There are a bunch of other reasons to care about air quality... Like it being a proxy for your risk of a lot of other aborne pathogens (some of which, unlike COVID, you might actually permanently avoid, rather than COVID which is so infectious that measures like this might delay you getting it by a few days but probably not more as a varient sweeps through everyone in your city).

Not all smokers get lung cancer, but I agree it would be funny if you appear so paranoid and then contract covid (though perhaps they have a legitimate reason to be particularly afraid of sars-cov-2, I don't know their age or comorbidities).

Nope. Not yet as of Monday, Nov 14th.

[who just found this discussion of my article... which started long before I finished even getting all the data on the page]