It depends. Covid is a high k disease, a few people end up infecting hundreds in an afternoon, many people fail to infect the spouse they share a bed with. Pa

It depends. Covid is a high k disease, a few people end up infecting hundreds in an afternoon, many people fail to infect the spouse they share a bed with. Partially that's behavior but partially it's people achieving very different peak viral loads as well. The protection factor of 2 or 3 you might get from a surgical mask are going to be useless in some situations but might prevent an infection in others.