https://www.youtube.com/watch?v=kFxksNcLfcA
I have a friend who studies the history of plagues; was telling me last summer that smokers were viewed as more immune to historical plagues. I never asked him for detailed evidence, as it was one of those conversations you have on the balcony over a smoke. I enjoy entertaining wacky ideas, and figured smokers might be fumigating the fleas, or in the case of pneumonic plague, filtering the air. Never thought of the nicotinic hypothesis. Never really took it real seriously; taking it seriously now. The evidence is pretty overwhelming. A lot of people are going to lose their freaking minds over this, as anti-smoker posturing has become a sort of substitute morality among the upper middle classes (really it's just social class shitting on poor people).
Of course, nicotine is known to statistically significantly reduce the risk of Parkinson's disease, so it wouldn't be the first example of something like this.
https://www.reddit.com/r/COVID19/comments/faluhv/an_exhausti...
https://www.medrxiv.org/content/10.1101/2020.04.13.20063669v...
https://www.qeios.com/read/article/561