>>"Recent case in point: public health authorities telling the public that masks are useless and even harmful during the pandemic (presumably to avoid shortages) and then reversing their stance when masks became abundant."

I agree with your general point, but my interpretation of those events has additional axis:

1. Masks are in shortage, and may not protect you, and public doesn't know how to use them and will probably do more harm than help by reusing and handling and touching their masks

Then as time passed and we learned more

2. This is getting bad; even if masks don't save the person wearing them, if it helps others, we are at a point where we need all the help we can get. Please wear masks to help slow the overall spread.

While there's definitely part of the complex factoring of the recommendation that masks became more abundant, I feel initial message was "Crappy masks won't save you" and later message "Crappy masks won't save you, but may save others from yourself"

98% of people I talk to don't understand that surgical mask / cloth mask will do extremely poor job of protecting them; but may protect others. (it also adds an axis of complexity for those who don't want to wear masks because they feel they have the right not to protect themselves, because that's not what mainstream masks are for; it's not about wearing a helmet or not to protect your own head; it's about protecting heads of those around you)

> 98% of people I talk to don't understand that surgical mask / cloth mask will do extremely poor job of protecting them

This was the line for a while, but since we now know that it's an airborne infection that basically accumulates when you're in close proximity to someone infected until it reaches a critical point where it can grow faster than your body can fight it off, the mask is the only thing that's slowing it down.

Masks (and good ventilation) are about the only thing that protects you - social distancing means nothing because coronavirus isn't confined to the larger droplets we thought it was. Mask-wearing seems to result in less-serious infections even when you catch it because your initial infection was likely by less virus.

edit: I think there was an official reluctance to admit that it was completely airborne because the constant attempts to reopen businesses (like restaurants) would have been completely thwarted if social distancing (and constant surface sterilization) were meaningless.

And then, when they finally got around to actually applying some science to the question, the message became, "Surgical and (decent) cloth masks will protect others from yourself, and may also protect you."

I can't track down papers atm, but, on a more anecdotal level, there have been quite a few case studies of superspreader events where the people who were wearing masks were much less likely to contract the illness than people who weren't. Given the specific details at play, it's hard to explain how that could happen if cloth or surgical masks don't protect oneself as well.

The big problem here was that, early on, nobody knew exactly how the virus spread. So, in the interest of caution, they picked the worst case scenario, aerosol transmission, and speculated based on that assumption. And a cloth or surgical mask probably won't protect the wearer very well in that case. But it turns out that droplet transmission seems to be the better model.

> The big problem here was that, early on, nobody knew exactly how the virus spread. So, in the interest of caution, they picked the worst case scenario, aerosol transmission, and speculated based on that assumption. And a cloth or surgical mask probably won't protect the wearer very well in that case. But it turns out that droplet transmission seems to be the better model.

So close but so far.

At a minimum please give https://www.thelancet.com/journals/lancet/article/PIIS0140-6... a read. The real story is that SARS-2 does spread through aerosols whereas droplet transmission is pure unproven dogma. The paper I linked goes into some reasons why that is the case (for ex the fact that transmission is more likely close to someone doesn’t actually provide strong evidence for droplet xmission)

EDIT: I should add that even if it were primarily droplet transmission - which I very much doubt - masking would likely still fail for the stated goal (source control) in a community setting due to improper usage. And improper usage doesn't just mean "the mask is below your nose", it means "you're not changing out the mask the moment it gets damp", "you're touching your mask with unwashed hands", "you're touching your hands with unwashed mask", "you're standing closer to your conversational partner to compensate for the fact that masks muffle hearing" (<--this last one isn't "improper usage" so much as an inevitable result but I digress). And this is all without discussing any of the various negatives of mask-wearing that it's become trendy to pretend literally don't exist.

But to your point, you already correctly hinted at the fact that if aerosol transmission is the dominant transmission mode, then masks don't work even in theory, let alone in practice.

The problem is they lost all credibility with the public for that very obvious deception.

Which deception? I did not indicate one in my post so reference to " that very obvious deception" is not clear to me.

note: "Evolving understanding/new facts" or "new/differing priorities" are not the same as "deception" to me. e.g.:

* Thinking A and Saying A; then changing mind and Thinking B and Saying B; are not a deception

* Saying "Because of X, A"; then later "Because of Y, B", because Y became more important than X, is also not deception to me

* Thinking A but Saying B is a deception to me (for reasons and intents that I may or may not agree with)

I'm with you. To me, it was pretty clear why they were making recommendations in the way that they did. There was no secret about why they wanted to limit the supply of masks going to the public at the start of the pandemic. They didn't know for sure how it spread, but they did know that the most important places to have masks were the hospitals. You need to be extraordinarily cautious there because every hospital worker that gets sick reduces the number of people available to deal with patients (and adds another patient). There was also concern about face touching if people not used to masks started wearing them, but I only recall seeing that being a concern when it came to sending children to school with masks.

Once the mask supply was able to meet demand and after they were reasonably certain it would protect against the spread of the virus, they adjusted their recommendations accordingly.

None of that is deceptive.

That's sarcasm but let me try to address the notion behind it, to best of my limited personal understanding; "prevent spread" has multiple factors to it.

My impression, in my locality, is that at beginning of pandemic people focused on notion of using masks to protect themselves (and many though not all governments indicated that's not efficient/recommended).

Then "as time passed and we learned more" focus moved to using masks to protect others (though many individuals, in my circle, still aren't clear on that).

My impression is that we have evolving, and still not necessarily 100% certain evidence/understanding, on how it spreads and what are the most effective measures. It's made more complex because

a) there's no silver bullet; most measures increase your chances to some percentage. This makes discussion between experts and public more difficult as public tends to think in binary terms.

b) While yes there are many public health measures we've known for 100 years (wash hands, have clean water, cook/boil/heat things to sterilize them, sneeze in elbow/Kleenex, wear mask, remove waste, etc etc), not all are equally effective against all vectors. What seems "Common sense" / "Logical" to a layperson like myself, may be more nuanced to an expert with experience.

I mean, for what it's worth, I'm 100% certain my dad, a year in, is still worse off for using a mask because of how he uses it. Many and especially older people around me reuse their masks for days and weeks , touch them constantly, put them under their nose for prolonged periods, don't squeeze/tighten them sufficiently, etc. Even if all that touching doesn't hurt, their belief that they're protected coupled with incorrect usage coupled with likely increase in risky behaviour is a net negative.

People can scream liberty and freedoms and personal responsibility, but I feel public health officials have to look at cold hard facts, of both disease but also people's actual behaviour (as opposed to some ideal non-existent form) and how it actually affects spread rather than how it logically intuitively should.

My impression is that importance of mask is well-studied and masks are regarded as one of the most important hygienic achievements right behind washing hands. These are cold hard facts. Everything else is political wiggle-waggling.

You may argue whether it is okay for a technocratic establishment to lie to people and manipulate them; but to pretend that they didn’t feed the public with half-truths is just ridiculous.

I think we have wildly different understanding; and mine is very much evolving - as I feel is everybody else's.

Masks right behind washing hands - honestly, until Covid, I clearly lived in ignorance and had NO idea that a) Surgical masks are tested and designed to protect others against exhale and b) N95 masks are tested and designed to protect occupant via inhale. Just that basic, yet absolutely crucial concept was unknown to me. I had very limited exposure to them across two continents and half a dozen countries, and it certainly wasn't part of my own education about most important hygienic achievement or practice across four different educational / political / health systems. That doesn't necessarily mean masks aren't crucial, but it perhaps doesn't make it obviously so either in context of daily public health.

And then we have the mucky complex detail of aerosol vs droplet vs surface, sizing and staying power, etc.

You are presenting / clearly strongly believe that (all?) masks are a binary, always-good, always-clearly-protective thing.

My understanding/interpretation is that it's more complex than that; I am OK with scientists, when faced with a net new illness, inherently evolving the opinion and recommendations. I guess this is where you see a "technocractic establishment lying and manipulating". I look at wildly different countries with wildly different values, framework, goals, assumptions, methods, and yes "political wiggle-waggling", and most of those culturally politically different scientists following broadly similar path of learning and understanding.

It is likely our frameworks and life paradigms are too different to come to an agreement - at some point we all, you and I included, fit inbound facts and perceptions into our root approach and beliefs.

I think OP meant the general public's familiarity with using masks day to day. I think Japan has had the jump on the US for some time in that regard.