How Much Sleep Do You Have To Lose Before...Wait Is This How The Zombie Apocalypse Begins?

I know...that title was a little on the...okay I admit it, it was mega long - but seriously at this sleep deprived point I am starting to think it is a valid question.
I'm not sure what the exact scenario would be, but maybe the Zombie Apocalypse all starts with one seriously sleep deprived, meat eating mommy. Who gets so tired that she starts to hallucinate (I'm so tired I just typed illuminate 3 times instead of hallucinate).
Anyway, this poor mommy starts to hallucinate and one day whilst she is out walking with the babies she takes a bite out of a delicious looking steak that she sees at the side of the road (she assumes that this must be a dream, and that she must actually be asleep - as otherwise really, who would eat a giant sized tasty steak on the side of the road? It would be kind of yuk...).
Unfortunately, the steak turns out to be a very convincing hallucination and what she actually took a bite out of was an old man with some rare disease that when mixed with a mummy's saliva and stomach acids turns him and her into a zombie... (did i mention that she was rather unlucky). I think the children with her may have some kind of weird immunity... But still if mankind's only hope is 2 children with an aversion to sleep and who are too young to wield a sword...it looks like things will be bad for a while.
Okay, I realize the above is the crazy nonsense of a very sleep deprived mommy - but still I feel the question was worth asking.
Seriously... I really need some sleep. How River and Indigo are still bouncing about, I have no idea?
(I apologize for the rather crazy post).