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Masks don’t work to stop COVID, though they work wonders keeping kids out of school & unemployment high

But WHY don’t they work? Let’s see

Rather than thinking of respiratory aerosols like tiny spit globules, a better metaphor is cigarette smoke

https://twitter.com/Emily_Burns_V/status/1377064164091437060
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Cigarette smoke is almost the exact same size as 99% of virus-carrying breath aerosols-- <1 micron. The majority of these particles are in the 0.2 – 0.25 micron range--just like the majority of breath aerosols.

https://www.sciencedirect.com/science/article/abs/pii/0095852260900374#:~:text=From%20these%20measurements%20it%20was,between%200.2%20and%200.25%20micron
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This is the EXACT range of breath aerosols. The chart below shows that out of around 11K breath aerosols generated during 5” of breathing, only about 25 are over 1 micron~0.02%. 90% are <0.3 microns—the exact same size & distribution as cigarette smoke.
https://www.pnas.org/content/118/8/e2021830118
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Rather than thinking of the breath aerosols as being forced THROUGH the mask, it’s better to think of the mask as being non-porous—a barrier that redirects the aerosols. They aren’t filtered, b/c the force of exhalation pushes them out the nearest gap
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Way back in 2008, they found that only 0.1% of virus-carrying aerosols were larger than 5 microns, and that 87% of the virus was carried in particles <1 micron—which happens to map exactly to the size distribution of aerosols

https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0002691
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There has been this idea that masks must help a little, because they filter at least the larger aerosols. If there were an even distribution of aerosols by size, this would make sense. But it’s not. There are 100x more aerosols <1 micron than over.

https://www.pnas.org/content/118/8/e2021830118
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Additionally, we see that when the viral load peaks, around 7 days, aerosols <0.3 microns increase by 10-fold—to almost 100K. And those over 1 micron drop below 10. https://www.pnas.org/content/118/8/e2021830118
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The going theory is that this change occurs due to inflammation of the alveoli. This might explain why asymptomatic people infect others @ a lower rate (~0.7% vs. ~18%) b/c presumably, lacking inflammation, they would generate 10x fewer aerosols.
https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2774102?fbclid=IwAR3vVRho5wmJDDuwvlxOUnIoSpVGaV2AIoPX7rEa_TtLmNVtVMxopnM8XdE
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What you just witnessed is actually consistent with mechanistic studies that show that various masks CAN help to slow the spread. Those studies show that even an N-95 drops down to ~12% efficacy with only a 1% gap (equivalent to 1 mm on the sides).

https://pubs.acs.org/doi/10.1021/acsnano.0c03252
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Let’s look at a non-fit-tested KN-95. I tried to make it a close fit, but as you can see, the smoke still goes right out the top.
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While doing this, I found that when I inhaled, due to the negative pressure created, I felt the seal tighten, where exhaling I could feel the breath forcing through the gaps. This may explain why N-95s help to protect, but don’t seem to impact transmission.
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The CDC has recently recommended double-masking—no doubt inspired by the mechanistic study performed by ACS referenced above.

Let’s try that, and see if that helps to keep the cigarette smoke in (which again, is the same size as respiratory aerosols).
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Why though? In the study, the CDC notes that double masking captured 87% of respiratory aerosols. The size range was 0.01 micron to 7 microns. Here’s the problem. The measured the VOLUME of the aerosols captured. https://www.cdc.gov/mmwr/volumes/70/wr/mm7007e1.htm
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The volume of a 7 micron aerosol is 12,000 times more than the volume of a 0.3 micron aerosol. So while aerosols over 1 micron make up less than 0.1%, and carry less than 0.1% of the virus, they make up 93% of the VOLUME of aerosols generated.
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Which is these mechanistic studies are so flawed—and indeed why clinical trials have shown repeatedly that in real life, masks do not work to impact viral transmission.

https://wwwnc.cdc.gov/eid/article/26/5/19-0994_article?fbclid=IwAR0B5G7uCEL5gOKB989joPmiH75VfzGsFdlUl0QSIsd3wET3uxGZl7Bf120
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None of this should have come as a surprise. We have known this for decades. As far back as 1980, a very elegant experiment placed a tracer particle on the inside of a surgical mask. EVERY SINGLE TIME the particle was found IN the wound.

https://pubmed.ncbi.nlm.nih.gov/7379387/ 
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A 2016 review noted that even in for their main purpose—decreasing wound infection during surgery—surgical masks have no impact. But this purpose is to stop much larger particles than the smoke-sized aerosols that drive COVID transmission.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7138271/#:~:text=All%20three%20studies%20showed%20that,wound%20infections%20developing%20after%20surgery.
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The breath aerosols that drive transmission of COVID and other respiratory viruses are virtually un-filterable

https://www.liebertpub.com/doi/10.1089/jamp.2020.1616
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Which explains why even N-95s, while again, showing good mechanistic data, do not appear to have an impact on actually reducing illness.

https://pubmed.ncbi.nlm.nih.gov/23418400/ 
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It is for this reason that people who are serious have raised alarms about the ability of N-95s to protect healthcare worker, and who have given voice to the importance of ventilation.
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Ultimately, just like incessant sanitizing to remove fomites, the 6 feet rule, etc. masks are just another part of the pandemic theater which seems to be the CDC’s raison d’être, creating panic to justify its existence. https://www.yahoo.com/now/end-the-hygiene-theater-cdc-says-173440864.html
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Now as the pandemic recedes, it is fear that is the pandemic.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4868614/
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Masks have become a symbol of right-think, no doubt why masking has its highest correlation with BLM support. But at the same time, the fear that masks symbolize cause acute harms—low in-person education and high unemployment. https://twitter.com/Emily_Burns_V/status/1377066067122655233
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At the same time, these policies, supported most vocally by those in states who claim to care about social justice, result in kids in districts with high minority enrollment being educated 100% virtually at ~4-5x the rate as largely white districts.
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The harm does not stop there.

Masking is associated with significant increases in fear of illness, physical isolation, and feeling isolated.
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All to no end. It is time for the CDC to end this theatre as well. Every day that this dissonance between these measures and reality continues, medicine, public health and the government lose credibility. Every day it continues, people are harmed. https://twitter.com/Emily_Burns_V/status/1377066921733070848
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People DO believe that doctors and public health officials are smart. Thus, “incompetence” is not the answer they arrive at. They begin to suspect sinister motives—this is how conspiracy theories are planted and nurtured.
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It would be far better for American Public Health to acknowledge their failures. Doing so would actually work to create far more trust in them than the pointless dissembling that is occurring now.
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Of the many, many failures of American Public Health throughout this pandemic, few actions are more disgusting than the deliberate shifting of blame for their failed policies onto the American Public itself.
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The deliberate demonization of those who point to the manifest inefficacy of their policies is causing real moral corrosion of the populace. It is unthinkable that any public health establishment would stoke this kind of dehumanization of the public it "serves."
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The vaccines work, and they work extraordinarily well at protecting those who are at real risk. Those people are almost all vaccinated at this point. It is time to be done with these pointless restrictions—especially the masks.
https://mobile.twitter.com/Emily_Burns_V/status/1382919192748363776
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