Learning more about how masks help

Several studies about masks have tried to determine just how effective they are and what types work best.

To prevent droplets from the nose and mouth from dispersing, homemade cloth face masks likely need a minimum of two layers, and preferably three, according to a video case study published online in the journal Thorax.

Several types of material have been suggested, but based on little or no evidence about how well they work. So a team of Australian researchers compared the effectiveness of single- and double-layer cloth face coverings with a three-ply surgical face mask at reducing droplet spread.

The researchers really wanted to make two points: first, that something is probably better than nothing; and second, a two-layer mask is significantly better than a one-layer mask. And a surgical mask may be even a little better than that.

But none of these masks are perfect, so as a result -- even if you're wearing a surgical mask -- there might be viral spread around the layers of those masks.

We know part of the reason masks became such an important tool is that people can spread this even when they're asymptomatic. It means that masks become crucial whenever you are out and about, even if you feel healthy.

But we still need to maintain physical distance from people, even if you're wearing masks. If you start to layer these things in -- the physical distance, the hand washing and the masking -- it can go a long way to prevent the virus from spreading.