I actually knew about the possibility to get infected with some sort of salmonella strain from one's tank, didnt know about the other deseases tho.
This is one of the reasons why our tanks should be in perfectly clean conditions not only on the sake of fish health but ours.
I have siphoned my tanks many times and to start siphoning I always suck one side of the hose while the other is in the tank and one time I got careless and this very dirty water from my turtles tank got into my mouth...lol! -If you have kept turtles you know what kind of dirty water we are talking about, literally ****-
I spited the water and went to the bathroom washed my teeth very well, I rinsed my mouth and gargled with listerine, after that I drank some tequila shoots to kill any possible bacterial remain....lol!
Furtunately nothing bad happened.