One theory is that even if a face-mask doesn't stop infection completely, by reducing the dosage you get, the virus could develop more slowly and give your body more time to respond so you get milder symptoms vs being blasted with a heavy dose and it getting overwhelmed. This may be why medical staff are hit so hard with it - too much sudden exposure in a short time-period.
That's for airborne transmission. It also prevents you touching your own face which helps prevent the other major method of transmission.
The messaging we were being told that "face-masks don't help" is a lie. The message was really "they damn well do help but we didn't think to stock up enough so we want you to not have them so we can". I understand that healthcare workers need them and should have them. The problem isn't regular people buying them, it's healthcare management not doing their job.
Simon yes yes yes!!! I’ve been saying all along, very much like HIV, the viral load of the person who infects you and the method of infection(ie for example those who contracted it as I.v. Drug user’s via a “bolus “ dose) affected the prognosis of the person who caught it. Ie the stage of the disease in the infected makes a difference to your chance of survival and I’m certain it’s a similar situation with Covid19.
And yes, masks work! We can’t get them but I’ve been ordering my teen’s to wear cotton”bandanas” over their mouth and nose, then carefully removed and boil washed (if you have a dishwasher that will do the trick)
Now the W.H.O. are similarly advising people to use them.