Originally Posted by BlankCanvasDJ
A strong airborne virus can spread pretty quickly.
I agree with TheNNerdGamer, I don't think zombie bites and the zombie virus are actually related at all. Zombie bites just happen to be lethal, allowing the virus to do its work.
I'd go further to say that the zombie virus remains dormant because our immune systems are still strong at that point and viruses of other types have been known to do that.
The zombie bite acts like an immune system blocker, like AIDS or a list of other immunodeficiency diseases. The bite lowers your immune system and everything around you just kills you. The zombie virus only activates upon death.