If only 40% were to wear masks, they found almost no benefit.

By "masks" they don't just mean N95 masks. They include surgical masks, scarfs and bandanas used as masks, and other homemade or improvised masks.

Here's an article about that study [1].

For those who don't want to make their own or improvise, masks are becoming reasonably available. Newegg, for example, has several sellers which a search there on "masks" will find [2]. This includes some with stock in the US ready to ship, with delivery in a week or less. I just bought 50 disposable surgical-style masks for $30 from this listing [3], and they arrived in just over a week. At the time I bought they shipped from the seller but since then Newegg is handling shipping.

I picked that seller because they shipped from the US. A lot of sellers ship from China. Many of those do have reasonable shipping time, but I have no idea if the US Customs and Border Patrol is still seizing and redirecting PPE supplies that cross their paths. I figured a shipment that was entirely domestic was less likely to fall prey to government fuckwittery.

Tom's Guide has been maintaining a list of places with masks avaiable, which they update frequently [4]. That was were I learned that Newegg had masks in stock.

[1] https://www.vanityfair.com/news/2020/05/masks-covid-19-infec...

[2] https://www.newegg.com/p/pl?d=masks

[3] https://www.newegg.com/picotee-face-mask/p/0CE-02AC-00001

[4] https://www.tomsguide.com/news/where-to-buy-face-masks-and-c...

"The factor by which β was reduced was conservatively set to 2."

"Varying degrees of mask effectiveness are modelled by the mask transmission rate T and mask absorption rate A, which denote the proportion of viruses that are stopped by the mask during exhaling (transmission) versus inhaling (absorption), respectively. Weset T = 0.7 and A = 0.7 to model the use of inexpensive, widely available, and even nonmedical or homemade masks [...]"

So basically, they assume certain values for how effective masks are, and then simulates the dynamics of the epidemic. Nowhere do they try to justify the specific values chosen.

I expect that the conclusions cited (if only 40% wear masks, there is little benefit; if 80% wear masks, total cases go down by a factor 1/12) to be heavily dependent on those assumptions, and so I would be cautious to read too much into it.

Link to paper: https://arxiv.org/pdf/2004.13553.pdf

This is a disease that is spread by breathing in air contaminated by a infected person coughing or talking.

Nobody uses the phone (it's bad manners here), so like the only time anybody talks is like when a group of people gets on together (not usually the case when I commute).

I mainly bike so my subway experience might not be very typical, but it's one anecdata point.

Almost all my subway-riding experiences this year have been such that 95% of the other passengers are wearing masks, and nobody talks.

Can't be the main factor, but it might be one factor.

Could be though. It's just interesting that they pulled it off without any lockdowns. It could be their isolation as an island as well.

It seems only China is being overly cautious, implementing lockdown-type measures on a Russian border city with 130 confirmed cases

To be honest, i suspect the movement restrictions are less about the virus now and more about controlling the "low end population" and other working class people. (Middle class people tend to live in gated communities anyway so the government didn't need to put up fences to control their movements.)

In short, China is definitely still being overly cautious, and it's not just up in the north.

Countries in Asia not hammered by the virus: Indonesia, Philippines, Thailand, Japan, Singapore, South Korea, Taiwan, Vietnam, Malaysia, Mongolia, Myanmar, Laos.

I'd add China to that list, however absolutely nothing about their reported figures can be trusted. All authoritarian nations are very aggressively lying across the board about their numbers (North Korea as another example). Russia is in a similar situation, they're undercounting cases and deaths to an absurd extreme (half the deaths of Canada, with 4x the cases; Britain with 10x the deaths of Russia, with fewer cases; yeah right).

It makes little sense to pretend it's masks making all the difference for all of them. Indonesia, the Philippines, Malaysia, Vietnam, Laos, Myanmar, Mongolia are extremely poor and there's no evidence it's some kind of cultural hygiene action protecting them all (an often floated contributing theory for Japan or Singapore).

Cities in Vietnam and Indonesia didn't avoid an outbreak like Wuhan / Milan / Madrid / NYC thanks to instantly 100% masking up back in November - January.

Based on what we now know about SARS-CoV-2 there are only a few reasonable explanations (some of which blend, multiple factors).

Being on an island blatantly helps, just ask Hawaii and New Zealand. As with Taiwan, Japan, Singapore, Indonesia and in practical terms South Korea. Australia also largely fits that qualification (their major cities are population islands).

A lower susceptibility due to an unknown genetic factor. We do know that Vitamin D levels are very important, such that darker skin in cooler climates like NYC (cooler during flu season) can be a deadly combination as it pertains to getting a bad case of Covid. Someone on HN stated that 40% of deaths in Sweden are Somali Swedes despite their very small share of the population (5% of Covid cases are Somalis, and they're about 0.8% of the population). Severe Vitamin D deficiency has been repeatedly linked to bad outcomes. This is also an important factor with some other respiratory viruses.

There may be a lot of cases in some of these nations, however they're not producing large death rates due to health factors, specifically far lower rates of obesity, cardiovascular disease, diabetes, etc. If you're an average person and catch a mild case of Covid in Indonesia, you're not going to the hospital for it unless it progresses and you get very sick.

We do know there has been some lying about cases, however it doesn't appear that nations like Indonesia are covering up any mass number of deaths (I've yet to see any evidence supporting the notion that they're hiding eg tens of thousands of deaths).

Many of these nations have not tested at a high level, which may explain some of the lower case rates, however it doesn't explain the lack of large death numbers. Deaths have tended to prompt nations to get aggressive on higher rates of testing, so unless you're seeing a lot of deaths, a poorer nation may choose to avoid the cost of high rates of testing.

There's no question that masking up helps to a huge degree. So to the extent that nations have done that, it has helped them imo (I think the evidence is overwhelming at this point). Japan and South Korea to name two, have clearly seen the benefit from that.

And last but not least, climate. It's likely that the hotter, poorer nations in Asia have had some protection from the virus for the same reason cities in Texas, California and Florida have done so much better than eg Chicago, Boston, Detroit, NYC, Philly, Wuhan, Milan, Madrid, etc. We know the virus, as with influenza and SARS, does not do as well against high temperatures and high humidity. It doesn't stop the virus, it slows it down versus what would otherwise occur. Also, being in a very cold climate (Canada, Finland) would have been a benefit until warmer weather hit (we saw that in Moscow), as it reduces various social activity naturally.

If you were to bundle together: fewer comorbidities, climate, island and masks, you'd have just about an ideal mix of protections (a culture that will consistently respect social distancing would obviously help also).

You've missed Singapore there, which has been hit extremely badly on a per-capita basis. For number of confirmed cases, they're 8th in the world. They're not getting mentioned as often because their very good healthcare means they have few deaths - less than 1%, unlike Sweden [1] where currently 45% of people who catch the virus die from it.

[1] https://www.worldometers.info/coronavirus/country/sweden/

To put this in perspective, this is 10x higher than the initial estimate of 1-3% death rate, and 0.4 to 0.8% fatality rate after random testing became more prevalent.

But you're right that even if you take the 3,992 deaths out of 33,188 confirmed COVID-19 cases in Sweden, their 10% death rate is still almost 10x higher when compared to Australia (1.5%) and much more compared to Singapore (0.08%).