If you are in contact with infections substances all day every day you need 99.99999% (I'm pulling this figure outta my ass, but you get the picture) protection

If you are in contact with infections substances all day every day you need 99.99999% (I'm pulling this figure outta my ass, but you get the picture) protection. To bring R0 below 1 you need 75% protection. That's why we saw advice like "just wash your hands" - ultimately inadequate, but it wasn't apriori silly.