Oh honey, you are preaching to the choir! I have no clue what to do. My son has always been on the receiving end of bites too. And never by the same child. I think my kid is a toy snatcher but I don't know. Let me know what YOU find out! The bug spray is a really good idea though! I'm going to try that!
By the way, if he continues getting bit, you should really complain to the teacher and then to the director. They may not be watching them closely enough