7 ms·

Face masks couldn’t be doing that because they don’t work to slow transmission whatsoever. The whole theory of face masks - even before accounting for real worl

Face masks couldn’t be doing that because they don’t work to slow transmission whatsoever. The whole theory of face masks - even before accounting for real world usage - rests on the assumption that the primary transmission mode is respiratory droplets and not aerosols which is not the case. They’re just medical security theater, except worse because they have obvious negatives. I advocate instead for performing rain dances; they’re no less effective but provide a bit of exercise to boot. Anyway, on a related vein, non-infection-protecting vaccines can do exactly what you’re saying and select for more virulent/pathogenic strains. Take a look: https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.1002198 https://journals.plos.org/plosbiology/article?id=10.1371/jou.... Because all the COVID/19 vaccines do not prevent infection nor transmission (they reduce it but don’t fully block it), our incredibly shortsighted mass vaccination campaign is likely to select for more pathogenic strains. Go science! > Could some vaccines drive the evolution of more virulent pathogens? Conventional wisdom is that natural selection will remove highly lethal pathogens if host death greatly reduces transmission. Vaccines that keep hosts alive but still allow transmission could thus allow very virulent strains to circulate in a population. Here we show experimentally that immunization of chickens against Marek's disease virus enhances the fitness of more virulent strains, making it possible for hyperpathogenic strains to transmit. Immunity elicited by direct vaccination or by maternal vaccination prolongs host survival but does not prevent infection, viral replication or transmission, thus extending the infectious periods of strains otherwise too lethal to persist. Our data show that anti-disease vaccines that do not prevent transmission can create conditions that promote the emergence of pathogen strains that cause more severe disease in unvaccinated hosts.

sterlind 5y ago
we should be pushing for N95 masks to be cheaper and more available. those masks block aerosols when they're properly fitted (and we should make them easier to fit.)
- __blockcipher__ 5y ago
  I would love for N95 usage to become more widespread, but that is hampered by the dogmatic clinging to the belief that cloth masks actually work, unfortunately. Do N95s work for source control though? They certainly do work for self infection but I haven’t personally read any N95 studies on source control so am not sure.
  - sterlind 5y ago
    the ones without exhalation valves do. the barrier is bidirectional. the ones with valves bypass this which is why those shouldn't be used for source control but are popular for wildfires etc.
    - __blockcipher__ 5y ago
      Thanks. That was my thinking but glad to see it confirmed. Kind of ironic that you’re not allowed to wear an N95 with an exhale valve, but are encouraged to wear a surgical mask, bandana, cloth mask, or dirty T-shirt, none of which provide any source control. Again, the elephant in the room is respiratory viruses in general, and SARS-2 in particular, spread via aerosols. Non-N95 face coverings cannot block aerosols. Indeed mask wearing leads to deeper breaths to maintain homeostasis (this has been studied), therefore lead to a greater net volume of air, therefore lead to increased aerosol emission before even accounting for the potential to nebulize large droplets into a shower of tiny aerosol particles. But I digress.
      - loosescrews 5y ago
        A surgical mask, bandana, cloth mask, or dirty T-shirt over a particulate mask (e.g. N95) is typically allowed. There are serious benefits to the wearer to having an exhaust valve. Wearing a second, less effective face covering over the particulate mask retains the benefits of the particulate mask and exhaust valve while maintaining the same level of source control as without the particulate mask.
  - arrrg 5y ago
    Where are you from that FFP2 usage is not common? Sure, cloth masks were widespread for about a year but by now usage of FFP2 masks is becoming extremely widespread, especially since the supply is by now overwhelming.
- nyokodo 5y ago
  > and we should make them easier to fit Not to mention make versions for unusual face sizes (big and small). I cannot find one large enough for my face.
  - Tor3 5y ago
    And my wife can't find ones small enough to fit her face properly. In her home country masks come in all sizes and shapes, in Europe there seems to be only a single size. At least every type I've looked at is the same size as all the others.
  - godelmachine 5y ago
    3M N95 9210 should be big enough to cover anyone's face, methinks.
    - Semaphor 5y ago
      They are also pretty expensive for a single-use product.
      - godelmachine 5y ago
        They are but I believe to will protect anyone extremely well.
  - Semaphor 5y ago
    I found one with an amazing fit from China that was large enough. Then I googled the name and found out it’s listed under the fake/mislabeled category on the CDC site [0] with filtration efficiency between 8 and 94% (over 2 ten sample test runs):( [0]: https://www.cdc.gov/niosh/npptl/respirators/testing/NonNIOSHresults.html https://www.cdc.gov/niosh/npptl/respirators/testing/NonNIOSH...
- loosescrews 5y ago
  I 100% agree that the conversation should shift to how we can get more particulate masks into people's hands. That said, N95 masks are not the gold standard many people claim they are. N99 and P100 masks typically include a gasket which improves the seal dramatically. They also come with the bonus of filtering substantially more fine particles. Given than the size of the aerosols in question are less than 5 microns and that the ratings are in relation to 0.1 microns, getting a higher rating is probably a good idea. Even better still is a silicone mask which is trivial to leak test by covering the filter cartridge inlets (negative pressure) or exhaust valve (positive pressure).
- disabled 5y ago
  PAPRs (powered air purifiying respirators) would be far more effective and efficient, especially on a long-term basis. People who are at risk of becoming severely ill from a respiratory infection (i.e. Pneumovax 23 recipients), especially in the developed world, should be able to have their national/public/private health insurance pay for a PAPR. After the pandemic, this really should be the case. There are also more compact, more convenient, and better designed PAPRs coming out, such as the Optrel Swiss Air [1] and the CleanSpace Halo [2]. Most PAPRs do not require fit tests to ensure the seal, while N95/N99/P100 masks do. The PAPRs I list can easily be adapted, either formally or informally, to have source control (covering of the exhaust valves). [1] Optrel Swiss Air: https://industrial.optrel.com/fileadmin/optrel/redaktion/pdf/en/productflyers/swiss-air-folder4S-en.pdf https://industrial.optrel.com/fileadmin/optrel/redaktion/pdf... [2] CleanSpace Halo: https://cleanspacetechnology.com/wp-content/uploads/2019/11/2-CleanSpace-Halo-Training-Notes_June2018-V1.pdf https://cleanspacetechnology.com/wp-content/uploads/2019/11/...
- dehrmann 5y ago
  I'm curious why there hasn't been a push for this.
- Tepix 5y ago
  There has been a large push for N95 masks in Germany. They are now mandatory when doing grocery shopping. You're allowed to use a "surgical mask" instead, however. I think those offer few less protection to the wearer.
TheRealSteel 5y ago
This is untrue. There is an overwhelming amount of evidence that masks reduce the spread of Covid.
- __blockcipher__ 5y ago
  The only RCT ever performed for self infection of SARS-2 in the community failed to reach significance. No RCT of community masking for SARS-2 transmission has ever been done, probably because it’s unfeasible (translation: we’ve constructed an unfalsifiable hypothesis). Can you point me to a non mechanistic non associative study that demonstrates that face masks work to prevent community transmission of SARS-2? EDIR: I can’t reply to the child comment about condoms (does HN have a nesting limit?) but suffice to say we only have 1 RCT on SARS-2 so playing the significance game is silly. You can’t point to a single RCT showing an effect because it doesn’t exist. That’s the problem. We’re mandating an intervention that is unproven to work and rests on theoretical assumptions that are now known to be false. You can go look at non-SARS-2 RCTs if you want but those also look abysmal. For example go read Macintyre’s cluster-randomized controlled trial of cloth masks in healthcare workers. It’s not encouraging.
  - sampo 5y ago
    > The only RCT ever performed for self infection of SARS-2 in the community failed to reach significance. Do condoms work against sexually transmitted diseases? 5 out of 10 RCT studies reported statistically significant effect. Do condoms work against unwanted pregnancy? 0 out of 4 RCT studies reported statistically significant effect. https://jech.bmj.com/content/65/2/100 https://jech.bmj.com/content/65/2/100
    - __blockcipher__ 5y ago
      Wow, what an intellectually dishonest description of your citation. It’s looking at interventions to promote condom usage, not condom usage. Forgive my tone but...just wow.
      - 5y ago
dxdm 5y ago
Dear internet stranger, do you have any credible citations to back up your claims about the effectiveness of masks?
- __blockcipher__ 5y ago
  https://www.acpjournals.org/doi/10.7326/m20-6817 https://www.acpjournals.org/doi/10.7326/m20-6817 - Only community RCT of masking for SARS-2 ever performed. Failed to reach significance, bounds are from (in plain english) “slight-moderate worsening” to “moderate+ improvement” in transmission. Endpoint was self infection not source control. No RCT of source control for SARS-2 exists, and yet everyone in this thread besides me is advocating for usage of this unproven intervention, how curious. https://bmjopen.bmj.com/content/5/4/e006577?fbclid=IwAR1eSycUvJj_dy8CeGpVOkLzT53HJhr7HWv2VYj9bVXxdVedx167Y8te2Y0 https://bmjopen.bmj.com/content/5/4/e006577?fbclid=IwAR1eSyc... - cluster-randomized controlled trial of masking in hcw. Compared cloth masking to “standard practice”, not a no-mask control, but results caution against usage of cloth masks due to abysmal filtration efficiency and the increased infections in the group relative to standard practice I’d have to cite like 10 different studies to show the full story on aerosol transmission and I’m on mobile so I’ll leave that as an exercise to the reader for now. But I’d like someone to at least answer this: If you take it as fact that SARS-2 primarily spreads through aerosols, what does that imply about the efficacy of masking for source control of SARS-2? There is a reason that the health authorities advocating community usage of masks (which they never did for any respiratory pathogen pre-COVID btw) maintain that SARS-2 spreads through large respiratory droplets. It’s because otherwise the whole concept of community masking is absurd.
  - amanaplanacanal 5y ago
    > If you take it as fact that SARS-2 primarily spreads through aerosols Is that actually a fact though?
    - __blockcipher__ 5y ago
      I think a review of the relevant literature shows that it quite obviously is, but I’m about to go to sleep and don’t want to fight that battle thus why I’m trying to direct your attention to the actual point. So let’s try again: If you take it as a given that SARS-2 primarily spreads via aerosols, what does that imply about the efficacy of strapping a warm, damp piece of cloth over your breathing holes?
jtsiskin 5y ago
That’s study says “Immunity elicited by direct vaccination or by maternal vaccination prolongs host survival but does not prevent infection, viral replication or transmission, thus extending the infectious periods of strains otherwise too lethal to persist.” Is this your concern with the covid vaccine? That a strain which would have killed someone unvaccinated, that person will now instead stay alive and spread it? The viruses used and discussed in that study had between a 60% and 100% fatality rate. This is pretty different than covid 19
- __blockcipher__ 5y ago
  Right but imagine the same study but performed on 1 billion people for a much less lethal virus. That’s what we’re doing with this mass global vaccination campaign. So yes, that is my concern. But I mainly mention it because it’s a handy counter to the utilitarian collectivist argumentation without having to argue against the ethics of collectivism itself.
Emphere 5y ago
What are the obvious negative of face masks?
- __blockcipher__ 5y ago
  Worsening acne vulgaris Worsening rosacea Difficulty communicating with the hard of hearing, language learners, etc Reduced ability to convey info via facial expressions Altered risk appraisal Having to stand closer or speak louder to convo partner Psychological discomfort Bacterial pneumonia Cross-contamination (hand to mask, mask to hand, hand to face) Mild negatives from uncomfortable pressure on ears Sends a message of societal fear that there is something to be afraid of (you might consider this a positive, I don’t personally) Encourages viewing the wearer as just a vector for disease Increased CO2 buildup
  - Emphere 5y ago
    Your logic is flawed because additive risks like that cannot be compared to exponential risks (like the spread of a virus). There's an asymmetry in the outcomes and the potential upside is enormous; especially when your stated risks are minimal to (say the least), like acne or in some cases, have been proven to be wrong by data (re: psychological "discomfort"--suicide rates decreased last year).
    - __blockcipher__ 5y ago
      Suicide rates are not the same thing as discomfort. Calling the risks minimal to acne makes no sense. It’s one of the worst contributors to acne in any person’s daily life. Even if I agreed with your exponentiality argument the whole point is that I’m saying masks don’t reduce spread. You seem to think there’s only possible upside, but there is equally downside wrt xmission; that is, masks run the risk of worsening transmission.
      - Emphere 5y ago
        Yes, but they are a pretty good proxy for psychological discomfort levels/rates. And my point was that you can't really compare acne to covid as the latter is much worse (let me emphasize that you _don't_ have to agree with me on this, all you need to agree with is the fact that exponential risk >>>>>>> additive). Furthermore, there is nothing to suggest that masks run the risk of worsening transmission. I see from your other comments that you're familiar with the mask clinical trials (presumably you're referring to the Danish study). That study was inconclusive (also note that it was _severely_ underpowered), and considering that _nothing_ in our previous knowledge suggests that they worsen infection rates, your reasoning is once again flawed.

sterlind 5y ago

we should be pushing for N95 masks to be cheaper and more available. those masks block aerosols when they're properly fitted (and we should make them easier to fit.)

__blockcipher__ 5y ago
I would love for N95 usage to become more widespread, but that is hampered by the dogmatic clinging to the belief that cloth masks actually work, unfortunately. Do N95s work for source control though? They certainly do work for self infection but I haven’t personally read any N95 studies on source control so am not sure.
- sterlind 5y ago
  the ones without exhalation valves do. the barrier is bidirectional. the ones with valves bypass this which is why those shouldn't be used for source control but are popular for wildfires etc.
  - __blockcipher__ 5y ago
    Thanks. That was my thinking but glad to see it confirmed. Kind of ironic that you’re not allowed to wear an N95 with an exhale valve, but are encouraged to wear a surgical mask, bandana, cloth mask, or dirty T-shirt, none of which provide any source control. Again, the elephant in the room is respiratory viruses in general, and SARS-2 in particular, spread via aerosols. Non-N95 face coverings cannot block aerosols. Indeed mask wearing leads to deeper breaths to maintain homeostasis (this has been studied), therefore lead to a greater net volume of air, therefore lead to increased aerosol emission before even accounting for the potential to nebulize large droplets into a shower of tiny aerosol particles. But I digress.
    - loosescrews 5y ago
      A surgical mask, bandana, cloth mask, or dirty T-shirt over a particulate mask (e.g. N95) is typically allowed. There are serious benefits to the wearer to having an exhaust valve. Wearing a second, less effective face covering over the particulate mask retains the benefits of the particulate mask and exhaust valve while maintaining the same level of source control as without the particulate mask.
- arrrg 5y ago
  Where are you from that FFP2 usage is not common? Sure, cloth masks were widespread for about a year but by now usage of FFP2 masks is becoming extremely widespread, especially since the supply is by now overwhelming.
nyokodo 5y ago
> and we should make them easier to fit Not to mention make versions for unusual face sizes (big and small). I cannot find one large enough for my face.
- Tor3 5y ago
  And my wife can't find ones small enough to fit her face properly. In her home country masks come in all sizes and shapes, in Europe there seems to be only a single size. At least every type I've looked at is the same size as all the others.
- godelmachine 5y ago
  3M N95 9210 should be big enough to cover anyone's face, methinks.
  - Semaphor 5y ago
    They are also pretty expensive for a single-use product.
    - godelmachine 5y ago
      They are but I believe to will protect anyone extremely well.
- Semaphor 5y ago
  I found one with an amazing fit from China that was large enough. Then I googled the name and found out it’s listed under the fake/mislabeled category on the CDC site [0] with filtration efficiency between 8 and 94% (over 2 ten sample test runs):( [0]: https://www.cdc.gov/niosh/npptl/respirators/testing/NonNIOSHresults.html https://www.cdc.gov/niosh/npptl/respirators/testing/NonNIOSH...
loosescrews 5y ago
I 100% agree that the conversation should shift to how we can get more particulate masks into people's hands. That said, N95 masks are not the gold standard many people claim they are. N99 and P100 masks typically include a gasket which improves the seal dramatically. They also come with the bonus of filtering substantially more fine particles. Given than the size of the aerosols in question are less than 5 microns and that the ratings are in relation to 0.1 microns, getting a higher rating is probably a good idea. Even better still is a silicone mask which is trivial to leak test by covering the filter cartridge inlets (negative pressure) or exhaust valve (positive pressure).
disabled 5y ago
PAPRs (powered air purifiying respirators) would be far more effective and efficient, especially on a long-term basis. People who are at risk of becoming severely ill from a respiratory infection (i.e. Pneumovax 23 recipients), especially in the developed world, should be able to have their national/public/private health insurance pay for a PAPR. After the pandemic, this really should be the case. There are also more compact, more convenient, and better designed PAPRs coming out, such as the Optrel Swiss Air [1] and the CleanSpace Halo [2]. Most PAPRs do not require fit tests to ensure the seal, while N95/N99/P100 masks do. The PAPRs I list can easily be adapted, either formally or informally, to have source control (covering of the exhaust valves). [1] Optrel Swiss Air: https://industrial.optrel.com/fileadmin/optrel/redaktion/pdf/en/productflyers/swiss-air-folder4S-en.pdf https://industrial.optrel.com/fileadmin/optrel/redaktion/pdf... [2] CleanSpace Halo: https://cleanspacetechnology.com/wp-content/uploads/2019/11/2-CleanSpace-Halo-Training-Notes_June2018-V1.pdf https://cleanspacetechnology.com/wp-content/uploads/2019/11/...
dehrmann 5y ago
I'm curious why there hasn't been a push for this.
Tepix 5y ago
There has been a large push for N95 masks in Germany. They are now mandatory when doing grocery shopping. You're allowed to use a "surgical mask" instead, however. I think those offer few less protection to the wearer.

TheRealSteel 5y ago

This is untrue. There is an overwhelming amount of evidence that masks reduce the spread of Covid.

__blockcipher__ 5y ago
The only RCT ever performed for self infection of SARS-2 in the community failed to reach significance. No RCT of community masking for SARS-2 transmission has ever been done, probably because it’s unfeasible (translation: we’ve constructed an unfalsifiable hypothesis). Can you point me to a non mechanistic non associative study that demonstrates that face masks work to prevent community transmission of SARS-2? EDIR: I can’t reply to the child comment about condoms (does HN have a nesting limit?) but suffice to say we only have 1 RCT on SARS-2 so playing the significance game is silly. You can’t point to a single RCT showing an effect because it doesn’t exist. That’s the problem. We’re mandating an intervention that is unproven to work and rests on theoretical assumptions that are now known to be false. You can go look at non-SARS-2 RCTs if you want but those also look abysmal. For example go read Macintyre’s cluster-randomized controlled trial of cloth masks in healthcare workers. It’s not encouraging.
- sampo 5y ago
  > The only RCT ever performed for self infection of SARS-2 in the community failed to reach significance. Do condoms work against sexually transmitted diseases? 5 out of 10 RCT studies reported statistically significant effect. Do condoms work against unwanted pregnancy? 0 out of 4 RCT studies reported statistically significant effect. https://jech.bmj.com/content/65/2/100 https://jech.bmj.com/content/65/2/100
  - __blockcipher__ 5y ago
    Wow, what an intellectually dishonest description of your citation. It’s looking at interventions to promote condom usage, not condom usage. Forgive my tone but...just wow.
    - 5y ago

dxdm 5y ago

Dear internet stranger, do you have any credible citations to back up your claims about the effectiveness of masks?

__blockcipher__ 5y ago
https://www.acpjournals.org/doi/10.7326/m20-6817 https://www.acpjournals.org/doi/10.7326/m20-6817 - Only community RCT of masking for SARS-2 ever performed. Failed to reach significance, bounds are from (in plain english) “slight-moderate worsening” to “moderate+ improvement” in transmission. Endpoint was self infection not source control. No RCT of source control for SARS-2 exists, and yet everyone in this thread besides me is advocating for usage of this unproven intervention, how curious. https://bmjopen.bmj.com/content/5/4/e006577?fbclid=IwAR1eSycUvJj_dy8CeGpVOkLzT53HJhr7HWv2VYj9bVXxdVedx167Y8te2Y0 https://bmjopen.bmj.com/content/5/4/e006577?fbclid=IwAR1eSyc... - cluster-randomized controlled trial of masking in hcw. Compared cloth masking to “standard practice”, not a no-mask control, but results caution against usage of cloth masks due to abysmal filtration efficiency and the increased infections in the group relative to standard practice I’d have to cite like 10 different studies to show the full story on aerosol transmission and I’m on mobile so I’ll leave that as an exercise to the reader for now. But I’d like someone to at least answer this: If you take it as fact that SARS-2 primarily spreads through aerosols, what does that imply about the efficacy of masking for source control of SARS-2? There is a reason that the health authorities advocating community usage of masks (which they never did for any respiratory pathogen pre-COVID btw) maintain that SARS-2 spreads through large respiratory droplets. It’s because otherwise the whole concept of community masking is absurd.
- amanaplanacanal 5y ago
  > If you take it as fact that SARS-2 primarily spreads through aerosols Is that actually a fact though?
  - __blockcipher__ 5y ago
    I think a review of the relevant literature shows that it quite obviously is, but I’m about to go to sleep and don’t want to fight that battle thus why I’m trying to direct your attention to the actual point. So let’s try again: If you take it as a given that SARS-2 primarily spreads via aerosols, what does that imply about the efficacy of strapping a warm, damp piece of cloth over your breathing holes?

jtsiskin 5y ago

That’s study says “Immunity elicited by direct vaccination or by maternal vaccination prolongs host survival but does not prevent infection, viral replication or transmission, thus extending the infectious periods of strains otherwise too lethal to persist.” Is this your concern with the covid vaccine? That a strain which would have killed someone unvaccinated, that person will now instead stay alive and spread it? The viruses used and discussed in that study had between a 60% and 100% fatality rate. This is pretty different than covid 19

__blockcipher__ 5y ago
Right but imagine the same study but performed on 1 billion people for a much less lethal virus. That’s what we’re doing with this mass global vaccination campaign. So yes, that is my concern. But I mainly mention it because it’s a handy counter to the utilitarian collectivist argumentation without having to argue against the ethics of collectivism itself.

Emphere 5y ago

What are the obvious negative of face masks?

__blockcipher__ 5y ago
Worsening acne vulgaris Worsening rosacea Difficulty communicating with the hard of hearing, language learners, etc Reduced ability to convey info via facial expressions Altered risk appraisal Having to stand closer or speak louder to convo partner Psychological discomfort Bacterial pneumonia Cross-contamination (hand to mask, mask to hand, hand to face) Mild negatives from uncomfortable pressure on ears Sends a message of societal fear that there is something to be afraid of (you might consider this a positive, I don’t personally) Encourages viewing the wearer as just a vector for disease Increased CO2 buildup
- Emphere 5y ago
  Your logic is flawed because additive risks like that cannot be compared to exponential risks (like the spread of a virus). There's an asymmetry in the outcomes and the potential upside is enormous; especially when your stated risks are minimal to (say the least), like acne or in some cases, have been proven to be wrong by data (re: psychological "discomfort"--suicide rates decreased last year).
  - __blockcipher__ 5y ago
    Suicide rates are not the same thing as discomfort. Calling the risks minimal to acne makes no sense. It’s one of the worst contributors to acne in any person’s daily life. Even if I agreed with your exponentiality argument the whole point is that I’m saying masks don’t reduce spread. You seem to think there’s only possible upside, but there is equally downside wrt xmission; that is, masks run the risk of worsening transmission.
    - Emphere 5y ago
      Yes, but they are a pretty good proxy for psychological discomfort levels/rates. And my point was that you can't really compare acne to covid as the latter is much worse (let me emphasize that you _don't_ have to agree with me on this, all you need to agree with is the fact that exponential risk >>>>>>> additive). Furthermore, there is nothing to suggest that masks run the risk of worsening transmission. I see from your other comments that you're familiar with the mask clinical trials (presumably you're referring to the Danish study). That study was inconclusive (also note that it was _severely_ underpowered), and considering that _nothing_ in our previous knowledge suggests that they worsen infection rates, your reasoning is once again flawed.