Data do not back cloth masks to limit Covid-19, experts say
cidrap.umn.edu
cidrap.umn.edu
This is part of the standard academic fake science pipeline. The researchers did reasonable work (best summary: "We don't know how well they work"). The university PR departments turned that into hyped-up nonsense to gain publicity and brand recognition. Next step will be science reporting, which will exaggerate the press release, and finally, popular news, which will use this to bash random policy decisions.
Direct link to the original paper:
https://www.nap.edu/read/25776/chapter/1
In general, NAP pieces tend to be well-researched and well-written summaries of what's known. This one is no exception.
Self-promotion tends to help specific universities and researchers. If my name make NY Times, that's a big deal. On the other hand, blame is diffuse. People start to distrust the scientific establishment as a whole.
Successful scientists themselves tend to grandstand and overstate their work when talking to the popular media. Idealistic grad students don't do that, but idealistic grad students also don't get faculty jobs and later tenure (politically savvy graduate students do).
Unfortunately, dishonest, shameless self-promotion is how one gets ahead in the academy, and how universities get ahead of each other, even if it is a lot like pissing in a big, common, shared pool. You get a slap-on-the-wrist for bad research results in a scientific journal. That doesn't happen for the popular press.
It depends on the school too. I'd love to see a replicability study based on school tier. I bet hyper-competitive schools (Stanford, MIT, Harvard, and the rest of the Ivy+) would come in far behind state schools for replicable results.
This echos the same thing that happens with the WHO. And given that these are huge, central institutions - they need to take more care around how their pronouncements are received.
With COVID-19 I see fair amount of articles when a scientist says "We don't have (strong) evidence for X" and an article hints that X is not true (without saying this explicitily).
I don’t think it’s fair to criticize people who said masks aren’t effective, though. It happens everywhere I look. China’s anti-US propaganda video mentioned this. It’s even here on HN. The reality is we don’t know much yet, and this is supported by current research. My understanding is it’s a better safe than sorry measure.
What really bothers me is this is just one example of people turning against each other. Now more than ever we need to be united, not fighting.
It’s entirely possible that cloth masks are net negative due to: 1. False sense of security meaning people interacting closer to each other or 2. People touching their faces nonstop adjusting their mask
People had the same line of reasoning for treating people with HCQ, and it’s beginning to look like HCQ might be safe for healthy patients but a death sentence for COVID patients. Even if this ends up not being true, it is absolutely possible that it is — which is why we need to learn more and do so very carefully.
Life sciences is full of counter-intuitive results, many of which were learned through tragedy. That’s why the scientific community is so gosh darn careful about statements like, “it’s better safe than sorry.”
If we don’t know whether it works, then we also don’t know whether it’s better safe than sorry.
In a short term a person without protective equipment (e. g. helmet) may behave more cautious, but after some time I expect behavior to regress to a normal pattern regardless the use of PPE: it is very hard to be on high alert for a long period of time.
Just like what we should be doing with regards to masks.
The title implies that we have data showing cloth masks don’t work, but what the article actually says is just that we don’t have data.
Data does not back that if you (anorphirith) shoot me (wegs) in the head with an AK47, I'll die. That particular study has never been done). But we know it's true. But a carefully-phrased headline gets picked up by the popular press and builds university branding.
See also "significant" (which means "statistically significant," so might be a 0.000001% effect size with enough data, but which the public picks up to mean "big"). These are well-developed techniques for roping science-ignorant reporters.
Also, most governments advice people with a cold/fever/… to stay home. If they do, and given the current estimate of infection rate, those droplets aren’t likely to contain the virus.
https://download.nap.edu/cart/download.cgi?record_id=25776
The actual paper consistently says that homemade masks really DO work, at least to some extent.
Video of droplets blocked by a mask:
https://twitter.com/i/status/1254535446509412353
Why we should all wear masks:
This feels like the parachute example to me that was posted here a few days ago. You don't need to do a study to prove that a man hitting the ground at 10km/h would be more likely to survive than one hitting at 150km/h. Sure, parachutes can fail, but how can they be worse off than NOT wearing a parachute?
It almost feels like the health agencies were caught with their pants down telling absolute lies about masks for over a month and are now scrambling to salvage some dignity from the affair by throwing studies at us. Just imagine how much we could have reduced transmission if Americans had started wearing masks in late February or at least early March.
This lie has literally cost the world billions of dollars, not to mention thousands of lives.
In contrast to the intentionally dishonest UMN fluff PR piece, that's what the NAP paper it claims to summarize says.
The one really big effect not talked about is that it also means I can't unconsciously touch my mouth or nose. Remember the "don't touch your face" campaign?
The article title is "data do not back cloth masks to limit Covid-19".
The NAP paper says:
"The evidence from these laboratory filtration studies suggests that such fabric masks may reduce the transmission of larger respiratory droplets. There is little evidence regarding the transmission of small aerosolized particulates of the size potentially exhaled by asymptomatic or presymptomatic individuals with COVID-19. The extent of any protection will depend on how the masks are made and used. It will also depend on how mask use affects users’ other precautionary behaviors, including their use of better masks, when those become widely available. Those behavioral effects may undermine or enhance homemade fabric masks’ overall effect on public health. The current level of benefit, if any, is not possible to assess."
It seems like an entirely accurate summary of the contents of the paper.
I get your argument but unlike a man crashing to death, we are playing a probability game here. Viral load also matters, even if you can stop some of the virus from entering, it can only help.
If you would otherwise self-isolate if you didn't have a mask, the mask has increased your chances of getting yourself and others sick.
It should always have been a combination of mask wearing from day 1 and stopping any large gatherings. Combine that with social distancing and you get most of the benefits. Now we have already infected so many people and are trying to close the barn door when the horse has long fled.
Before the lockdowns people were going about their merry lives WITHOUT masks. If they were doing exactly the same things but WITH masks, we would still be better off.
A coordinated advice in this case is important. Without a central authority advising for masks, people who do choose to wear them look like loony conspiracy theorists, but if there is central guidance for doing it, it quickly changes public perception.
The mask advice should have come in February, followed by bans on large gatherings (25+ people or some number), and then the lock downs could have come in a limited fashion in March as needed.
All those cute videos of cutting TShirts and socks and what nots to make masks could have been shown in Feb and people would have used them. Instead the authorities chose to tell such a stupid lie that it's almost insulting to our intelligence.
https://twitter.com/Surgeon_General/status/1233725785283932160
U.S. Surgeon General
@Surgeon_General
29th Feb.
Seriously people- STOP BUYING MASKS!
They are NOT effective in preventing general public from catching #Coronavirus,
but if healthcare providers can’t get them to care for sick patients, it puts them and our communities at risk!
http://bit.ly/37Ay6Cm
What is surely to happen after this debacle though, is that many official recommendations and plans will have to account for pandemic outbreaks and remedy many of the shortcomings of current funding cuts.
This is true. Masks don't protect you from catching COVID-19.
Masks may lower (but not eliminate) spread of virus particles. We don't have any evidence that this reduces infection rate, but it's plausible, at least for droplets.
If the virus spreads mostly by aerosol however, then mandated masks are probably counterproductive, because if the government says "wear masks" the people will hear "wear masks and you'll be fine", because that is what they want to hear.
All you smart rational types out there might not think like that, but I have heard this reasoning first hand from ordinary people. It's a real problem.
I understand wanting there to be enough for HCWs. If so, say that without the lie. If there aren't enough for HCWs, restrict purchase by the general public and say that they will be available to the general public when there are adequate supplies.
When the health authorities lie to the public, they lose credibility, and they need that credibility if they're going to ask people to do extreme things like not leave their houses for an extended period of time.
It's really just like a condom. They work, some better than others, but none are perfect. The general public can understand that.
Cite me some evidence that shows that simple (non-FFP) masks or surgical masks protect the wearer against any virus. To the best of my knowledge, There isn't any such evidence and it's not scientifically plausible that they would protect.
> If masks don't protect you from getting COVID, why do healthcare workers wear them, and why should we reserve for them a product that doesn't work?
Because healthcare workers do get infected (a lot) and you don't want them to spread the virus (or other pathogens) around either.
We also need to differentiate between FFP masks which may offer some protection against viruses and surgical masks, which do not. It is mainly the FFP masks that are in short supply.
> When the health authorities lie to the public, they lose credibility, and they need that credibility if they're going to ask people to do extreme things like not leave their houses for an extended period of time.
Maybe, but that statement I quoted is strictly not a lie.
> It's really just like a condom.
No, it isn't, not even close. It's like avoiding pregnancy by wrapping your dick in a piece of linen. It just doesn't work. There's no evidence that it works. It's not plausible that it would work.
> The general public can understand that.
You, presumably intelligent and well-educated, don't even understand it. You still believe the mask protects the wearer when it does not. I have no hopes the general public will understand it.
To be clear, I'm not against wearing masks because I hope that it can reduce droplet infections and it's a net benefit. That's just my hope though, not my firmly-held belief.
Even a surgical mask provides protection to the wearer. A professional-grade surgical mask provides N95 level filtration, it just doesn't seal to the face like an N95. That means that some of the air coming in will not be filtered. However, much of it is, and larger, non aerosolized ballistic droplets will be stopped and absorbed by a mask.
It doesn't.
> Have you looked at the scientific literature on this?
Yes, I have, including this particular review as well as several of the reviewed papers.
I have yet to find a single convincing study that shows that simple masks protect the wearer against viruses. If it existed, people would be waving it around and governments would have no reason to not ask people to wear them. Simple masks were never in short supply.
This review makes abundantly clear that virtually all the studies are of poor quality. Note that the effect found in this review is not that large (+13% over washing hands) whereas the effect of wearing a gown is much larger (+27% over washing hands). Yet I haven't seen any big discussion on what kind of gowns people should be wearing out in public.
There are a number of reasonable arguments. Just a few:
* people who wear masks touch their face more often, which leads to greater infection (I personally observe this every day).
* masks give people a false sense of safety, and cause them to reduce social distancing.
* masks increase risk of infection unless donning and doffing procedures are followed correctly.
* telling people to wear masks causes them to seek out medical masks and N95 masks that are in short supply, and should be reserved for professionals (also personally observe this every day; people are walking their dogs in Manhattan wearing N95 masks, while hospitals literally beg for new masks).
Unless you record yourself and count the number of times you touch your face while wearing a mask, your recollection is unlikely to be objective or accurate.
Here, I made another one—
> If you are wearing a mask while others are not, they are likely to ask you about it, which makes it more likely for you to talk in their presence, thus increasing the chance of transmission.
Given how the authorities flipped their advice in barely a month, despite having the same laundry list of arguments, shows that the arguments were more of a deflection than something that was properly incorporated into the cost-benefit analysis.
It's also consistent with a recommendation made for non-scientific reasons. The science here hasn't changed, but the recommendation has.
Everyone on the street observed social distancing with me. As with most anti-mask excuses, statements didn't match reality.
”The use of medical masks in the community may create a false sense of security, with neglect of other essential measures, such as hand hygiene practices and physical distancing, and may lead to touching the face under the masks and under the eyes”
(Note that infection can take place via your tear ducts. https://www.drtavel.com/blog/can-you-catch-a-cold-through-yo...: “Rubbing your eyes after coming in contact with an infected person is one of the most common ways to catch a cold.”)
This was not in the article, I am just speculating on a possible reason (not applicable here).
BTW our gouvernement (French) was telling us that story of no masks for the first weeks and it was already ridiculous at that time.
The term is “blow by”, and it’s worth at least learning about.