There is no way to kill "all the germs" anywhere. They are part of the
environment, they exist everywhere, it would not be beneficial to kill all
microbes on earth. It is a good idea to wash hands frequently, especially
when in frequent contact with others. As a teacher, I have to remember to
use that "no-water" hand cleaning gel between classes.

If one wanted to spread some kind of medication in a room to kill all germs,
or do anything else, I really doubt that smoke would be a good way to do
that. Any kind of smoke is highly irritating to the eyes, nose, sinuses,
throat, etc. The damage that would be done there would far outweigh any
benefit from "killing all the germs".

Actually, when I was a kid with severe asthma, my mom burned an OTC
preparation in the room, that was supposed to be burned to create smoke,
that was supposed to help the asthma. The main ingredient I believe, was
Belladonna. (I think the name of the product might have been "Asthmador". It
smelled terrible, and I had to sit in a room filled with that smoke, and my
brothers as well, although they didn't have asthma, sharing the bedroom with
me, had to breathe it all night.

I doubt that product is on the market any more, probably banned. Whether or
not that medication might have had some short term benefit in an asthma
attack (I don't recall if it helped), the long term effect of children
having to breathe in any kind of smoke could only be bad. (I think
belladonna has some negative effects in itself.) (Of course, my mother's
intentions were only to help me.)

X---L---?

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