The chicken pox... a virus almost every single one of us have had... Parents would make their children play with other kids who had it just so they could get it over a done with (once you get it you cannot get it again)... the same as I understand with avian pox, the bird form of "chicken" pox
Out little hen named Tiny who was traded to us for our rooster Happy was in confinement for 2 1/2 weeks outta the 4 weeks you are supposed to keep them in when she came down the the avian pox, first her comb got little blisters and crud on it, so we cleaned it off then she developed little sores and warty looking things on her toes, waddle, and beak.
I looked into every chicken disease I could find online before settling on this diagnosis... reduced egg laying, stress, the bumps and sores, the lack of eating... it all fit.
Sadly there is no real cure, we have started adding apple cider vinegar to her water (and the others) as well, and cleaning her sores with rubbing alcohol which some say make them heal faster.
She has the dry form which shows as warts and sores on the parts of the body not covered in feathers, the other "wet" form, creates sores in the mouth and eyes and can cause is some SEVERE cases death or eye loss.
Avian pox is spread by mosquitoes which in Florida is a big problem, so I am glad to learn about this now.
She will remain in quarantine until it is all gone and there are NO sores left.
Poor little Tiny!!!