I know that run I did, it was initially isolated "the lab", but after the runners were double crossed and trapped in the lab, it got released into the local environment when they escaped.
In the end they had a full outbreak on their hands that devastated an entire miniature sprawl area. It was pretty much a blatant resident evil rip off, but my players still had a damn good time. Two of them go contaminated by the end of it, one ended up becoming mindless and getting TKed, the other ended up being completely aware and almost better than he was before other than the whole blindness factor. He almost got TKed, but managed to talk them out of it since he wasn't a slobbering fool trying to mindlessly eat them.