The Walking Dead: The Television Series

[Professor S]

What caused the "outbreak", if there is one, is irrelevant. As Hitchcock would say, it is the "McGuffin". Taking time and effort to explain the cause of the zombie apocalypse would 1) take away from the story and 2) cause inevitable disappointment because what the authors believe caused the event would fail compared to the expectations of the audience.

My big question is: When will they reveal that you don't have to be bitten or be "infected" to turn into a zombie? All you have to do is die of any cause and you end up a walking man-eating corpse. For me, that reveal in the comic was the most chilling of all; the realization that everyone will end up a zombie in the end... they are all The Walking Dead.