[nnq]

Masks ALWAY help, a little or more, in one way or other. Any masks. Period. If you have them or you can get them easily, use them!

They help because:

1. you have a significant chance of being already infected with a mild form and contagious even if you don't know it - wear a damn mask to protect the really vulnerable people around from your viruses!

2. any masks reduces even by a tiny amount the chance of infection - you eat more veggie fibers to reduce your chance of colon cancer by a single digit percent ...wear a goddam mask to reduce even if by very little the risk of catching (and then spreading) COVID-19!

3. by wearing a mask you'll be imitated by a few others and make it socially more acceptable for others to wear too - some of the people who end up wearing makes because of you are probably already infected and don't know it, so you'll have limited spread by promoting the "fashion"! (also, a few are probably immunodepressed or otherwise sensitive and might not even know it so simply copying a "fashion" could save their lives)

PLEASE, wear a mask, any masks, even wear it badly, but do! Do it for others and to slow the spread of disease worldwide enough to allow healthcare systems to have a chance of coping with it, and to give vulnerable or unlucky people developing the rare severe cases a decent chance of survival!

And wash your hands!

(Yeah, 50-70% of the human population will get this, eventually. But it's incredibly stupid if we get it all at fucking once! Unless you're shorting some stocks or pursuing a dubious political agenda, you don't want this to happen.)

EDIT+: ...but don't go the other extreme, buying them at exorbitant prices despite being healthy and not at high risk, or hoarding them.

[yellowstuff]

I read something saying that people with masks had been observed to take them off to eat, put them down on a dirty table, and then put them back on their face. So you should add the caveat that properly used masks always help, all else equal.

[nnq]

Using a mask like you described still helps significantly. (Would help 10x more if the user would put it in a damn plastic bag, not on the table!). If you wear the mask on crowded bus or subway and take it off when you enter a not-so-crowded-and-frequented caffe you still did a lot!

What would help a lot would be smth. like a high-power-UV portable box that could fit in a backpack (or a chemical equivalent), to allow at least some imperfect but useful re-sterilizing of masks... single-use N95s are hugely wasteful...

I think our current focus on "perfect" and "100% correct" (whatever that even means...) hurts managing pandemics A TON! An approach where we'd recognize the probabilistic nature of contagion and fight for +1% probability of desired-event-X1, -0.1% prob. of undesired-event-X2 etc. would be much useful... at whole-population scales all measures will be sloppily implemented in practice and we need to accept than and just "tweak the odds" until "we're mostly winning"...

(For sure, use better proven and standardized methods in hospitals and other settings with well trained people paid to implement measures correctly. But don't expect most of the average population to bother doing things the optimal way even when they've been educated about it... there's opportunity costs to everything, even to "giving a f"!)

[stubish]

Putting a mask on a dirty table and putting it back on again does not render using the mask completely useless. It just lowers the risk reduction a bit.