
Data do not back cloth masks to limit Covid-19, experts say - timr
https://www.cidrap.umn.edu/news-perspective/2020/04/data-do-not-back-cloth-masks-limit-covid-19-experts-say
======
wegs
I suggest clicking through to the NAP paper, which unlike this reporting
fluff/hype piece, is very reasonable.

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](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.

~~~
astrophysician
You forgot about the other half of the cycle: time passes, another wave of
publicity bashes the initial hype, people assume the scientists themselves are
responsible (even though they have been freaking out about their work being
misrepresented), scientists lose funding, people don’t trust scientists.

~~~
pacala
You forgot about the third half of the cycle: scientists exceedingly rarely
submit a correction note to tone down the hyped up claims made by the PR
departments / science press. They are very good at keeping the freak out to
themselves. A systemic problem, not sure how to solve for, if even there is a
solution.

~~~
astrophysician
Yea right, it’s just so weird to deal with this problem as a scientist unless
you do work that is regularly in the news and you have opportunities to learn
how to better control what is written/said and deal with instances where the
wrong message is getting out. Vast majority of scientists are doing work for
an audience of themselves, other scientists and funding agencies, and are
working for respect, not fame or media attention. So when a their research
suddenly gets churned through this bullshit cycle, they’re really troubled but
don’t necessarily know the most effective way to control the message once it
gets out of their hands. It can be really unfair and stressful.

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gnusty_gnurc
I feel like there's this bizarre impedance mismatch in communication - that
the internet lends itself to passing around headlines without associating the
proper context/nuance. So in effect, an academic article that ultimately says
that there's no easy way to gauge the effectiveness of cloth masks is passed
around as "Data do not back cloth masks." No one is lying or deceiving, but
the perception received broadly will be wrong.

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.

~~~
citrin_ru
IMHO it happens mostly because of perverse incentives of AD supported media:
controversial statements attract more clicks (and more revenue). Point that
"masks don't work" (even if it is not stated directly, but assumed) is more
controversial than: "we don't know if masks work".

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).

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dkdk8283
Masks have become a political issue, unfortunately. If everyone using masks
doesn’t deprive healthcare workers of PPE I’m all for it.

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.

~~~
ethanbond
“it’s a better safe than sorry measure” is itself a bold claim to be making.

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.

~~~
citrin_ru
False sense of security argument repeatedly used against the use of bicycle
helmets, but I'm yet to see evidence, that having a helmet actually changes
how a person rides a bike in any significant way. And I expect behavior with
regard to masks to be very similar.

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.

~~~
ethanbond
Sounds like a good question to do some scientific research on before resorting
to intuition in either direction (which of course shows the weakness of
intuition).

Just like what we should be doing with regards to masks.

------
procrastitron
This title seems misleading to me.

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.

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ttonkytonk
I have heard that while the virus may spread via microparticles, that's
probably not the main method of transmission or else it would have spread much
more already. Therefore it seems reasonable to believe that homemade masks
might help.

------
anorphirith
The title is inaccurate, they acknowledge on the first paragraph that it
captures large droplets. that's reason enough to wear the mask

~~~
Someone
But large droplets drop to the ground rapidly, so if social distancing is
done, they’re unlikely to infect anybody, anyways.

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.

------
rladd
What's really odd about the linked article is that it's supposed to be a
summary of this paper:

[https://download.nap.edu/cart/download.cgi?record_id=25776](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.

------
paulsutter
Masks are not a risky medical procedure. Anti-mask truthers are the ones who
need extraordinary evidence, not mask supporters.

Video of droplets blocked by a mask:

[https://twitter.com/i/status/1254535446509412353](https://twitter.com/i/status/1254535446509412353)

Why we should all wear masks:

[https://masks4all.co/](https://masks4all.co/)

------
kinkrtyavimoodh
This mask discussion makes me think like I am taking crazy pills. Can someone
explain to me how placing a barrier in front of your mouth and nose can
possibly be a BAD idea when the purpose is to reduce the entry of particles
into the system? Why do we need studies to prove this? If you are inhaling it
is likely to stop some particles from getting in. If you are exhaling it is
likely to stop some particles from getting out. Sure, particles might still
get in or out but HOW CAN IT BE WORSE THAN LITERALLY BEING EXPOSED ALL THE
TIME?

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.

~~~
wegs
No one honest can, because masks do help. What's not clear is how much they
help. They'd have a huge effect on large droplets, but potentially a very
small effect on bioaerosols. Until we know more about how COVID19 typically
spreads, we don't know how important they are.

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?

~~~
timr
_" In contrast to the intentionally dishonest UMN fluff PR piece, that's what
the NAP paper it claims to summarize says."_

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.

