So, just how "hazardous" can a tank full of poo be?

Went to a very large eyedoctor clinic last month with 30 - 40 patients in the lobby at a time. The access to the toilet facility across the public area was controlled by checking out a key on a lanyard. Wife is very carefull about wipes after touching the door handles and the toilet sink facilities but I had to caution her not to put the lanyard around her neck.

its everywhere..........