That's why I use Gesundheit! I had German grandparents so I have to thank them for teaching that one word so I could at least avoid the other.
Oh yeah - that's one of my favourite stories.
In the time of the plague, when there was very little in the way of medical care, one of the first signs of infection in people was a sneeze. Of course, sneezes happened for many reasons, but they also happened when you were getting sick with the plague. So if you were hanging out with your mate, and they sneezed, I imagine the blood would rush from your head as you realised he'd be gone in a week, and various forms of 'health' or 'bless you' would utter forth. The bless you part, so the story goes, was because some believed the plague was caused by demons in your blood. Medieval folks, such a laugh.
Anyway, we get another popular part of kiddie culture from that story:
Ring o'ring o'Rosie
A pocket full of posies (flowers, which ppl carried around to mask the smell of death)
A'tissue! A'tissue! (See above paragraph)
We all fall down. (Glum, huh?)
As for gesundheit, the Afrikaans has a derivative: Gesondheid. It literally translates as health. Or the state of being healthy. Like 'apartheid' was the state of being apart.