I hate to talk sense, but from a biological perspective it is not possible. If the zombies are decomposing and they have no form of defense mechanism for germs, it means that soft tissues such as the eyes, eardrums, sensory receptors in the nostrils would be the first thing to go. Meaning, they wouldn't be able to see, hear or smell. Another issue is, if they are decomposing, it means that their muscle tissues are also decomposing, meaning they shouldn't be stronger than us. Another issue is, their intestines would be bloated and bacteria will eat them from the inside-out, just like any decomposing body. This would make their digestive system in-operable and they would not be able to digest anything they eat.
I must give the George Romero credit for creating the zombie though. The fact that its a virus gives it a bit of credibility because viruses takes control of other cells in the body so that they can reproduce. Kind of like a zombie.
So to answer your question, do I think there would be a zombie apocalyse? My answer, NO
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I got two buddies who can play COD zombies from dawn till dusk. Walking dead ain't nuthin like that, it has a conversation setup similar to Mass Effect but, but there's a timer so you have to choose the conversation direction carefully. apparently it's meant to go with the TV series. There's a free demo as well
