|Agree. I think the key to look for is whether or not a study has been peer-reviewed. At least one recent study (might have been the one from Pfizer re: boosters, but I don't recall for sure) received criticism for not having been peer-reviewed before publicizing. (Naturally, they stand to make lots more money if boosters are needed. I'm glad the CDC is reserving judgment on that until there's more data.)|
My thought at this stage is that no one yet knows for certain whether or not a person who's been vaccinated can still pass the virus on to others. That's probably a very difficult thing to test under standards usually applied to medical studies. My suspicion, though, is that if people can still get infected - even if asymptomatic or with just a mild case - they probably have enough viral load to pass it on to someone else, however unlikely. The closer or more sustained the contact, the greater the chance.
So the amount of viral load, in the surrounding air and even within the body of an infected person, apparently greatly influences chances of infection and maybe even how ill a person gets from it (although I doubt it's quite that simple). I've heard the Delta variant produces a dramatically higher viral load than previous versions, making it so much more contagious. Clearly, that's where masking can make a big difference.
I'm sure we'll continue to learn more and more as time goes on.