If it's any consolation, you wouldn't be fighting real zombies, anyway. Despite what Hollywood says, those things ain't friggin' zombies. Zombies have nothing to do with radiation or viruses or hell spitting things out or what have you. Zombies are mindless undead servants under the thrall of a voodoo master - they do not eat brains. They do not eat anything. They're DEAD. (Sorry, pet peeve. Anyway, a tip - if you ever DO run into some genuine zombies, and their mouths happen to be open a bit, throw some salt into them. If a zombie tastes salt, he remembers he's dead, and heads back to his grave. Word to the wise.)