at number 19, toxic transplants. joshua hightower needs a new kidney. he's on a list waiting his turn for the life-saving organ. a potential donor dies. joshua gets one of the man's kidneys and then suddenly, instead of getting better, he gets sicker. >> he was throwing up, headaches, had the shakes real bad. sleeping a lot. >> within months joshua is dead, at age 18. a doctor tells his mother he died of rabies. >> and i said, what do you mean rabies? like some foreign branch of rabies? or some kind that is, you know, uncommon or rare? and i said or the kind that you have vaccinate your dog every year for? and he said, jennifer, the kind you vaccinate your dog every year for. >> and just how does this teenager get rabies, a virus that's spread by animals?