credibly claiming otherwise. Here's a paper that says cloth mask usage increases rate of infection. https://bmjopen.bmj.com/content/5/4/e006577 https://bmjopen.bmj.com/content/5/4/e006577 Here's a collection of studies refuting mask efficacy. https://swprs.org/face-masks-evidence/ https://swprs.org/face-masks-evidence/ You're literally a vector for disinformation which is a bannable offense but only the Rand Pauls who go against the narrative get banned. Your false information you just posted will be celebrated by the echo chamber members of the internet.
- sampo 5y ago
  > Here's a paper that says cloth mask usage increases rate of infection. > https://bmjopen.bmj.com/content/5/4/e006577 https://bmjopen.bmj.com/content/5/4/e006577 Using cloth masks only, increased rate of infection in relation to the control group. And the control group: "In the control arm, 170/458 (37%) used medical masks, 38/458 (8%) used cloth masks, and 245/458 (53%) used a combination of both medical and cloth masks during the study period." So we can conclude that the medical masks, used in the control arm, worked better than cloth masks. If you were trying to coyly imply that the study said that cloth masks increased infections compared to using no mask at all, you were being dishonest.
  - nickthemagicman 5y ago
    Read that paper again. Cloth mask wearers had a higher rate of CLI than the control group. The control group being may or may not be wearing a mask. """The control arm was ‘standard practice’, which comprised mask use in a high proportion of participants. As such (without a no-mask control), the finding of a much higher rate of infection in the cloth mask arm could be interpreted as harm caused by cloth masks, efficacy of medical masks, or most likely a combination of both.""" Point is: The CDC mask policy of wearing a dirty cloth rag on your face until the waiter brings the breadsticks is probably not ideal.

miles 5y ago

> It's been conclusive for years and years, before COVID-19. March 2020: U.S. health officials say Americans shouldn’t wear face masks to prevent coronavirus https://www.marketwatch.com/story/the-cdc-says-americans-dont-have-to-wear-facemasks-because-of-coronavirus-2020-01-30 https://www.marketwatch.com/story/the-cdc-says-americans-don... In fact the U.S. surgeon general recently urged the public to “STOP BUYING MASKS!” “They are NOT effective in preventing general public from catching #Coronavirus, but if healthcare providers can’t get them to care for sick patients, it puts them and our communities at risk!,” wrote Surgeon General Jerome Adams on Twitter. The CDC said last month it doesn’t recommend people use face masks, making the announcement on the same day that first case of person-to-person transmission of coronavirus was reported in the U.S. The CDC recommendation on masks stands, a spokesman told MarketWatch Wednesday, even with the first reported case of a COVID-19 infection in an individual in California who had not been to China or been exposed to a person diagnosed with the virus. “The virus is not spreading in the general community,” Dr. Nancy Messonnier, director of the Center for the National Center for Immunization and Respiratory Diseases, said in a Jan. 30 briefing. “We don’t routinely recommend the use of face masks by the public to prevent respiratory illness. And we certainly are not recommending that at this time for this new virus.” WHO stands by recommendation to not wear masks if you are not sick or not caring for someone who is sick https://www.cnn.com/2020/03/30/world/coronavirus-who-masks-recommendation-trnd/index.html https://www.cnn.com/2020/03/30/world/coronavirus-who-masks-r... “There is no specific evidence to suggest that the wearing of masks by the mass population has any potential benefit. In fact, there’s some evidence to suggest the opposite in the misuse of wearing a mask properly or fitting it properly,” Dr. Mike Ryan, executive director of the WHO health emergencies program, said at a media briefing in Geneva, Switzerland, on Monday.

Valectar 5y ago
So, you linked a number of articles from early 2020, when there was not significant community spread of COVID and thus the primary strategy for dealing with it was isolating and quarantining individual cases, and most people in the country would probably not come in to contact with someone carrying COVID. If you want to know what the WHO recommends, you need only look at their website: https://www.who.int/emergencies/diseases/novel-coronavirus-2019/advice-for-public/when-and-how-to-use-masks https://www.who.int/emergencies/diseases/novel-coronavirus-2... "Make wearing a mask a normal part of being around other people. The appropriate use, storage and cleaning or disposal of masks are essential to make them as effective as possible."
Rebelgecko 5y ago
The CDC made that statement because masks work. It was worded dumbly, but they're just saying that when the mask supply is constrained, healthcare workers should be prioritized over the general public. If masks didn't work, there'd be no point in triaging who gets them.

leereeves 5y ago

It wasn't hard to find sources that disagree: > The use of masks, which are medical devices, requires correct use, based on medical principles unfortunately not known by the whole population. This cultural deficiency, linked to the breathing difficulties caused by the use of this filter, has led to incorrect management of these important medical devices, facilitating the commission of errors that can make the masks ineffective or *even dangerous because they can become a vehicle for the spread of the disease itself*. https://www.sciencedirect.com/science/article/pii/S0925753520303945#b0015 https://www.sciencedirect.com/science/article/pii/S092575352... That article cites a WHO statement: > Using a mask incorrectly however, may actually increase the risk of transmission, rather than reduce it. https://www.who.int/csr/resources/publications/Adviceusemaskscommunityrevised.pdf https://www.who.int/csr/resources/publications/Adviceusemask... Edit: what is wrong with people here, downvoting quotes from scientific articles and WHO statements, because they don't like what they say?

omegaworks 5y ago
>Using a mask incorrectly however, may actually increase the risk of transmission, rather than reduce it. Read your link. Proper usage isn't hard to understand. If you touch your mask with your dirty hands it might increase the chance that you breathe in the germs that were on your hands. Don't put a dirty mask on your face. Don't touch your mask with dirty hands. Notice that these messages are different than "masks are a mind-control conspiracy" and "masks are ineffective."
- leereeves 5y ago
  I see people misusing masks all the time. Read the CDC guidance on masks and check out how many people follow it: > A mask is NOT a substitute for social distancing. > Masks should completely cover the nose and mouth and fit snugly against the sides of face without gaps. [People with beards should closely trim their beard or wear two masks] > Wash your hands with soap and water for at least 20 seconds or use hand sanitizer with at least 60% alcohol after touching or removing your mask. > Not recommended: Masks that do not fit properly, masks made from fabric that is loosely woven, masks with one layer, masks with exhalation valves or vents. https://www.cdc.gov/coronavirus/2019-ncov/prevent-getting-sick/cloth-face-cover-guidance.html https://www.cdc.gov/coronavirus/2019-ncov/prevent-getting-si...

__blockcipher__ 5y ago

> It's been conclusive for years and years, before COVID-19 What? The overwhelming literature showed the exact opposite! That cloth masks did not prevent Influenza whatsoever. I'd start with https://aapsonline.org/mask-facts/ https://aapsonline.org/mask-facts/ as a great review, and then take a look at some specific studies like this one: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4420971/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4420971/ > The rates of all infection outcomes were highest in the cloth mask arm, with the rate of ILI statistically significantly higher in the cloth mask arm (relative risk (RR)=13.00, 95% CI 1.69 to 100.07) compared with the medical mask arm. Cloth masks also had significantly higher rates of ILI compared with the control arm. An analysis by mask use showed ILI (RR=6.64, 95% CI 1.45 to 28.65) and laboratory-confirmed virus (RR=1.72, 95% CI 1.01 to 2.94) were significantly higher in the cloth masks group compared with the medical masks group. Penetration of cloth masks by particles was almost 97% and medical masks 44%. > This study is the first RCT of cloth masks, and the results caution against the use of cloth masks. > The control arm was ‘standard practice’, which comprised mask use in a high proportion of participants. As such (without a no-mask control), the finding of a much higher rate of infection in the cloth mask arm could be interpreted as harm caused by cloth masks, efficacy of medical masks, or most likely a combination of both. --- The TL;DR is masks were never thought to work for community transmission of any respiratory virus, but they definitely don't work for SARS-2 where the preponderance of evidence points to aerosol transmission as the dominant transmission mode, which masks cannot help against and could theoretically worsen (by increasing the total quantity of aerosols released, and that's before looking at factors like them giving a false sense of security or requiring conversational partners to stand more closely together)

Valectar 5y ago
Where did your conclusion of "masks definitely don't work for SARS-2" come from? Just in your quote it stated that the control that cloth mask use was compared to was a population with a high proportion of mask wearing. The study does not compare cloth mask usage to no mask usage, and only says that it is possible that cloth masks are harmful. Also if you would like some more up to date information, as well as a larger number of studied, which are specific to COVID, the CDC website has a lot of information here: https://www.cdc.gov/coronavirus/2019-ncov/science/science-briefs/masking-science-sars-cov2.html https://www.cdc.gov/coronavirus/2019-ncov/science/science-br...

timr 5y ago

> You will find literally zero papers credibly claiming otherwise. Of the papers cited in the WHO meta-analysis of face masks and infection [1], all of the (three!) papers from a non-health-care setting had a confidence interval overlapping 1.0 (i.e. "no benefit"). Of those in a health-care setting, about half had confidence intervals overlapping 1.0 (i.e. "no benefit"): https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(20)31142-9/fulltext#seccestitle140 https://www.thelancet.com/journals/lancet/article/PIIS0140-6... The literature in this area was exceptionally ambiguous prior to 2020, and hasn't improved over the course of the pandemic. You've just made a provably incorrect claim. If you did it on YouTube, I guess you'd be banned! (just kidding; we all know that you can't possibly misinform people when you're agreeing with the party line!) [1] https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(20)31142-9/fulltext#seccestitle140 https://www.thelancet.com/journals/lancet/article/PIIS0140-6...

nickthemagicman 5y ago
Thanks for posting. No one on the pro-mask side reads scientific papers. They're fascists and want to crush their opposition through controlling the narrative instead of actual science.
kgarten 5y ago
Anecdotal, how do you explain the non existing flue season (last autumn ) and the low incidences in Japan? We got higher rates during the Olympic. I live in Tokyo, Japan and visit US/Europe often. The only significant difference I see is the willingness to wear masks. And there's way less space here (packed subways etc.)
- timr 5y ago
  Well, any rational conversation about Japan has to start with the observation that cases are at an all-time high right now: https://www.asahi.com/topics/word/%E3%82%B3%E3%83%AD%E3%83%8A%E3%82%A6%E3%82%A4%E3%83%AB%E3%82%B9.html?iref=evb_1 https://www.asahi.com/topics/word/%E3%82%B3%E3%83%AD%E3%83%8... I don't think changing rates of masking can explain that change. > Anecdotal, how do you explain the non existing flue season (last autumn ) and the low incidences in Japan? We got higher rates during the Olympic. I haven't seen any data on flu during the olympics, so I can't comment on that. Covid cases, of course, were shooting up long before the first athletes even arrived in Japan (see above). To answer your question, nobody knows why flu "disappeared" during the last year. My hypothesis is a combination of two things: 1) it didn't disappear, it just spread less due to to the dramatic reduction in international travel (plus maybe closure of schools). 2) we stopped testing for flu at rates necessary to detect it. Our prior surveillance system for influenza was pretty limited, and most of it switched to Covid in 2020. In general, I think people fixate on masks far too much, because they're visible. Even in Japan, what qualifies as a mask would make Americans in the "mask compliant" cities laugh out loud. I routinely see people wearing these on Instagram and on television: https://www.superdelivery.com/product_image/812/8/8128738_1000.jpg https://www.superdelivery.com/product_image/812/8/8128738_10...

nickthemagicman 5y ago

> It's pretty conclusive. It's been conclusive for years and years * Citation needed Pro-maskers think that if they tell people they can fly it's others responsibility to prove that they can't fly. The burden of proof is on the people claiming that something works. Do you not understand how science works? You're saying is 'conclusive' that masks work. I'm saying you are disengenuouslty parroting media talking points and have to post a scientific paper to prove your claim. Every paper you will find has flaws and contradiction and inconclusivities. Texas lifted all Covid restrictions including masks and has lower infection rates per capita than states with mask mandates. Clearly it's not conclusive.

nickthemagicman 5y ago

> You will find literally zero papers credibly claiming otherwise. Here's a paper that says cloth mask usage increases rate of infection. https://bmjopen.bmj.com/content/5/4/e006577 https://bmjopen.bmj.com/content/5/4/e006577 Here's a collection of studies refuting mask efficacy. https://swprs.org/face-masks-evidence/ https://swprs.org/face-masks-evidence/ You're literally a vector for disinformation which is a bannable offense but only the Rand Pauls who go against the narrative get banned. Your false information you just posted will be celebrated by the echo chamber members of the internet.

sampo 5y ago
> Here's a paper that says cloth mask usage increases rate of infection. > https://bmjopen.bmj.com/content/5/4/e006577 https://bmjopen.bmj.com/content/5/4/e006577 Using cloth masks only, increased rate of infection in relation to the control group. And the control group: "In the control arm, 170/458 (37%) used medical masks, 38/458 (8%) used cloth masks, and 245/458 (53%) used a combination of both medical and cloth masks during the study period." So we can conclude that the medical masks, used in the control arm, worked better than cloth masks. If you were trying to coyly imply that the study said that cloth masks increased infections compared to using no mask at all, you were being dishonest.
- nickthemagicman 5y ago
  Read that paper again. Cloth mask wearers had a higher rate of CLI than the control group. The control group being may or may not be wearing a mask. """The control arm was ‘standard practice’, which comprised mask use in a high proportion of participants. As such (without a no-mask control), the finding of a much higher rate of infection in the cloth mask arm could be interpreted as harm caused by cloth masks, efficacy of medical masks, or most likely a combination of both.""" Point is: The CDC mask policy of wearing a dirty cloth rag on your face until the waiter brings the breadsticks is probably not ideal.