This comic is, the zombie trope perfected.
In classical zombie moives be it the Walking Dead, or world war z.
every scenario I can think of, humans win.
For example,in twd, they are slow, they are basically dumber than a housecat, can be manipulated, and they will be gone in at most 3 years, because of decomposition.
Even the fast, and not dead zombies like in the ones in world war z or I am legend, they are basically wild animals That can replicate themselves with bites etc.
Even in that scenario, humans can protect themselves in some pocket cities or civilizations, and wait out for beasts to die from hunger. (7 billion mammals can not sustain themselves in normal conditions.) and they cannot reproduce normally. So just wait 30 years and you are set.
But dude. Crossed ARE vicious. (Still humans would come up victorious in the long term but still.)