This movie is really bad, trying to create scientific explanations for zombies always ends up taking away credibility from the history of the movie. There are so many things i could point about the movie that i could almost write a book on how much the movie sucks. For instance, there were like 50 people on the plane, they killed like 100 and they kept coming, apparently the "virus" gives hepatic complications because everybody had yellow eyes, also the virus makes people roar like lions or something, and the virus not only regenerates tissue as it also gives superhuman strength, not to mention that this virus messes up peoples hair. It's also important to notice that if you shoot someone with a pistol (probably only happens on planes) that person is kicked back in the air. Remember that if you are escorting a prisoner on a plane and you loose him, always look inside the drawers and cabinets the size of a bottle, you never know where those bastards are going to hide. And if by any chance you can land a plane full of zombies against a mountain and survive (happens all the time), after watching dozens of people being killed, just walk away from the plane, watching the sunrise and making jokes about dating the flight attendant. :)