The guy who swam through his Sheep Dip was certainly free of Ticks ! I guess it would have washed off the Flu' thing as well.
As to Smoking, I did wonder when I heard that smokers seemed less affected, that if their Lungs are full of Gunk and Gunge the 'rona Virus may not be able to latch on so easily ? Who knows ?
The danger is that a Smoker having a good cough up, not knowing the Virus has entered his or her body, will presumably expel more of the Virus than usually in to the Air.