Why can’t you just say “bless you”?
Why say it at all? The custom of saying "god bless you", and, of late, "bless you", after a sneeze comes from various superstitions regarding the need for a blessing from god when sneezing. Personally, I am irritated by people who say it when I sneeze, and I'd prefer them to ignore it and move on. It's caused by dust, allergies or a virus, not evil spirits.
Watch out for demon of nasal irritants.
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