[strogonoff]

I think “very effective” is a subjective turn of phrase and no self-respecting org would use it in official communication.

That said, I believe it is settled that airborne transmission happens via saliva droplets, and a properly worn, clean mask is great at stopping those from traveling further than your face (physics) without harming your own health.

Also, I believe it is wrong to equate WHO, CDC messaging with “scientists”. Those organizations are careful not to make specific claims that masks are great at preventing the spread, since a mask is pointless if it’s not a suitable mask (e.g., lets large enough particles through) or is worn badly, since human error is unavoidable, a dirty mask is actively dangerous to the wearer, and over-reliance on improperly worn masks could result in a disaster.

Does it mean we shouldn’t bother deploying our individual common sense in equipping masks? That we wouldn’t make a positive difference to the spread by wearing a good mask properly? I disagree.

Also, having been to crowded subway trains of Seoul recently, I question the claim that Russian cities are somehow crowded enough to render masks useless.