here in the u.s. i have never heard of anyone being bitten by a fox while fishing, in my opinion the fox had something wrong with it, if it attacked someone. perhaps a disease such as distemper or rabies. or was starving and wanted some bit of food. where i fish there are alot of raccoons, they have very little fear of humans as they are not hunted in this particular area. they will come up and try to steal food or bait, and can get aggressive if they dont get what they want. around the paylakes here there are usually rats around and these i beleive are the biggest danger, due to there being a larger number of them.