It is very rare that a bird would have rabies, so I doubt it's that. I would find a box large enough for the bird to walk around in, along with an old towel lining the bottom. If you can, get another towel and rap the little guy in it. Next part is tricky, find something to keep the box warm but not hot, should be like skin warm. I used a heating pad on warm once for this same reason, but a desk lamp will work too. K so next you have to put him somewhere he wont be bothered but you can still check on him like a garage or laundry room or even a spare room no one uses. Put food and a small dish of water in with him and something to cover the box, I used a thin cloth that I tucked under some books next to the box, that way I could check on the little thing without removing the lid. Note on using a desk lamp to warm animals, you have to turn it off at night so they can sleep. Sometimes all they need is some R&R to get back on their feet.
