Victoria police, page-107

I myself believe that masks work to a certain point, but true, the virus will penetrate the mask
from the person wearing it, without any problem (airborne infection - from the recent report in Aust)

But the other thing is you can get infected through the eyes. The eyes are moist and the virus floating
around will just stick to the moist eyeball. This is the easiest way for infection.

(anyway Im a fan of letting the virus play out, ie letting it rip with certain minor restrictions for a couple
or 3 weeks and then bingo the virus dissipates, with same amount of deaths over the long term)