Summary: Any country can follow a series of measures that are very cheap and can dramatically reduce the epidemic: mandate wearing home-made masks, apply physical distancing and hygiene everywhere, and educate the public.

In Part 1, we showed the paths that different East Asian countries followed during their dance against the coronavirus. Some patterns started to emerge about the measures that matter most.

It’s time to dive deep into all these possible measures, to understand them really well and decide which ones we should follow. We can split them into 4 blocks:

Cheap measures that might be enough to suppress the coronavirus, such as masks, physical distancing, testing, contact tracing, quarantines, isolations, and others Somewhat expensive measures that might be necessary in some cases, such as travel bans and limits on social gatherings Expensive measures that might not always be necessary during the dance, such as blanket school and business closures Medical capacity

During the Dance, when we relax the lockdown and start going back to normal, the goal is to combine measures that get as much economic activity back to normal, while keeping the virus’ transmission rate below 1 — so that it doesn’t spread widely — until either a cure or a vaccine is discovered.

Today we’re going to focus on the very cheap and easy measures that anybody can apply, and the massive impact they can have. Let’s start with the most obvious of them all: Masks

Masks

As we saw in the first article, masks are widely used in East Asia: China, South Korea and Taiwan, but also Hong Kong and now Singapore. But these are not the only countries that trust masks. As of April 22nd, 2020, 51 countries mandate them in some public activities, including countries such as Germany or Taiwan. That’s over 25% of all countries:

Detail of every country’s measures, thanks to Mask4All team

This is for mandates. But many more countries recommend masks, including all of the G7 (except for Italy and the UK). In the US, a number of cities, including New York, Austin, Los Angeles, and San Francisco have passed mandates over the last few days.

But until very recently, we were told not to wear masks. As of April 22nd, the WHO still recommends not to wear a mask if you are healthy. And most countries still don’t mandate them in public. Why? Who is right?

To know the answer, we need to understand the science behind how the coronavirus spreads.

The Science of How the Coronavirus Spreads

Respiratory infections use your mouth and nose to spread through three mechanisms:

“Droplets”: drops of liquid that you eject from your mouth and respiratory tract

“Aerosols”: very small particles that mix with the air and can remain there for hours

Surfaces: for example, you cough on your hand and use a door knob that somebody else touches afterwards

For the coronavirus, many scientists initially thought that most contagion happened through droplets when people coughed, and that these droplets fell quickly to the ground, within a few seconds of the cough and no farther than 2 meters (6 feet). If that had been true, it would have meant that the main way you got infected was if somebody coughed in your face, or if you touched a contaminated surface.

Since usually nobody coughs in your face, authorities argued that the value of wearing a mask was low for average people. But for healthcare professionals, it was huge, because they get these droplets on the face all the time from patients that are sick and cough in front of them, when they intubate them, or in similar situations.

Since there were very few masks available, several authorities around the world decided to prioritize them for healthcare workers, and recommend against their use to the rest of the population.

It was the right thing to prioritize healthcare workers, but instead of saying: “They’re much more useful to healthcare workers, so the right thing is to keep masks for them” they claimed that they were useless—or even dangerous—for the general public. That undermined the credibility of authorities.

Then this evidence started coming.

This video illustrates droplet clouds, and how they can move much farther than 2 meters without falling

This video illustrates research done around droplets, droplet clouds, and how they might infect people

Researchers measured the velocity of coughs. Even a meter away from the mouth, droplets in the center of the cough cloud are moving at about a meter per second (green). These speeds suggest keeping six feet distance from other people may not be enough to prevent the virus from spreading in a cough.

Apparently, in coughs or sneezes, droplets could be carried away much farther than 2 meters (~6ft), and they didn’t fall so fast to the ground. Some did, but many remained in a cloud of droplets.

Source: screenshot from one of the previous videos, showing a droplet cloud

Then, it was discovered that you don’t even need to cough. Singing could be enough. In a 60-people choir in Washington State, 45 members got infected. Even talking is enough:

Or just breathing!

That makes masks very very important. A mask can stop infected people from emitting droplets, and healthy people from receiving them.

But there are no masks! There’s a global shortage of them. The few we have should be for healthcare workers. What do we do?

Thankfully, some researchers have discovered that you don’t need professional masks. Home-made masks are also quite good.