The smell hit first. There's a stench to an outbreak site that you never find anywhere else. Scientists have been trying for years to determine why it is that we can smell the infection even when it's been declared safely dead, and they've been forced to conclude that it's the same viral sense that lets zombies recognise each other, just acting on a smaller scale. Zombies don't try to kill other zombies on sight unless they haven't had anything to eat in weeks; the living can tell where an outbreak started. It's probably another handy function of the virus slumbering in our own bodies - not that anyone can say for sure. No one has ever been able to put the smell into words. Not really. It smells like death. Everything in your body says 'run'. And, like idiots, we didn't.