Fun with Microbiology

Last night at D&D Encounters, the DM said something to the effect, "Any bloodied character who ends his or her turn in the sewer water risks exposure to Filth Fever," to which I replied, "Yes!"

My response to everyone's confused looks was, "What?  I like microbiology!"

I like that sort of weird detail; in my Cthulhu Dark Ages game, the home town of Sudleigh used wells because the river water was "sick."  Unsurprisingly, the town upriver is dumping their garbage and human waste into the river.