Well now, it depends. Are these Ob's brethren? If so, there is not a damn thing we can do, may as well give yourself up. Cuz within 30 days, Earth is gone.
I hated that novel. There was no way to survive because literally every living thing became a zombie. Then if you managed to kill a zombie that particular zombie was dead, but all its knowledge awoke in another body and it just kept going.
If it's slow, dumb, Living Dead style, they can be taken out with a pool cue. Not really much to fear there.
It always amazes me how much hate, any more, there is for Romero's classic zombies. To me they've always been more frightening than the fast zombies of the remakes. The slow zombies were more frightening from my perspective because they were able to just blend into the background. The fast zombies just swarmed you and you usually could see (or hear) them coming. The older ones were harder.