According to ESRB, this game contains: Blood and Gore, Strong Violence
Parents: keep your children away from this game. If they ask you why they can't have it, you don't have to play the violence card, you can just tell them you care about the quality of game they play.
Zombie fans looking for the definitive zombie shooter should keep right on doing that.
Deaf and Hard of Hearing gamers will be fine. All instructions are printed onscreen, and there aren't any important audio cues. One might think ravening zombies would make some sound as they approach, but these are surprisingly and frustratingly quiet.