Hacker News new | ask | show | jobs
by GreaterFool 2280 days ago
I keep hearing “masks are useless”. If every person who has any cough or any chest tightness or any sore throat, however mild, put on a mask, wouldn’t that stop the spread?

I live in Japan. It started here earlier but didn’t explode. Nothing is closed. Business as usual. everyone wears masks.

Most cases in Hokkaido. Maybe because it is much colder there and easy to overexposed and tax the immune system.

6 comments

I think some of the logic behind "masks are useless" is that if people believe masks will prevent it, they'll get too reckless about going out as long as they have a mask. Sadly many people wear masks incorrectly and other people will wear masks that don't actually block viral particulates while out there acting more dangerously than otherwise, spreading disease.

IIRC anything below N95 isn't going to do much, and from experience (yay wildfires) I can say wearing N95s is very uncomfortable. Incidentally even physicians wearing proper PPE (n95 or better, etc) can still catch COVID, so it wouldn't be appropriate to say that those are good enough.

It's certainly better than nothing - I'd prefer it if everyone out and about was wearing masks - but the risk of false security leading to dangerous behavior is strong, and we already have issues with mask supplies, so it makes sense to discourage it.

> I think some of the logic behind "masks are useless" is that if people believe masks will prevent it, they'll get too reckless about going out as long as they have a mask.

Lying to people for their own good may be acceptable in some circumstances, but in the long run it's always going to have deleterious effects. It erodes trust, it disincentivizes responsible people, and if the people doing the lying are wrong ... it makes things worse.

https://www.nytimes.com/2020/03/17/opinion/coronavirus-face-...

"Why Telling People They Don’t Need Masks Backfired"

"To help manage the shortage, the authorities sent a message that made them untrustworthy."

That's very convoluted reasoning. I think the main goal of surgical masks for entire population would be to limit amount of virus floating in the air. They are also good at stopping people from touching their faces.

IMO the goverments should make masks mandatory, even if it's DYI mask made from few layers of tshirt. And start teaching people how to use them and why.

If the supply was there I'd absolutely agree. At least in the US it's very hard to get adequate masks right now (this is partly due to a failure to maintain supply, there were some news stories recently about how a local manufacturer was begging the government to invest in this so he could maintain production)
Masks prevent sneezing from reaching other people.
There is a huge shortage of masks in the west - even hospitals are running out.
And that is the only reason for the claim that masks are useless. Of course they are not useless, Chinese aren't idiots.
Oh come on.

A) nobody is making that claim - you are.

So don't turn this into some weird non-fact-based appeal to emotions. The claim that they are useless is because the evidence does not support them. They ARE useful in clinical settings, and heavily required there.

B) there is no evidence for their success:

1) https://www.bbc.co.uk/news/health-51205344 "implementing simple hygiene measures" was vastly more effective." "Although there is a perception that the wearing of facemasks may be beneficial, there is in fact very little evidence of widespread benefit from their use outside of these clinical setting." "routine surgical masks for the public are not an effective protection against viruses or bacteria carried in the air"

2)research study, particularly on leakage: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3306645/

3) efficiacy in Beijin: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5969371/ (again largely leakage)

4) efficacy in 22micron particulate: https://www.ncbi.nlm.nih.gov/pubmed/3470452 (again leakage. but depends on particulate size)

Nobody is making this claim? Since your nickname sounds German, you may be able to understand this text from the FAZ:

"Im Folgenden ist eine Reihe nachweislich falscher Angaben aufgelistet – etwa der Nutzen von Atemmasken gegen eine Ansteckung"

Source: https://www.faz.net/aktuell/gesellschaft/gesundheit/coronavi...

What they claim is that the uselessness of face masks is proven. Not that the usefulness is unproven. That makes a big difference.

For those who don't read German:

"In what follows, a series of provably false claims are listed - such as the use of breathing masks against contagion".

(Native German speakers can correct me if my translation is inexact)

Masks are effective at preventing spread to others, but they're fairly ineffective at preventing spread to the wearer since the virus can get on any exposed skin and make it's way to your mouth (e.g. touching after washing hands) within the 3 hours or so it can survive.

Since we don't know who is contagious, and we don't have enough masks for everyone, they're essentially "useless". They're quite useful for medical professionals because they're more likely to use sufficient caution than the average person, so it makes sense to reduce panic buying for something that likely won't help the average person so more are available for those that really need it.

It's a white lie by the media. If they told the truth to the public then they fear it would deprive hospitals of masks and cause worse outcomes for society.
They're obviously not useless. They do keep spittle down. But every person in public would have to wear them in the off chance they're asymptomatic carriers.

And a virus will still penetrate most masks through the sides where air is mainly being pulled in from. So there is more nuance than just "masks are useless"

I guess you can wear them. But given the choice I'd rather have immunity. And I think we should focus more on that.

Masks decrease R0. You don't need everybody to wear them. You just need enough people to wear them for R0 to fall below 1, combined with all the other measures. It's academic because there aren't enough masks but it's a lesson to learn for a future epidemic. Also it's high time that mask wearing becomes culturally normalised in the West as it is in east Asia.
> You just need enough people to wear them for R0 to fall below 1

This is the point I wanted to make but I went with "everyone" instead of "enough"

For what it's worth, I think you'll find here in the US at least a very pigheaded attitude towards wearing masks. And that includes myself. I just don't want to live in a world where everyone has to wear masks. It's soul crushing.

Droplet infection is only really a problem within a couple of metres - SARS-CoV-2 does not seem to be aerosol spread.
I seems Coronavirus can stay active airborne for several hours.
It's business as usual because the government refuses to increase testing. They're pretending there's no cases because they don't want to cancel the Olympics later this year. For a more realistic figure look at South Korea where mask usage is about as common as here.
I was one of those people discouraging masks a while back here. I was wrong. With what we know now asymptomatic people should have masks if there is a supply available. At the present, that supply isn't available in the US and many other countries, but as soon as it becomes so we need to normalize mask wearing in public for the duration of the pandemic.
I live in Japan too and just spoke with a friend who thinks government is hiding cases to keep the Olympics. Given how hard it seems to get a test (as per the press) this has some truth. People are a bit more careful than in Europe but not amazingly careful either, so the virus is probably spreading silently.
"...so the virus is probably spreading silently"

And harmlessly? Because the outbreaks in Iran and Italy show that the virus, if not contained, will spread rapidly and start killing hundreds every day.

Why exactly is this not occurring in Japan? How do we reconcile the idea that Japan is doing little-to-nothing about the virus with the fact that the virus is not causing nearly the same level of illness or disruption as in other countries?

That certainly seems like something the Japanese government would do. Just look at the Fukushima nuclear issue for evidence of them hiding information to save face. I personally do not trust the Japanese government to be transparent about such things.
It's useless in the sense that you can still contract the virus with a mask. Let's say they are using the surgeon's mask, someone can sneeze and it can get in through the side. The n95 has a better seal so that can prevent it, but what if someone sneezes and it gets into your eye. I would say some protection is better than nothing, but don't assume you will be protected from coronavirus 100%.
100% protection might be important to you personally, but it does not matter on a societal scale. What does matter is to decrease as much as possible the mean number of new people infected per sick person.

If that number is above 1, the growth is logistic (exponential in early stages), if it is lower but still above 1, it is exponential but with a longer doubling time ("flattening the curve"), and if it is below 1, cases will decrease.

>but don't assume you will be protected from coronavirus 100%.

Washing hands does not protects you 100% so why bother?

No! It’s bloody useless because you’re not just receiving it through your respiratory passage, but also eyes. And then you touch a surface which someone has put bodily fluids on and put your fingers in your mouth or rub your eyes.

Masks are excellent for stopping transmission for infectious patients however - because it catches particulates.

Current (and to be fair, there remains some debate but it seems it is really just the precautionary principle) evidence suggests that spread is by droplet. So a mask doesn’t help stop you receiving it. Definitely helps you stop transmitting it; definitely helps healthcare workers who are exposed to high titre loads, and will be working sick unlike the rest of the population,

But the average person can reduce both their transmission and infection by being vigilant with hand washing, masks if sneezing/coughing/isolating, not touching face/mouth/eyes

Leave the masks to the healthcare workers and the infected

If I accept your argument that a mask doesn't stop you from receiving it (which I doubt):

If it were a social norm to wear a mask during an outbreak, and 50% of the population did, it would reduce the spread of the virus greatly. Far from bloody useless. Americans are locked into individualistic thinking: "How will this benefit me?". Also consider asymptomatic transmission.