I meant to open this thread awhile back, but never did.
Regarding cryptosporidium as mentioned in the linked article, most human beings, if infected, it passes through no harm done. It’s those who are immune supressed, for example, HIV+, it can seriously harm. Cryptosporidium in water all you have to do to access is push the button on a public drinking fountain caused deaths of a number of such individuals, including one HIV+ child, in Wisconsin a while back.
It amazes me what grown people must be told to do, though–Please don’t swim when stuck with diarrhea. Really? A government official must step in and tell people that? Sad.