This is really enormous stuff, from a Wall Street Journal article from yesterday. Thanks to engineerlite for sending it along to me. What we know about masks and distancing is not quite overturned but it is quite different than expected. The news is both worse and better, in that 6-foot distancing and even cumulative time of 15 minutes is not the real standard after all, and that masks turn out to be important, but not terribly valuable as a strategy in isolation.
The NFL was able to create data that just doesn't exist anywhere else. They are able to keep very close tabs on where their players and staff are, because they are paying them big money and they do NOT want games to be canceled, because it costs everyone a fortune. They test much more frequently. For them, it's not just the physical danger to their personnel. They don't have nursing home or assisted living populations. But offensive linemen do tend to be (often temporarily) obese, and there are older ex-players among the coaches and staff. Yet even more, the PR value of appearing safe is enormous to them - or more exactly, not appearing unsafe and reckless. It's not the same as paying college students $15 or asking thousands of people questions of where they have been in the last few weeks and who they have seen. I won't comment much, mostly just direct you to the article.
"The NFL was slowly discovering something far deeper: a core tenet of Covid-19 transmission wisdom—how to define when individuals are in “close contact”—was just wrong. ""It also wasn’t simply time. It was distance, too. The virus, in some instances, traveled farther than six feet—especially in small, poorly ventilated areas. And masks, more than the duration of contact, seemed to matter a lot.""“It goes back to those four basic things we talked about in the paper with cumulative time, distance, ventilation and masks. If you think about those four factors as being four different quadrants, if you’re failing in two or more of those, then that’s going to become a high risk for a transmission,” Sills said. (italics mine.)
It does begin to answer some questions. Why do some studies show that masks matter a lot and others show they don't matter much at all? Why does distancing matter deeply and not matter?