Special types of bacteria is cultured for it, but the bad bacteria and molds that can make you sick, those are not used. And the bacteria would only escape if there was cross-contamination since the few times mold and such are made is via being dipped or rubbed in specially grown for that purpose.
Cheeses CAN, however, mold if left too long if there's not a proper rind produced. Depending on conditions.
Here, here's some interesting info on it.
RE: Challenge #03798-J145: Let Them Eat Cheese