if you take an injured/sick wild animal to a vets they are, i believe required treat it (im not sure if they would try to treat a wild rabbit (ie. unvacinated and without charge) with myxi but at least he would die without pain).
just remeber if you catch him to immediatly out your clothing straight through the wash and have a shower your self befor you go anywhere near your own rabbits. (dont forget to disinfect the carrier)