That was exceptional and most of our parents are great. We still end up with colds and flu at the start of each school year though. The kids just get exposed to too many micro-varmints and unknowingly bring them to class with them.
Sure...on the other hand, are
they washing hands both before and after class? Sure, we can say that kids are little germ factories, but we need to teach and enforce basic hygiene (hand-washing, not touching hands to face, covering coughs and sneezes, and not training when you're a walking petri dish). If we don't bother to do that, I don't think we can say that it was inevitable. Truth is, if you don't take those precautions, you're not trying to avoid getting sick.