Should we wear face masks when we go outside?

The primary transmission of coronavirus:

The primary transmission is now known to be droplet-based, and we now know that that transmission largely occurs in the first seven days after infection, when people are largely asymptomatic. So that means that if you’re highly infectious, you probably won’t know it. So we should all assume that we are potentially lethal to people around us. The way we are potentially lethal to people around us is when we speak: that’s when these micro droplets get ejected up to six feet.

The reason why does a mask help:

If you’re speaking, and you put a couple of layers of cotton or paper towel in front of your mouth, the droplets go into that and not into the face of the person you’re speaking to. That’s why masks dramatically help reduce the spread of the virus.

It’s like a pitcher and a catcher at a baseball game. And the masks are all about trying to keep the pitcher from pitching the ball. There are more pitchers than we realized, and if we need to all wear masks in order to keep the pitchers from pitching their balls, then so be it.

To protect frontline healthcare workers:

Medical-grade protective gear, such as N95 respirators, should be reserved for frontline healthcare workers.

On April 3, the CDC recommends that the general population wear non-medical masks

On April 3, President Trump announced that the CDC now recommends that the general population wear non-medical masks—meaning fabric that covers one’s face and nose coverings, like bandanas or cut T-shirts—when they must leave their homes to go to places like the grocery store. The measure is voluntary. The mayors of Los Angeles and New York City have already made similar recommendations. In other parts of the country, it’s not voluntary: for example, officials in Laredo, Texas have said they can fine people up to $1,000 when residents do not wear a face covering in public.