As I understand it, C19 is spread via droplets. CDC says "These droplets can land in the mouths or noses of people who are nearby or possibly be inhaled into the lungs":
https://www.cdc.gov/coronavirus/2019-ncov/prepare/transmission.html
What if we all were wearing masks? How much would that reduce the droplets? Maybe enough so we stop the exponential infection growth?
Since it is also not totally clear if the hands and the eyes play a role in the transmission - how about gloves and goggles?