
Masks Don’t Work – A review of science relevant to Covid-19 social policy - teknico
https://www.researchgate.net/publication/340570735_Masks_Don%27t_Work_A_review_of_science_relevant_to_COVID-19_social_policy
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lukev
I don't understand why people feel the need to say stuff like this. It's
dangerous and wrong.

Yes, sure, masks are ineffective if you define "effective" as "a complete
barrier to infection". Congratulations, you've successfully unmasked the the
grand mask conspiracy.

Except that definition is next to useless. What masks _do_ do is _reduce_ the
amount of aerosolized particles that are emitted and inhaled. It's not meant
to be a protective barrier, it's meant to be a numbers game.

Saying masks are useless is like saying you can catch Covid from your mailman,
so if you accept mail packages you may as well just go to a concert.

It's all about volume and probability of contact.

I'd also be interested to hear someone with more knowledge of the science
weigh in on the studies he cites. If masks are as completely useless as he
claims, I would expect the (already high) infection rate among medical
providers to be even higher, at 100%. What gives?

~~~
DanBC
People make two claims for masks.

1) They prevent the wearer from getting the virus from other people.

2) The prevent the wearer giving the virus to other people.

People talk a lot about viral load, and about breathing droplets deep into
your lungs. So, (2) doesn't make much sense to me. The person with mild
covid-19 infection places a mask around their mouth and nose, thus trapping
all those infected droplets, which then get breathed back in. If the mechanism
of action really is "breathing the virus causes severe infection" why would
you want to trap the virus by your mouth and nose?

> If masks are as completely useless as he claims

They're not saying they're completely useless. They're saying that lots of the
people wearing masks expect 100% protection, even if they're doing fucking
stupid things. There's absolutely no point in both wearing a mask and going to
a football match.
[https://www.thenational.ae/image/policy:1.998514:1585469410/...](https://www.thenational.ae/image/policy:1.998514:1585469410/337768-01-05.jpg?$p=bbe75aa&w=1136&$w=ec52ab9)

If we're going to force people to wear masks we need to make sure they're
wearing them correctly, because an incorrectly worn mask may do more harm than
good.

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bootlooped
The first linked study, the one from Japan, had 32 participants that finished
the study and there were only 2 colds observed, one in each group. To me, a
layperson, that feels like such a small sample size to be totally useless. Am
I wrong about this?

It's also stated, "The main transmission path is long-residence-time aerosol
particles (< 2.5 μm), which are too fine to be blocked". Why when I look at a
CDC article on masks does it say N95 is effective on this particle size?
Unless the author is using "blocked" to mean "100% prevented from moving
through the filter", which would be a higher standard than N95 masks claim to
have.

[https://blogs.cdc.gov/niosh-science-
blog/2009/10/14/n95/](https://blogs.cdc.gov/niosh-science-
blog/2009/10/14/n95/)

~~~
zzzcpan
Both surgical masks and N95 masks can filter out 2.5 μm particles coming in,
the author even cites research showing no difference between them, but it's a
trolling piece, not a scientific paper. The author claims a lot of ridiculous
things.

------
JPKab
Jeremy Howard (of FastAI) is doing a major metastudy on masks at the moment.
Pretty sure they work.

~~~
magduf
Correlation doesn't guarantee causation, but the Asian countries where mask-
wearing has been commonplace for a long time have done far, far, far better
with this pandemic than nations where no one wears masks in public.

~~~
zinclozenge
> Correlation doesn't guarantee causation

This is a vacuous statement in this context and adds nothing to the
discussion, because you can never prove causation via a study/experiment, only
reject the null hypothesis.

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throwaway743
_If the neuroinvasion of SARS-CoV-2 does take a part in the development of
respiratory failure in COVID-19 patients, the precaution with masks will
absolutely be the most effective measure to protect against the possible entry
of the virus into the CNS._

Can be found in the document under "Supporting Information" at the following
address:

[https://onlinelibrary.wiley.com/doi/full/10.1002/jmv.25728](https://onlinelibrary.wiley.com/doi/full/10.1002/jmv.25728)

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DanBC
I've been fairly strongly anti-mask. I'm not sure the linked paper is
persuasive.

I prefer the papers mentioned here (which argue against my anti-mask position
and are changing my mind a bit): [https://www.fast.ai/2020/04/13/masks-
summary/](https://www.fast.ai/2020/04/13/masks-summary/)

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Zenbit_UX
Hey doctors in ICUs right now, masks off! You heard it here first folks, a
study says masks are pointless despite all common sense and decades of usage
in hospital settings.

Anyone want to take bets before this information is tweeted out by potus and
on infowars?

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cbm-vic-20
Masks tell me who is taking this thing seriously, and who might not be.

~~~
skat20phys
In what direction? I think part of the point of this paper is that most masks
aren't taking things seriously enough.

~~~
magduf
No, the point of this paper is that masks are not completely, absolutely,
perfectly, 100% effective and foolproof, and therefore we shouldn't use them
at all.

I really have to wonder if the people pushing this have some kind of agenda.

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teknico
Is this accurate?

~~~
elmerfud
I can't comment if his paper is accurate without investigation of all the
citations. In general masks are meant to stop larger particulates than what
viruses are, that includes the n95 masks. Also medical masks and shields are
intended to protect the wearer more than they are too prevent the wearer from
spreading their infection. Breathing out puts positive pressure behind the
mask causing it to bypass any filtering effect of the mask.

Cloth masks are a complete joke as far as preventing spread unless you're
someone who constantly sprays spittle when they talk. If you are that person
then no one wants to be in spray range already . Cloth masks will barely
filter dust out. The anecdotal story I share about the masks being more about
a social construct than a medical one is this. My wife works in reception at a
medical office. They started requiring all staff to wear makes but those in
non-paitent facing roles (like her) only get cloth masks. They acknowledged
that the cloth masks did nothing to prevent the spread but it was important to
make masks socially acceptable.

The papers closing does seem to have the conspiracy angle to it which I can't
comment on if this is the case or not but overall there does seem to be quite
a bit of "virology theater" going on with policy making.

~~~
d1str0
Cloth masks can definitely help though. They are good at one thing in
particular, reducing spread and velocity of air movement from your face. If
you breath, cough, or sneeze, the transmission distance is highly reduced. You
still have virus escaping, but it cannot travel as far.

~~~
magduf
This is the key here, and what all these "masks don't work!" people seem to
constantly miss somehow. No, masks are not 100% effective at filtration; any
idiot can see that. They don't have to be 100% effective, they just need to be
better than nothing, and that'll slow the spread of the disease. Keeping
people from spewing germs 20 feet when they sneeze or cough is a big help in
slowing this pandemic.

There's a reason masks have been commonplace in Asia for many years now:
they're meant to protect society, not the wearer. When someone thinks they're
sick in Japan, they're supposed to wear a mask to keep _everyone else_ from
getting sick: it's good manners. It only works when lots of people are doing
the same thing.

Similarly, the cloth masks are actually called "surgical masks", because
they're normally used in surgery. They have absolutely nothing to do with
keeping the surgeon safe from the patient; they're in place to keep the
patient, who has a huge gaping wound in his body, from being infected by
droplets from the _surgeon_ as the surgeon bends over the wound site, and is
breathing and talking to other people.

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vangelis
Paqing idlewords.

