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.
- 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! :-)
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.
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!
Thank you for perfectly illustrating the problem. I was actually sort of worried that people wouldn't take me seriously when I said that science has become so political that we actually can't do any. It sounds conspiratorial, doesn't it? But, alas:
1) I post results of RCTs showing that masks do little, if anything.
2) Someone replies that the evidence is insufficient for reasons X, Y, Z.
3) I say "great, let's gather more evidence to resolve those uncertainties".
4) Someone replies "we can't, it's unethical".
Quite a fine castle you've built on that cloud, good sir. Very safe indeed.
Not the least because it would be completely infeasible. You may pretend that we can "simply" do a "controlled experiment" but you ignore how impossible it is to tell any sizeable group of people to behave in a certain way and report honestly about it.
"Randomised control trials" are the platonic ideal but in the real world, you can't endanger people for your curiosity, and you will have greatest problems to actually enforce your test protocol. It's more than "tricky". Unless you have access to some spherical people in a vacuum.
* The pandemic is affecting 8,000,000,000 people all around the world. A large size RCT enrolls X0,000 participants. For example, the Pfizer covid mRNA vaccine clinical trial had 21,728 placebo participants. For every RCT participant, the RCT results are going to inform the course of action for hundreds of thousands of people. This is to say that such RCTs are extremely valuable given the high infectiousness of the virus.
* The risk to the participants is at worst a moderate increase in the chance of being infected with covid. The covid fatality risk to a healthy adult is small. In the US there have been about 50,000 deaths with covid in <50yo age group. An RCT with 20,000 <50yo people on the placebo arm may see about 3 covid deaths assuming all the placebo participants are going to be infected. Realistically, only a fraction of participants are going to actually be infected with covid, thus there is a good chance every single one of the RCT participants will continue their lives just fine, especially if the study designers are careful to not include people with serious comorbidities.
* Vaccines are available to reduce the death risk by another order of magnitude if deemed necessary. Alas, while the vaccines have strong effects in preventing serious covid, they only have a middling effect on preventing infections [edit: after a few months]. The mask/no mask infection effect remains measurable.
* Covid is endemic. Everyone is at risk to to be infected with covid sooner or later. Wearing a mask may decrease the daily risk by a moderate margin, unfortunately integrated over many days the infection probability approaches 1. The RCT is merely speeding the risk by a moderate margin for the placebo arm participants.
* There is a large pool of potential volunteers that don't (want to) wear masks anyways. Adults have the right to volunteer for risky activities, including activities that may result in death.
>* There is a large pool of potential volunteers that don't (want to) wear masks anyways. Adults have the right to volunteer for risky activities, including activities that may result in death.
This is certainly true. But the difference is that once we begin performing medical studies that ask this of people, the medical industry is now complicit in adults performing risky activities that may result in death and is asking people to do so, or if doing so, to do so for the benefit of medical research. This is a line that has not been crossed by the modern medical research industry as it has been long decided that this extra pressure, however small, is a lever they do not want to pull because it is fundamentally incompatible with 'Do no harm.'
It isn't 'do no harm, except a little when we think it might outweigh the downsides'
It's a line I don't think we should cross. I understand why someone would disagree with that.
In a First, Randomized Study Shows That Masks Reduce COVID-19 Infections
A large study co-authored by Yale SOM’s Jason Abaluck and Mushfiq Mobarak tested the effectiveness of a mask-promotion program in Bangladesh in increasing mask use and preventing symptomatic infections. The study found that masks significantly lower symptomatic infections, especially among older people and when surgical masks [instead of cloth] are used.
https://insights.som.yale.edu/insights/in-first-randomized-s...
The fact that we don't is an indication of how hard it's been to pursue any sort of science in this area. Almost nobody funds it, you can't get it published if it doesn't fit the public health narrative, and even if you do, the the news media won't report on it, and it might just get censored on social media.
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.
>>"I'm doing great without one. No need to worry about longterm risks from a rushed vaccine. 1 year does not equal 10. Ever."
There are categories of knowledge where I'm profoundly uninterested in any individual's experience (best friend or stranger on the internet alike:). Simply put - a person surviving Russian Roulette does not make playing Russian Roulette a good idea, no matter how convinced they are and loudly proclaimed that it worked out great for them :).
I do not know your situation - maybe you've gone hermit; maybe you're in an area of low risk; maybe you're being careful; maybe you're the one asshole around and everybody else is vaccinated/wearing mask/implementing lockdown while you're taking credit for not getting your sorry ass sick; or (most likely but I have no way of judging), you're just lucky - see the Russian roulette above.
But in risk evaluation of this sort, again, I'm far far more interested in verifiable statistics than individual's lived experience.Don't get me wrong - we can have a nice round of drinks and talk about how last year's been to us and approaches we've taken and it'll be interesting and we can share; but it's not a policy-guiding thing.
I can get hit by a car when I walk down the street, but I've been doing it my entire life and I'm still here. I can die in a horrible plane crash when I fly, but I still do it. I can have a heart attack when I go to the gym, but it's still a net positive for my life.
Do you have a grasp on the actual risks involved here? You do realize that, even unvaccinated, unless you're elderly or obese or severely immunocompromised, the risk from this virus is measured in fractions of a percent, right? And if you've had even a single dose of an approved vaccine, you can take that number and divide it by 10?
At some point, you have to let the terror go.
> my understanding is that it does not confer individual invulnerability.
Who promised you invulnerability?
But you make an excellent point: the average NYC citizen probably takes bigger risks crossing the street on a daily basis than she would by going un-masked.
The Thing that makes covid tricky is which actions am I making for myself vs others. Safety belt and helmet are largely for myself (but still enforced in many places due to agreed societal cost that goes beyond Individual). Mask, we don't have common universal agreement to yet. (this is not to say I don't have am opinion on it, but I understand looking around that while mainstream it's not universal).
So while I think we have agreement in framework, we may disagree on personal implementation. Mostly, I don't know that I agree with "at some point you have to let terror go". This ain't over yet, may never be over, so some mitigation steps may never be over, is the sobering world to raise offspring Into. Alberta took foot off the brake for just a little while and next thing they were begging other provinces for ICU spots. And there's a whole conplicated interlocked system of individual causes and effects rather than some simple binary rule that have rise to that reality.
As of the week before last, 28% of all hospitalizations in my state (NM) related to COVID19 involved fully vaccinated people.
Also, the eldest people (largely those most at risk of hospitalisation) are substantially more likely to have been vaccinated already, no?
None of this is an argument against vaccination, of course.
Ah, so this is the real reason. That's fine, but it's also not really applicable to the wider population and hence isn't about what I originally asked -- which is why we would universally continuing wearing masks forever.
The answer is we wouldn't, because that makes no sense.
Now, I look forward to it being more socially acceptable to wear masks when you have an infection.
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?
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).
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.)
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.
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.
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.
I live in Virginia, FWIW.
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.
Be interesting if anyone has done a proper comparison between say Glasgow and Manchester.
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-...
> 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
> 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
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
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.
Regardless, the paper covers pretty much ~all of the prior literature for masks and respiratory illness.
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.
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.
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.
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.
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.
At least some of those are lying.