it's beaver fever isn't it? or rather, what causes beaver fever if there's too much of it?
Yah, it's the protozoan that causes diarrhea and other rhea's, extreme gas, foul smelling gas(or perhaps more foul) and a host of other symptoms.
It affects more than just humans, also cats, dogs, cows and sheep.
Unfortunately, because it is Eukaryotic like us, the drugs also have crappy side effects.