I remember back in elementary school (oh so long ago), there was a lice outbreak, I got it and gave it to my parents and grandparents.
Besides the lice, the only other thing I caught in school was Whooping cough. I know exactly how I contracted it. We were not allowed to bring water bottles to school so the drinking foundation was the only option. The foundations were nasty, hardly ever clean. Now the stupid kids would put lips on the spout, for the water would just barely spurt out 3 inches. Needless to say a good handful got sick.