Well, then where is the scientific evidence that simple masks reduce chance of spread by an order of magnitude, as described? There is none, because the scienc

Well, then where is the scientific evidence that simple masks reduce chance of spread by an order of magnitude, as described? There is none, because the science hasn't been done. There's a viral JPEG on the internet that claims this, it's just that. If we don't have that evidence, the we don't really know, plain and simple. That's not to say people should stop wearing masks. It's plausible that they help. It's just that we don't know the extent to which they help.