I'd imagine there could be an undead apocalypse, but zombies are created by necromancers to serve them as warriors. Unless a HUGE group of necromancers were for some reason angry at the general populace (which would be very weird and make for particularly dumb writing, but heh, zombies right?), and if said group had access to an enormous stockpile of corpses, then a 'localized apocalypse' would be possible. This would've probably been the after-effects should the player had failed the Soiltude questline, as Potema would've tried to reclaim her, technically rightful, place as empress.
Vampires
could also have a large outbreak, but again, it would be a really stupid move for them to do.