Are you still giving the vitamins? I just wanted to ask, because there is such a thing as selinium poisoning. I think I would back off on that now... Have you tried massaging the neck and gently straightening it as a type of physical therapy? I think I read about somebody doing that with success, it might be worth a try. I am glad that the respiratory symptoms have cleared up! As far as it being contagious, even the common cold for people is contagious before symptoms show, so that doesn't surprise me. A lot of illness are that way, you get infected, start shedding virus, then get symptoms. Most of the time when you get a virus, you don't actually get 'cured', the virus is still there but the symptoms go away. They often reappear when the critter gets stressed (moving, temperature extremes, etc...).
I hope he does a complete recovery, and good job!
I hope he does a complete recovery, and good job!