# If anyone wasn't sure, more evidence that masks work

**URL:** <https://forum.fudiabetes.org/t/if-anyone-wasnt-sure-more-evidence-that-masks-work/9986>\
**Category:** Share\
**Created:** [July 15, 2020, 3:05pm UTC](https://forum.fudiabetes.org/t/if-anyone-wasnt-sure-more-evidence-that-masks-work/9986 "2020-07-15T15:05:27Z")\
**Posts on this page:** 20\
**Page:** 1

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**Author:** ![Chris](https://yyz2.discourse-cdn.com/flex030/user_avatar/forum.fudiabetes.org/chris/32/382_2.png) [@Chris](https://forum.fudiabetes.org/u/Chris)\
**Post date:** [July 15, 2020, 3:05pm UTC](https://forum.fudiabetes.org/t/if-anyone-wasnt-sure-more-evidence-that-masks-work/9986/1 "2020-07-15T15:05:27Z")

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2 infected hair stylists exposed 139 clients, no one got infected that they could trace.

> **[Absence of Apparent Transmission of SARS-CoV-2 from Two Stylists...](https://www.cdc.gov/mmwr/volumes/69/wr/mm6928e2.htm)**
>
> On May 12, 2020 (day 0), a hair stylist at salon A in Springfield, Missouri (stylist A), developed respiratory symptoms and continued working with clients until day 8, when the stylist received a...

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**Author:** ![docslotnick](https://yyz2.discourse-cdn.com/flex030/user_avatar/forum.fudiabetes.org/docslotnick/32/75_2.png) [@docslotnick](https://forum.fudiabetes.org/u/docslotnick)\
**Post date:** [July 15, 2020, 5:56pm UTC](https://forum.fudiabetes.org/t/if-anyone-wasnt-sure-more-evidence-that-masks-work/9986/2 "2020-07-15T17:56:20Z")

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@Chris Anecdotal. Here’s a real, annotated and reviewed study.

> **[Why Face Masks Don’t Work: A Revealing Review - Oral Health Group](https://web.archive.org/web/20170512002228/http://www.oralhealthgroup.com/features/face-masks-dont-work-revealing-review/)**
>
> Yesterday’s Scientific Dogma is Today’s Discarded Fable Introduction The above quotation is ascribed to Justice Archie Campbell author of Canada’s SARS Commission Final Report. 1 It is a stark reminder that scientific knowledge is constantly changing...

Count me as not sure.

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**Author:** ![cardamom](https://yyz2.discourse-cdn.com/flex030/user_avatar/forum.fudiabetes.org/cardamom/32/2622_2.png) [@cardamom](https://forum.fudiabetes.org/u/cardamom)\
**Post date:** [July 15, 2020, 6:14pm UTC](https://forum.fudiabetes.org/t/if-anyone-wasnt-sure-more-evidence-that-masks-work/9986/3 "2020-07-15T18:14:10Z")

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That’s hardly an academic article on the topic, just because they have references. Look at the dates on those references–it’s almost all super old research, and none of it specific to COVID transmission. I’ll take my research and recommendations relevant and up-to-date, please. The overall gist is that it’s not entirely clear the extent of protection, but evidence suggests they offer some protection and potentially enough to be significant, and that is sufficient to warrant recommending using them given this crisis.

Research:

[https://onlinelibrary.wiley.com/doi/full/10.1111/irv.12745](https://onlinelibrary.wiley.com/doi/full/10.1111/irv.12745)

> **[Face Masks Against COVID-19: An Evidence Review](https://www.preprints.org/manuscript/202004.0203/v1?fbclid=IwAR0h7PBSAB6ZEcr-DzBaTTIEV9kjvJiRZA7Eassb-rs75raKtOKIVKWcsFk)**
>
> The science around the use of masks by the general public to impede COVID-19 transmission is advancing rapidly. Policymakers need guidance on how masks should be used by the general population to combat the COVID-19 pandemic. Here, we synthesize the...

> **[The role of community-wide wearing of face mask for control of coronavirus...](https://www.sciencedirect.com/science/article/pii/S0163445320302358?casa_token=H3vOSv5c6TwAAAAA:fv7NE62KgeQq4Z5MHDhPOoQo-DJbVAShb-OhbmYILwX_1cIhJCZ7SjvD3VCZzHScKHuD9sFiwA)**
>
> Face mask usage by the healthy population in the community to reduce risk of transmission of respiratory viruses remains controversial. We assessed th…

> **[To mask or not to mask: Modeling the potential for face mask use by the...](https://www.sciencedirect.com/science/article/pii/S2468042720300117)**
>
> Face mask use by the general public for limiting the spread of the COVID-19 pandemic is controversial, though increasingly recommended, and the potent…

Recommendations published in top medical journals (vs “oral health group”):

[https://www.thelancet.com/journals/lanres/article/PIIS2213-2600(20)30134-X/fulltext?fbclid=IwAR13Xz-m-mUi-8g1O01FREbSEjl3tUxpSBiNqXufxqSaIXo0QV\_cyWu3Qx4](https://www.thelancet.com/journals/lanres/article/PIIS2213-2600(20)30134-X/fulltext?fbclid=IwAR13Xz-m-mUi-8g1O01FREbSEjl3tUxpSBiNqXufxqSaIXo0QV_cyWu3Qx4)

[https://www.bmj.com/content/369/bmj.m1435.short](https://www.bmj.com/content/369/bmj.m1435.short)

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**Author:** ![cardamom](https://yyz2.discourse-cdn.com/flex030/user_avatar/forum.fudiabetes.org/cardamom/32/2622_2.png) [@cardamom](https://forum.fudiabetes.org/u/cardamom)\
**Post date:** [July 15, 2020, 6:17pm UTC](https://forum.fudiabetes.org/t/if-anyone-wasnt-sure-more-evidence-that-masks-work/9986/4 "2020-07-15T18:17:39Z")

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Also those were just from a cursory glance at page one of results from a Google Scholar search (which you don’t need any academic credentials to use). I suggest using that if you want to examine the evidence base, vs anecdotal information.

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**Author:** ![docslotnick](https://yyz2.discourse-cdn.com/flex030/user_avatar/forum.fudiabetes.org/docslotnick/32/75_2.png) [@docslotnick](https://forum.fudiabetes.org/u/docslotnick)\
**Post date:** [July 15, 2020, 6:50pm UTC](https://forum.fudiabetes.org/t/if-anyone-wasnt-sure-more-evidence-that-masks-work/9986/5 "2020-07-15T18:50:13Z")

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@cardamom First, I don’t think the definitions of “aerosols” and “small droplet”, nor 0.1-4.0 microns have changed in the last 3 or 4 years.

And it is very insulting to cast aspersions on a Dental journal as not a valid source.

To cast doubt on a well regarded and well researched paper as a lay person shows your bias, and is hardly scientific. Refute the points in the paper if you can, don’t dismiss it out of hand because it’s four years old. That’s how **science** works.

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**Author:** ![cardamom](https://yyz2.discourse-cdn.com/flex030/user_avatar/forum.fudiabetes.org/cardamom/32/2622_2.png) [@cardamom](https://forum.fudiabetes.org/u/cardamom)\
**Post date:** [July 15, 2020, 6:54pm UTC](https://forum.fudiabetes.org/t/if-anyone-wasnt-sure-more-evidence-that-masks-work/9986/6 "2020-07-15T18:54:22Z")

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My refutation is that that paper is outdated (almost all of the _references_ it cites are over 20 years old, not just 3-4, and they certainly do not directly address any evidence of masks applying to coronavirus–the paper itself can be newer, but given it’s a review, it is only as good as the evidence it cites, which as a scientist myself, I’m well aware of), and I cited many others that are original research that more recent or reviews of recent research as my rebuttal. That is how **science** works. Maybe read a few?

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**Author:** ![Jen](https://yyz2.discourse-cdn.com/flex030/user_avatar/forum.fudiabetes.org/jen/32/4777_2.png) [@Jen](https://forum.fudiabetes.org/u/Jen)\
**Post date:** [July 15, 2020, 7:11pm UTC](https://forum.fudiabetes.org/t/if-anyone-wasnt-sure-more-evidence-that-masks-work/9986/7 "2020-07-15T19:11:03Z")

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The consensus seems to still be out. While masks may offer some benefits, they certainly aren’t a replacement for other precautionary measures. Here, masks are recommended where physical distancing is not possible, but they are not mandated. Two large Canadian cities are mandating them in indoor environments, though, so there’s a possibility that will come to my city.

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**Author:** ![ClaudnDaye](https://yyz2.discourse-cdn.com/flex030/user_avatar/forum.fudiabetes.org/claudndaye/32/5_2.png) [@ClaudnDaye](https://forum.fudiabetes.org/u/ClaudnDaye)\
**Post date:** [July 15, 2020, 7:37pm UTC](https://forum.fudiabetes.org/t/if-anyone-wasnt-sure-more-evidence-that-masks-work/9986/8 "2020-07-15T19:37:55Z")

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The best analogy that I’ve heard so far is that each precaution, individually, is like 1 single slice of swiss cheese. Each piece of cheese alone has at least one hole in it, but as you pile on more slices, one on top the other (more precautions taken simultaneously), there are less holes until, eventually there are zero holes in the stack of swiss cheese (little to no covid transmission threat). All precautions taken together will result in the least amount of transmission while none or only one precaution provides the greatest transmission rates.

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**Author:** ![Boerenkool](https://yyz2.discourse-cdn.com/flex030/user_avatar/forum.fudiabetes.org/boerenkool/32/6307_2.png) [@Boerenkool](https://forum.fudiabetes.org/u/Boerenkool)\
**Post date:** [July 15, 2020, 7:58pm UTC](https://forum.fudiabetes.org/t/if-anyone-wasnt-sure-more-evidence-that-masks-work/9986/9 "2020-07-15T19:58:51Z")

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> [@docslotnick](#):
>
> And it is very insulting to cast aspersions on a Dental journal as not a valid source.

Sorry Doc, but that particular journal is not a peer-reviewed journal. Secondly, the journal itself has removed the article, calling it no longer relevant:

> **[Update: Why Face Masks Don’t Work: A Revealing Review - Oral Health Group](https://www.oralhealthgroup.com/features/face-masks-dont-work-revealing-review/)**
>
> For at least three decades face masks has been deemed an essential component of the personal protective equipment worn by dental personnel.

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**Author:** ![docslotnick](https://yyz2.discourse-cdn.com/flex030/user_avatar/forum.fudiabetes.org/docslotnick/32/75_2.png) [@docslotnick](https://forum.fudiabetes.org/u/docslotnick)\
**Post date:** [July 15, 2020, 8:36pm UTC](https://forum.fudiabetes.org/t/if-anyone-wasnt-sure-more-evidence-that-masks-work/9986/10 "2020-07-15T20:36:18Z")

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> [@cardamom](#):
>
> almost all of the _references_ it cites are over 20 years old, not just 3-4, and they certainly do not directly address any evidence of masks applying to coronavirus

You are mistaken. The references are dated mostly 2014-2016, with one 1993. And the closest to Covid up until recently was SARS and MERS, upon which Covid recommendations were being made.

And @Boerenkool, I’m not surprised that a journal such as _Oral Health_ would remove such a controversial article in today’s climate. But it’s author and references are no less esteemed.

By all means, wear a mask if it makes you feel more secure. But don’t make the mistake of thinking that the mask is impenetrable armour.

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**Author:** ![Jen](https://yyz2.discourse-cdn.com/flex030/user_avatar/forum.fudiabetes.org/jen/32/4777_2.png) [@Jen](https://forum.fudiabetes.org/u/Jen)\
**Post date:** [July 15, 2020, 9:08pm UTC](https://forum.fudiabetes.org/t/if-anyone-wasnt-sure-more-evidence-that-masks-work/9986/11 "2020-07-15T21:08:36Z")

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From the paper’s conclusion:

“The primary reason for mandating the wearing of face masks is to protect dental personnel from airborne pathogens. This review has established that face masks are incapable of providing such a level of protection.”

Masks can lack protection at a personal level while still providing protection at a community level. I recommend reading some of the links @cardamom provided.

> [@docslotnick](#):
>
> By all means, wear a mask if it makes you feel more secure. But don’t make the mistake of thinking that the mask is impenetrable armour.

Who said that masks are an impenetrable armour? I haven’t seen that said anywhere in this thread.

The idea behind wearing masks is not that they will protect the individual wearer. The idea behind wearing masks is that they help to break the chains of transmission within communities when used in conjunction with other public health measures.

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**Author:** ![cardamom](https://yyz2.discourse-cdn.com/flex030/user_avatar/forum.fudiabetes.org/cardamom/32/2622_2.png) [@cardamom](https://forum.fudiabetes.org/u/cardamom)\
**Post date:** [July 15, 2020, 10:05pm UTC](https://forum.fudiabetes.org/t/if-anyone-wasnt-sure-more-evidence-that-masks-work/9986/12 "2020-07-15T22:05:00Z")

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> [@docslotnick](#):
>
> By all means, wear a mask if it makes you feel more secure. But don’t make the mistake of thinking that the mask is impenetrable armour.

No one is doing that. If anti-mask folks paid attention to what any mask advocates are saying, instead of creating their own bizarro reality in which masks also suppress oxygen consumption etc, they’d hear us say OVER AND OVER that **masks are worn to prevent spreading the virus not to protect people from contracting it**. It’s exactly why the only way they work effectively on a community level is when everyone wears them. Most virus spreading occurs from people who do not yet know they are infected, so to protect the community, everyone needs to assume they are infected and act accordingly. It’s why it’s not just of concern to me whether I’m wearing my mask, but it’s absolutely of concern whether everyone else is, and given how many people in the US anyway have demonstrated complete unwillingness to make this small sacrifice for community wellbeing (ironically often the same folks who claim they would sacrifice so much for this country, when it is theoretical), it is clear we need mask mandates and rules to enforce basic common sense and decency.

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**Author:** ![cardamom](https://yyz2.discourse-cdn.com/flex030/user_avatar/forum.fudiabetes.org/cardamom/32/2622_2.png) [@cardamom](https://forum.fudiabetes.org/u/cardamom)\
**Post date:** [July 15, 2020, 10:10pm UTC](https://forum.fudiabetes.org/t/if-anyone-wasnt-sure-more-evidence-that-masks-work/9986/13 "2020-07-15T22:10:28Z")

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While I would not assume these numbers to be accurate (would depend tremendously on many other factors anyway), here’s a basic illustration of the concept in case it’s easier to grasp that way:

 ![InfoGraphic-on-MASKs-scaled](https://canada1.discourse-cdn.com/flex030/uploads/fudiabetes/original/2X/8/85b5b6d3743113e8ebeed47bd997e0adab1f7e0f.jpeg)

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<div class="post-metadata">

**Author:** ![Boerenkool](https://yyz2.discourse-cdn.com/flex030/user_avatar/forum.fudiabetes.org/boerenkool/32/6307_2.png) [@Boerenkool](https://forum.fudiabetes.org/u/Boerenkool)\
**Post date:** [July 15, 2020, 10:15pm UTC](https://forum.fudiabetes.org/t/if-anyone-wasnt-sure-more-evidence-that-masks-work/9986/14 "2020-07-15T22:15:58Z")

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> [@docslotnick](#):
>
> But it’s author and references are no less esteemed.

As far as I could find, the journal is not peer-reviewed and its author hasn’t published any peer-reviewed research in at least 20 years.

> [@docslotnick](#):
>
> By all means, wear a mask if it makes you feel more secure. But don’t make the mistake of thinking that the mask is impenetrable armour.

The equivalent of the CDC in my country only recommends and mandates wearing masks in public transport. I follow that advice, so actually I don’t wear a mask that often. The thing is, I expect them to base their recommendations on actual science instead of non-peer-reviewed articles by non-researchers.

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<div class="post-metadata">

**Author:** ![Jen](https://yyz2.discourse-cdn.com/flex030/user_avatar/forum.fudiabetes.org/jen/32/4777_2.png) [@Jen](https://forum.fudiabetes.org/u/Jen)\
**Post date:** [July 15, 2020, 10:38pm UTC](https://forum.fudiabetes.org/t/if-anyone-wasnt-sure-more-evidence-that-masks-work/9986/15 "2020-07-15T22:38:33Z")

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> [@Boerenkool](#):
>
> The equivalent of the CDC in my country only recommends and mandates wearing masks in public transport. I follow that advice, so actually I don’t wear a mask that often. The thing is, I expect them to base their recommendations on actual science

Same here. Masks are recommended in indoor environments or in environments where physical distancing is not possible. Importantly, they are not recommending that masks replace other public health measures like physical distancing, hand hygiene, increased cleaning, limiting social interactions, and staying home when sick… Those things are still heavily emphasized far more than masks; masks are just another layer of protection that can help keep the virus under control.

Some people get annoyed at the changing recommendations over the past few months and claim the experts obviously don’t know what they’re talking about. But the experts are following the science as it evolves, and they are making recommendations based on the currently-available research, not on speculation, opinion, or emotion.

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**Author:** ![ClaudnDaye](https://yyz2.discourse-cdn.com/flex030/user_avatar/forum.fudiabetes.org/claudndaye/32/5_2.png) [@ClaudnDaye](https://forum.fudiabetes.org/u/ClaudnDaye)\
**Post date:** [July 15, 2020, 10:50pm UTC](https://forum.fudiabetes.org/t/if-anyone-wasnt-sure-more-evidence-that-masks-work/9986/16 "2020-07-15T22:50:43Z")

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> [@Jen](#):
>
> But the experts are following the science as it evolves, and they are making recommendations based on the currently-available research, not on speculation, opinion, or emotion.

This concept is foreign to a certain segment of the world it seems…that crazy thing called “the Scientific Method.”

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<div class="post-metadata">

**Author:** ![Chris](https://yyz2.discourse-cdn.com/flex030/user_avatar/forum.fudiabetes.org/chris/32/382_2.png) [@Chris](https://forum.fudiabetes.org/u/Chris)\
**Post date:** [July 15, 2020, 11:18pm UTC](https://forum.fudiabetes.org/t/if-anyone-wasnt-sure-more-evidence-that-masks-work/9986/17 "2020-07-15T23:18:51Z")

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The Scientific Method certainly isn’t a foreign concept to Doc, who evaluated research for his patients for years. I am just overjoyed at the subtle name calling going on in this thread when someone has an opposing view.

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**Author:** ![daisymae](https://yyz2.discourse-cdn.com/flex030/user_avatar/forum.fudiabetes.org/daisymae/32/1199_2.png) [@daisymae](https://forum.fudiabetes.org/u/daisymae)\
**Post date:** [July 15, 2020, 11:24pm UTC](https://forum.fudiabetes.org/t/if-anyone-wasnt-sure-more-evidence-that-masks-work/9986/18 "2020-07-15T23:24:28Z")

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> [@Chris](#):
>
> I am just overjoyed at the subtle name calling going on in this thread when someone has an opposing view.

I’m with you. I found it almost as fascinating…or maybe more…than the articles themselves 🤪

EDIT: OK, now I am definitely retracting my misunderstood response. I am staying clear out of this argument. This is a place for peace, enlightenment and education.

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<div class="post-metadata">

**Author:** ![ClaudnDaye](https://yyz2.discourse-cdn.com/flex030/user_avatar/forum.fudiabetes.org/claudndaye/32/5_2.png) [@ClaudnDaye](https://forum.fudiabetes.org/u/ClaudnDaye)\
**Post date:** [July 15, 2020, 11:33pm UTC](https://forum.fudiabetes.org/t/if-anyone-wasnt-sure-more-evidence-that-masks-work/9986/19 "2020-07-15T23:33:53Z")

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@Chris, i equally don’t appreciate your deciding to assume who i was talking about. My statement was a general truism and if you took it as a slight against someone specifically then that’s on you. I think you know me well enough now to know i hold no punches. If i have something to say to you, doc or anyone else I’ll call you out by name. I’m surprised you don’t know that about me by now.

I don’t even read his posts as he’s on ignore. Shame on you for furthering the divide with your assumptions.

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<div class="post-metadata">

**Author:** ![Chris](https://yyz2.discourse-cdn.com/flex030/user_avatar/forum.fudiabetes.org/chris/32/382_2.png) [@Chris](https://forum.fudiabetes.org/u/Chris)\
**Post date:** [July 15, 2020, 11:36pm UTC](https://forum.fudiabetes.org/t/if-anyone-wasnt-sure-more-evidence-that-masks-work/9986/20 "2020-07-15T23:36:48Z")

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Well thank you for correcting the record. I appreciate your explanation, but if you think I am fanning the flames of furthering a divide on this site, I don’t even know what to say.

[Next page](https://forum.fudiabetes.org/t/if-anyone-wasnt-sure-more-evidence-that-masks-work/9986.md?page=2)
