Well, one comforting thought is that fowl pox runs its course in three weeks, and doesn't usually cause high mortality (unless it is the wet form, in which case it is more serious).
Mosquitoes are one of the most common carriers of fowl pox, along with flies. All of the books that I've read say to treat the area where the birds live for flies and mosquitoes. This will cut down on the number of birds infected. If only a couple birds are infected, it can be a good idea to separate them, as this may prevent the spread of the disease.
Fowl pox isn't usually dangerous, but it can cause secondary infection. I'd treat with a broad-spectrum antibiotic, such as Oxytetracyline, to prevent such an occurrence.
Scabs and blisters may accumulate so much on the face that the birds can not see to eat and drink. If this occurs, put petroleum jelly on the scabs. This will soften them, and you will be able to pull them off so that the bird can see to eat and drink. Apparently, adding sulphur to the petroleum jelly helps, as it deters insects.
Good luck with your birds! I hope that they all survive the disease.
