[titzer]

> but they do reduce the viral load by 30-50%

I think the effect is much larger than that, but yes, absolutely. This is an important point that is constantly lost in the public discourse. We realize there's a big difference in dosage with poisons and radiation, but it's the same with viral infections; viruses do take time to replicate, so having a low initial exposure can give the immune system to ramp up sooner, before the infection has become severe (and then the immune response will also be severe).

[timr]

All current evidence is that masks have a minor effect, measured in tiny fractions of a percent.

https://vinayprasadmdmph.substack.com/p/do-masks-reduce-risk...

To date, I'm aware of no study that has quantified a difference in infection, hospitalization or death that is attributable to travel bans.

[fragmede]

Here's a link to a real actual science study that used tuberculosis-sized particles and found filtration efficiencies of 99.5% or higher by N95 masks. Which isn't minor. It's been over a year. If you're not using an N95, you're doing yourself and those around you a disservice.

https://pubmed.ncbi.nlm.nih.gov/9487666/

[timr]

That's nice, but filtration efficiency =/= real-world efficiency. Unless you plan on super-glueing mask fabric to everyone's face holes, of course.

Also, last time I checked, most people aren't wearing N95 masks. Probably because they're annoying and difficult to wear.

> Which isn't minor. It's been over a year. If you're not using an N95, you're doing yourself and those around you a disservice.

I am vaccinated. Which brings up an important point: there is absolutely no evidence that a mask of any sort provides any benefit to those around me, a vaccinated person.

At some point, you have to put up evidence for your increasingly implausible claims -- you can't just keep leaning on lab studies of filtration efficiency. It's been two years now. Where is the real-world data backing your claims?

[Terretta]

Feels like you’re slinging a lot of assertions without substantive evidence, seemingly asking people to “Google that for you”.

Among other things, vaccinated persons can and do contract, carry, and spread, during which a decent* mask does do its thing.

And who doesn’t wear an N95 class mask? I see about 2/3rds N95, KN95, or KF94s, 1/3 useless masks, appearing to be mostly correlated along economic lines ($2/masks vs. $0.50/masks).

PS. This is bigger than “fractions of a percent”:

https://jdrampage.org/real-world-covid-mask-trial-proves-mas...

* This shows lame mask are lame:

https://pubmed.ncbi.nlm.nih.gov/32512240/

Put those two concepts together, you get humdinger models suggesting:

“… if only around half of the population opted to wear respirator-type masks from the beginning of the pandemic, COVID-19 would have failed to establish in the United States.”

https://royalsocietypublishing.org/doi/10.1098/rsos.210699

(Would have needed closer to 2/3 with those sneeze guard ’surgical’ masks.)

[Wowfunhappy]

> And who doesn’t wear an N95 class mask? I see about 2/3rds N95, KN95, or KF94s, 1/3 useless masks, appearing to be mostly correlated along economic lines ($2/masks vs. $0.50/masks).

I can't comment on the rest of the science, but fwiw, I live in NYC and I'd estimate that maybe 1 / 20 people I see on the street are wearing N95/KN95/KF94 masks. Everyone else just wears cloth masks, or paper surgical masks.

[Terretta]

Sorry, yes, you’re right, it follows that there would be areas with 1/20 as you describe.

[nradov]

None of that is relevant. The virus is now endemic so everyone will eventually be exposed regardless of whether they wear masks in some situations.

https://www.medpagetoday.com/opinion/vinay-prasad/94646

[Terretta]

It’s relevant to the point that was begin discussed.

TBC, I’d agree that your point, that of the article you shared, is valid. But it doesn’t pertain to the claims of inefficacy of masks outside a lab.

[timr]

> PS. This is bigger than “fractions of a percent”:

No, it isn't. If you'd bothered to read the content of the link I posted in the comment to which you're replying, you'd see that it's about the same paper.

That paper is mentioned numerous times in the thread you're commenting on, I've linked to it, as have others, and I've cited the absolute effect size: 0.09%.

The paper showed that there was an 11% drop on a baseline infection rate of 0.79%, in a fully unvaccinated population with very little natural immunity. It is the absolute best possible argument for masks, and it showed that cloth masks had no detectible effect, and that surgical masks had an effect size measured in tiny fractions of a percent.

[blagie]

1) There are a lot of comfortable masks which have high filtration. They're used widely in Asia. It's no >99%, but it is >90% when used reasonably. If both sides use them, that brings viral loads down by >99%, though.

2) You're right that Americans are idiots who mostly can't tell the difference between a piece of cloth, which reduces viral loads marginally, and a proper mask.

3) Vaccinations have minimal impact on spread for extended in-door socialization (~30% reduction in odds of spread at this point). They do pretty well for reducing risk to you (e.g. death or hospitalization), and they seem to do pretty well for avoiding casual spread (e.g. passing someone on the street).

[stjohnswarts]

You seem to be getting downvoted for no reason. Lot of angry people out there.

[nradov]

And so what are you suggesting? Everyone wear N95 masks all the time forever?

[NikolaNovak]

It's tricky.

- fwiw, I personally plan to wear n95 mask outside of home in enclosed public spaces for the foreseeable future, and for things like shopping etc (where I'm exposed to strangers) basically indefinitely / as long as social norms and laws will allow.

- I would like for strangers around me to wear masks. There's too much uncertainty and I don't know how to quantify and otherwise address risk from stranger e.g. In waiting / cashier line, or worse yet elevator (enforced enclosed proximity). I really see no good reason to be in an elevator with unmasked stranger.

- how long and where do we legally mandate masks? Whooeee, I'm glad I don't have to make that awful formal call! :-)

But yeah. If risk is forever, than at least some of us will use ways to mitigate the risk forever in turn. It's not binary, it's a sliding scale that's very individual. so... Yeah. Welcome to the new world! Cyberpunk dystopia future is here! :-)

[timr]

> There's too much uncertainty and I don't know how to quantify and otherwise address risk from stranger

You know what would help with this? A randomized controlled trial. This isn't tricky at all, except that we can't do the science because it has become political, because people insist that they know the answer already! And if the study shows what they don't want to see, then they censor it, bury it, downvote it into oblivion, or...write missives about how they're going to ignore it.

Also, are you vaccinated? Yes? Then the answer is almost certainly no risk at all. This much we know from ~all of the data regarding vaccines and serious illness, worldwide.

[NikolaNovak]

>>"Also, are you vaccinated? Yes? Then the answer is almost certainly no risk at all"

That is not my lay person interpretation of the currently best available data.

A vaccinated person can get infected, can get seriously ill, and can spread out to others more vulnerable. It helps, drastically, and I sure as heck got mine, but my understanding is that it does not confer individual invulnerability.

[PaulDavisThe1st]

> Also, are you vaccinated? Yes? Then the answer is almost certainly no risk at all.

As of the week before last, 28% of all hospitalizations in my state (NM) related to COVID19 involved fully vaccinated people.

[vishho]

We cannot do the science, because such a randomized test would be deeply unethical. Compare to having pregnant women smoke cigarettes to study effect on the fetus. You do this only afterwards with observational data.

Next to politization there is also public health, which is more of a management science than an emperical science. And economic concerns.

From all the data worldwide, you only reduce risk of hospitalization and death, not for spreading to your grandmother or catching it from a bypasser sneezing in your face. To act like there is no risk for the leaky vaccinated, is to actually increase your risk. Data shows that asymptomatic breakthrough infections are able to cause long-COVID. Now you did not even feel sick and gave your body and immune system rest to clear the virus. Very risky!

[collaborative]

You actually want to be exposed to the virus (after vaccination) during the summer and if possible as often as possible after a successful exposure. It's the only way forward. You can't lock it out forever, and you need to play catch up with it as it evolves or by the time you get it your immune system won't know what to do with it

[feanaro]

Forever? Why would we need to do it forever when we don't do it for any other virus?

[codezero]

Probably because we should have been, and now some of us have learned. It’s been a pleasure going two years without any upper respiratory illnesses for me. I look forward to being steadfast in that since it’s really not that hard to wear a mask, and it’s not hurting anyone else when I do so.

[feanaro]

It's nice not to have upper respiratory illnesses, but I'm not going to be wearing masks forever because of that, especially since it's not clear cut that not ever getting illnesses is a good idea. (Especially since you're bound to get infected at some point. Might as well exercise the immune system a bit.)

Now, I look forward to it being more socially acceptable to wear masks when you have an infection.

[ktkoffroth]

What happens when you eventually do catch an upper respiratory disease, and your immune system is no longer used to the challenges it presents?

[spookthesunset]

There is no end game to masking. It will be in perpetuity in some places.

[bavell]

I've never seen anyone in public with an N95 mask since the pandemic started but I've seen plenty of cloth masks, bandanas and those cheap hospital masks.

[Aulig]

Interesting, in Germany, especially Bavaria, the restrictions have switched to require FFP2 (equivalent to N95 afaik) since quite a while.

[stjohnswarts]

America loves its theater. We have a whole department of government dedicated to security theater, the TSA

[Robotbeat]

How can you not have seen any? I see the KN95 type masks all over the place in public and it’s the only kind I use any more, even for my kids.

I live in Virginia, FWIW.

[planetsprite]

I don't disagree with you on the effectiveness of masks but tuberculosis bacterial cells are far larger than coronavirons.

[tenuousemphasis]

Coronavirus itself isn't airborne, it travels in aerosolized water droplets, which are significantly larger than coronavirus itself.

[wrycoder]

But which are in the airbourne size range.

[ricardobeat]

The recent Bangladesh study with 350k people found a ~10% reduction in cases, from only 40% mask adoption.

The two-cities trial early in 2020 in Germany saw a ~20% reduction. Those are in the number of infections - the number looks low but can make a massive difference in the actual transmission rate. In the German case, after a month infections dropped close to zero.

[kyrra]

That study is flawed in many ways. And one thing to point out, if you do take the study at face value, cloth mask do virtually nothing, only surgical masks did something ( AKA the intervention group).

The study was not blind, so the intervention group (those that wore surgical masks and showed the large efficacy increase) we're paid money to be part of the group. The non-intervention groups (cloth and control) did not receive any monetary compensation.

Recording of masking was done via people observing mask wearing, which also could potentially mess with the data ( as this was not blind).

Reporting of covid symptoms was entirely based on the population manually reporting it, there was no random testing to see variances in covid.

Only around 30 to 40% of cases were actually verified via a test.

The education that came with the intervention group may have caused the older population to stop going out as much, which impacted the result.

My take is that the study proved you could pay people to mask, but it's efficacy result is dubious.

CATO has a meta analysis about mask studies that is interesting (pre print still): https://www.cato.org/working-paper/evidence-community-cloth-...

[ricardobeat]

I'm pretty sure the cloth masks debacle was settled sometime around Q1 2020, a year and a half ago. Anyone arguing about this needs to find a better hobby. They've been not recommended, or explicitly banned from airlines and other places, for a long time. They just confirmed this in a very rigorous controlled study.

> were paid money to be part of the group

That's simply not true. This is the document describing the intervention to raise mask usage: https://docs.google.com/document/d/1mgY6k5SooeMt6PIqwx-7z5LZ...

It says they tested monetary & non-monetary incentives, but if you look at the execution table, it's all "Public Reinforcement". The conclusion was that Nudges and incentives outside of the core NORM [1] intervention had no effect on mask-wearing..

> Recording of masking was done via people observing mask wearing

This is good. It means they observed the overall effect on the entire population. Some previous studies relied on self-reporting which is not as reliable.

> Only around 30 to 40% of cases were actually verified via a test.

You can't force people to take a test. But the rate of positives within the ones that agreed to collection was similar to the overall self-reported one. The study goes into this at length. There is a whole section trying out a different approach where they assign the average soropositivity to non-consenters, instead of excluding them, and that makes the results even stronger.

> The education that came with the intervention group may have caused the older population to stop going out as much, which impacted the result.

That sounds like a very random hypothesis. I can come up with another dozen of these. Maybe it rained more? Too cold? Maybe there was a soap opera on, that 60 year olds love to watch? You'd think a dozen scientists from Yale, Stanford, Berkeley, John Hopkins & others would find a way to control studies for external factors... if it was this easy to challenge results you could do it for basically every paper ever published.

The paper is available for free here: https://www.poverty-action.org/sites/default/files/publicati...

[1] no cost, offering, reinforcing, modelling

[kyrra]

Cloth Masks: I think you're wrong here? Per the CDC[0] (which all airlines seem to link to), it says:

> Cloth masks should be made with two or more layers of a breathable fabric that is tightly woven (i.e., fabrics that do not let light pass through when held up to a light source).

So cloth masks are allowed. Also, this is an issue that I agree has been settled for a while, but the media/political effort to push it has been minimal, it's always "mask up", without going into the details, which can be very important.

Intervention & Money: The doc you link just says they tried different approaches, but don't seem to details the differences with the different motivational types. It's not clear to me from what I saw that they really dived into this. And when there are any kind of rewards (ie: not blind), you will get different results in the intervention group that you were not expecting (people change behavior).

Observations of Mask Usage: I agree, this is probably the better than survey based (as from what I've seen, people self-report very differently than what they really do). This was a weak critique on my part and I would have to understand what alternatives there are that could be better.

Positivity Testing: I think my original point was moot here as well. I think the better argument here is that we do not know the change that covid had already spread in any given area prior to this test. I understand that they tried to group control and intervention groups that were near one another to try to cut down on this, but it is still a big blind spot for this study.

My other issue here is that there was no random testing done to find asymptomatic cases. This is a huge issue with this virus in general, and it makes our numbers not as good (The UK being one of the few countries that has this kind of data, but it's not truly randomized still).

Older Population Education: See this post on the topic[1]. The point she makes is that the reduction in covid by age group should have been equal if masks worked equally, but the results from the study show that the reduction in cases was mainly in the older age groups.

[0] https://www.cdc.gov/quarantine/masks/mask-travel-guidance.ht...

[1] https://twitter.com/Emily_Burns_V/status/1433122687765856259

[midasuni]

Cases in Scotland with mask laws and Hugh adherence seem higher than in England which doesn’t have laws and has low adherence.

Be interesting if anyone has done a proper comparison between say Glasgow and Manchester.

[ricardobeat]

I think I’ve heard that before, but how is it higher? From the usual dashboards Scotland has 130 cases per million, while England is at 150/million. The number of cases right now is also stable while the UK overall is going up?

[midasuni]

I last checked a couple of weeks ago when Scotland was on 370/100k and England on 350/100k, seemed to have flipped back the other way now

[ed_balls]

it's hard to compare cases without knowing how many tests were done and how they are administered.

[ralusek]

And where in a particular wave a given place is. And what the seroprevalence and other demographic factors are between the two populations.

[Klinky]

Vinay Prasad seems to be a contrarian who recently compared the US COVID-19 policies to Hitler's Germany[1]. In the article you linked, he's citing his own study on cloth masks. Most would agree that cloth masks are the least effective masking option at stopping viral spread. Cloth masking is just the easiest target to attack in an anti-mask agenda. He also implies doctor's have inherent bias against HCQ and Ivermectin, while being pro-mask.

Basically the dude has his own biases and agenda here, and the study he cites isn't a definitive nail against mask wearing.

1. https://vinayprasadmdmph.substack.com/p/how-democracy-ends

[timr]

> In the article you linked, he's citing his own study on cloth masks.

This is a blog post summarizing his review of every study on masks ever conducted. So yes, he's citing that. You should read it.

I linked to it because most people won't have time to read 30,000 words on masks, and want the TL;DR.

Everything else you've said is an ad hominem.

[Klinky]

His review is targeting the weakest mask type while cherry picking and downplaying even from studies showing benefits of masking, such as the Bangladesh study others have cited, to paint the picture he wants to paint.

[timr]

Read past the title. It covers all masks, not just cloth facemasks.

[Klinky]

I have. I've skimmed through the PDF, and it seems he wants to highlight the "ineffectiveness" of cloth masks, and downplay benefit from other types. It is also odd to put "cloth masks" in the title, if that is not the main focus of the review.

[titzer]

> To date, I'm aware of no study that has quantified a difference in infection, hospitalization or death that is attributable to travel bans.

You have got to be joking, because NZ, Taiwan, and Australia all achieved COVID zero by effectively quarantining their countries, i.e. travel bans. It's basic logic that viruses cross borders and oceans via infected people, not by wafting magically through the air.

That said, travel bans are only effective in the very early phase, when infections are near zero. The US, Europe, and most of Asia are highly connected and by the time COVID infections were spreading, it was pretty much too late. Also, the US's travel bans were not particularly ineffective. Like the US's entire response, haphazard, half-hearted, and actively opposed by lots of weaponized ignorance.

[markdown]

> To date, I'm aware of no study that has quantified a difference in infection, hospitalization or death that is attributable to travel bans.

Why would you need a study to tell you that if nobody with covid travels to a country, that country remains covid-free? Perhaps you are unaware, but there are countries on this planet that covid hasn't gotten to, and those countries have travel bans.

[Robotbeat]

Yup, this is such a huge pet peeve of mine. Throwing away science in the name of empiricism. What I mean by that is that science is about understanding the world by being able to make certain empirically verified models (mathematical usually), and then using the validated models (such as the germ theory of disease) to predict what the results would be even if we haven’t already measured that exact thing.

Like, because of an experiment done on Wednesday, a piece of meat kept carefully covered with metal is not going to sprout maggots and flies. Because maggots and flies are caused by flies laying eggs. That same piece of knowledge can then be used to predict with decent certainty that you’re still not going to sprout maggots and flies if you cover it with glass instead of metal and do it on a Tuesday.

Germ theory of diseases says if you quarantine travel, you can prevent (or reduce probability of) novel COVID diseases sprouting up in your country. Because the disease is caused by germs carried by infected people during the few weeks they’re contagious. You don’t need an exact study to prove that, although it’d certainly be nice.

Seriously. Empiricism is great. Using a kind of mindless empiricism (“models don’t tell you anything, so unless every situation is measured, you have no idea”) to throw doubt on science is not.

[titzer]

The same applies to "lockdowns don't work." That is obviously complete BS considering there are plenty of examples of lockdowns that did work (e.g. the Aug 2020 lockdown of Victoria, NZ lockdowns, Taiwan, South Korea). But lockdowns can fail easily with noncompliance and inability to effectively quarantine the infected.

It's like saying boats don't work after trying to build one out of grocery bags or untreated plywood. Yeah, crappy boats are going to have leaks. Lockdowns are hard; it's not something we really practice (and worse, there are malicious defectors who want lockdowns to fail). A lot of people, we have learned, are selfish and unwilling or unable to make any sacrifice, even in the face of severe collective consequences, and worse, will sabotage efforts either for political gain or just the sheer pleasure of watching everyone else fail (and die!). I really don't know how we can expect global society to continue given how craven some people are.

[timr]

At this point, that list comprises North Korea, Turkmenistan, and a collection of microscopic islands in the South Pacific.

At least some of those are lying.

[GekkePrutser]

While true, it only provides protection during the duration of the travel ban. And at the same time gives the population zero exposure to the virus and no chance to build up antibodies. So when it does hit, it will be like day 1.

So it's perpetually locking you into travel bans to be effective, which is in itself very harmful to a country in today's world.

It only works if everyone did it and you succeed in killing the virus. Right now that is no longer possible because the animal kingdom will keep it alive.

[markdown]

Well that's obvious. No country plans to remain isolated forever; only until a significant population has been vaccinated. Fiji are opening up to the world on December first now that 90% of the eligible population are vaccinated. New Zealand will remain closed until April because their vaccination was delayed by letting less developed nations get first dibs to the vaccine.

[scotty79]

What about truck drivers?

[msie]

"In October 2021, Prasad prompted social media controversy when he published a blog post comparing the U.S. COVID-19 pandemic response to the beginnings of Hitler's Third Reich. Bioethicist Arthur L. Caplan said that Prasad's arguments were specious and ignorant, and science historian Robert N. Proctor said that Prasad was "overplaying the dangers of vaccination mandates and trivializing the genuine harms to liberty posed by 1930s fascism"."

https://en.wikipedia.org/wiki/Vinay_Prasad

[ahdh8f4hf4h8]

Theoretically masks would be much more effective than this - I think the 30-50% number came from a study where they looked at actual non-professional usage of masks. Most people have bad mask hygiene, so there is substantial air leaking around the nose or chin. Many of the makeshift masks people used are insufficient to capture viruses, but they do greatly reduce the "blast radius" of your breathing and coughs.

[stjohnswarts]

If both parties are wearing proper masks then it is 90-95% particle blocking and limiting of viral loads