OldnGrounded #22 Spot on. Can't say much more.
Most folk know a virus is very small. It used to be called 'Non filterable'. This came from finding unglazed porcelain could filter bacteria, but let the virus pass.
"Most viral infection is via contagious transmission." Odd statement, but in a publication c 20 years ago. But it's the airborne droplets that get you.
Eyes are an open door for virus laden droplets. Tears have an antibiotic on one or more of their seven layers, but no use at all for the virus which will spread over the eye in seconds.
Some people create a storm of droplets when speaking - easily visible in front of a daytime window. Doctor's waiting rooms are often filled with people that think putting a fist in front of their silly faces will protect the world. We could empty a zillion hospital beds if only people would carry a mini-towel and blast into that. It could become de rigueur. In the meantime, masks will protect (some) others.