[mech1234]

You are claiming that the masks are useless. They are not. They have some effectiveness, and that effectiveness is limited. This is well-understood. Aerosol-based transmission is well-understood. Claiming that there are "gotchas" does not change the fact that wearing a mask reduces your risk.

You are doing the very thing that I pointed out as incorrect: removing nuance.

A more honest expression of your position would be "the limited effectiveness of the masks and their limited supply means that it is reasonable for the masks to be reserved for those who need them most." The honest debate around this position regards how much supply there is, how much individual liberty should dictate demand, and other such factors. The latter half of your post comes around to this, even though the first half is incorrect.

[baddox]

I thought the nuanced explanation is something more like "technically it's possible that a bit of material in front of your face could stop a droplet carrying a pathogen, but unless used as intended (which generally requires training) the masks are largely ineffective and you'll actually be less safe if you inaccurately estimate your risk due to thinking that a mask is an effective preventative device for you."

In other words, it's actually unnuanced for you to say "the masks are not useless." It must also be technically possible for a wide-brimmed hat to happen to block a pathogen-carrying droplet and prevent you from inhaling it. It's probably even possible that wearing a magnet around your neck could just ever-so-slightly nudge a single droplet and cause it to not enter your mouth or nose.

[achenatx]

there isnt much training required. I worked in a BSL 3 lab with aerosolized tuberculosis and the training was like 5 minutes.

Even if you touch the mask with your hands and it is contaminated, if you wash your hands after taking the mask off you will be fine.

The "you need training" is part of the media agenda.

I agree that statistically masks wont stop the virus from spreading in the public. While masks used by health care workers will stop the virus from spreading to health care workers. The reason is that most of the public wont use masks while all health care workers will.

[baddox]

I could have left out the training part of my comment because it's not important to my argument (although my guess is that you'd be very surprised how many people who wear these masks in public use them extremely cavalierly and improperly).

The rest of my argument stands if you drop the part about training.

[sgc]

It's not like there are week long courses on how to wear a mask. Most anybody watching a youtube video or two could wear a mask mostly correctly, so that it would mostly do what it is intended to do. Nothing is perfect, but the goal is risk reduction anyways. The correct response to the problem of improper mask use is give people the little bit of information they need and strongly encourage them to use that information, not fall into despair or indifference. I have a P100 mask with manufacturer published pandemic sterilization procedures for work[1]. It's not expensive and it's not hard.

And yes of course medical professionals need them before everyone else, but being shamed for taking basic precautions during a pandemic is just embarrassing for society.

[1] https://www.srsafety.com/us/products/pandemic-flu-kit-sr-100...

[jbob2000]

I don't disagree with you, but the risk reduction they provide is so little that you may as well call them "useless".

You should go buy a lotto ticket! There's a chance you could win!

[aeternum]

Masks provide extreme risk reduction for others if the wearer has the virus. Combine that with the 2-week incubation period and masks are quite effective.

Mask wearing was a law in SF during the 1918 epidemic and saved many lives. Once again, history is forgotten.

[achenatx]

the risk reduction is actually very high. But the probability of being in the presence of the virus is very low. Health care workers treating infected patients have a 100% chance of being exposed so epidemiological risk reduction is large.

I think the "useless" part actually refers to the the fact that the public at large wont be wearing masks so a few people wearing masks might protect themselves, but does nothing to alleviate the overall spread of the virus.

[PeterisP]

The probability for being in the presence of the virus is very low right now in USA, but it's quite high in many other places (e.g. Iran) right now and in USA in the near future.

If media can be pushed to destigmatize wearing of masks and stigmatize not wearing of masks, then this (combined with starting manufacturing large quantities of masks) would alleviate the overall spread of the virus in the post-containment mitigation phase, in which many countries are right now.

[JoeAltmaier]

I understand that wearing a mask doesn't prevent the wearer (for most common masks) but instead protects other people. Should you be a carrier. It slows the spread, which is a good thing?

[kps]

It's a matter of terminology; ‘mask’ has a narrower meaning than in colloquial use. https://www.cdc.gov/niosh/npptl/pdfs/UnderstandDifferenceInf...

(Compounding the confusion is that a reusable rubber respirator is also called a ‘half mask’.)

[mhb]

What is your basis for this? My understanding is that an N95 mask, worn by following the directions on the box, provides significant protection to the wearer. Also, if it has a vent for exhaling, that would suggest it is not necessarily such good protection for others.

[mech1234]

In matters of life and death, being careful is important. Taleb and others have a lot to say about tail risk, and coronavirus looks like a large tail risk to me. If I were a resident or planned an urgent visit in a Seattle nursing home I'd spend a good bit of money on PPE.

The lottery ticket analogy does not work well. I'm reminded instead of the scenes in the Chernobyl mini-series where individuals are sent into unknown dangers- dangers that are impossible to see, difficult to understand, and require conscious thought and effort to avoid. Resources are scarce and authority figures do not have sufficient information to keep everyone as safe as they should. Whether you survive or not comes down to both luck (whether your place and duties precluded you from any other option) and ignorance (whether you picked up a chunk of radioactive graphite with your bare hand). Using PPE is an effort to counteract your ignorance.