From the picture, it looks as if this little ones eyes are bugging out a bit. From that and the sore on the top of the head I would say some type of a sinus thing going on. I would treat for that first, Duramycin-10, 1/2 tbls. per gallon of water every 24 hrs., 7-14 days. The other scabs could very well be from fighting and pecking, it doesn't look like Fowl Pox to me. If you are worried about that, you can vaccinate the rest of your birds with Poxine or Chick-N-Pox. I get mine from Jeffers. Fowl Pox is one of those diseases that once you have it, you have it. There is no cure. It is very slow going through a flock so there is time to vaccinate to stop the spread. The dry form usually doesn't cause too many problems, the wet form, internal, is a different story all together. It can and many times will cause the death of the birds that get it. That's why I said earlier, be careful what you wish for.
If it ever does show up in your flock and you are lucky,?, enough to just have the dry form, use Blu-Kote on it. Spray a Q-Tip and paint it on if it is too close to the eyes to just spray it. This helps to keep the virus from spreading by the scabs being injested by the other birds.
