From a former Public Health weenie - there's a song by Tom Lehrer called something like "I Got it from Agnes," but I can't find it in the DB, so I may have the wrong title. I seem to recall it's in his book, and I seem to recall I have the book...somewhere.

I can't believe nobody's mentioned this, to the tune of "Yesterday," but I can't find it in the DB either. I'm sure there are more verses:

leprosy
All my parts are falling off of me
I'm not half the man I used to be
Oh, I think I have leprosy
Why my nose had to go I don't know
It didn't say
...(can't remember)...
Syphilis
Now it even hurts to take a piss (poetic license - not technically correct)
Oh, how did I end up like this
I think I have syphilis...

And I used to sing this when I was learning how to do fecal exams in a school for vet technicians. To the tune of "Feelings" -
Feces, nothing more than feces...