Then, like something from a movie, they join their attackers on the hunt for more victims. His mind races to fill the gap created by the question and immediately the word "zombie" is thrown out by his imagination, but he looks at them with a suspicion that this won't quite do as an explanation.
The now ransacked town surrounding him has been torn apart by this seemingly infected, blood thirsty mob. Each of them carrying wounds similar to his own. Bite marks. Entry points for whatever nefarious entity now controlled them.
He couldn't remember when it happened, when he was bitten and added to their ranks, but he could remember how it felt. The strange pop as the teeth broke through his skin and sank into his flesh.