Nadia Higgins 
Down, Zombie, Down! [PDF ebook] 
Zombie Zappers Book 4

Who let the zombies out? Leo is hurt when Chad starts spending all his time with Jeremy. Only his family’s new dog, Tina, can make him feel better, but she’s been acting funny lately. And she’s not the only one. The Zombie Zappers soon realize Rotfield is facing a rare zombie epidemic. And Leo and the rest of the gang won’t be able to save their town without the help of Chad’s new best friend.