As you know, I had a combination kidney/pancreas transplant about 9 years ago.
For the first six months following surgery I wasn't allowed to go to casinos -- period. And for the first year following my surgery I had to wear a face mask when playing.
(I also could not eat salads, or vegetables for fruits for the first six months, and had to have my meats cooked well done or at least medium well so there was no blood or cool centers. All this so as not to risk bacteria.)
Now, I'm pretty much like everyone else. I wash my hands regularly, I use a paper towel to open bathroom doors, I avoid restaurants where I don't trust the look and feel of the place.
I am not a smoker. I will avoid smokers. If someone is blowing smoke in my direction I will ask them to stop and I have never had a problem with a smoker who didn't. I like the non smoking craps tables at Bellagio.
Actually, I have found that Caesars has a larger percentage of non smoker than other casinos. Maybe it's the age/income thing that means fewer smokers?
In general, I think there are fewer smokers in casinos than there were five years ago.