YES THE HOMELESS CAMPS! The ones in LA, San Fan, Seattle
....
There may be a hint here:
“Further evidence that common cold coronavirus could protect against COVID-19.
In this paper from Cell, 40-60% of blood samples from 2015-2018 demonstrated T-Cell reactivity to the current disease as a result of previous exposures to common-cold coronavirus. “
https://twitter.com/profshanecrotty/status/1261052353773363200 …
So, maybe there’s some protection by being constantly exposed to colds.
Small test, so not conclusive.