Someone will be along with more info soon, I'm sure. Poor Rebel. Dudley had a bad reaction to a parvo vaccine when he was a baby and he had hives, but they were all over...he was covered from nose to tail! I couldn't count them. His little face also swelled up like a balloon. I gave him Benedryl right away and the vet said it actually saved him. I'm thinking it's either the egg or something bit him. Sorry I'm not much help!