Every disease has a level genetic pre-disposition, and obvious some demographics are harder hit than others.
While browsing the COVID maps, I noticed one strange thing. It seems that a lot of counties that are highly populated by Scotch-Irish (good bit of my ancestry) VA, WV, NC, TN, KY, AR seem to be less hit than others. That may be randomness, but I think 300 years of moonshine has had a side benefit.
LOL! Mountain folk... and no surprise... though maybe not just likker.
Hillbillies are separate from town... don't go in too often. Grow their own food, so not going to the grocery store... Divorced from others, even among themselves, separation between families/farms...
AND moonshine... and mountain medicine.
You'll find the same thing in the Rockies.