Avian pox is a virus, so there is no medicine that you can give to help them with it. But I have some solutions that will help you to get your flock back into shape.
First, on all the scabs, dot each one with a q-tip very wet with iodine. Betadine is great for this. Not diluted. While the scabs are caused by virus, sometimes secondary bacterial infections can set in which is why we use the antibiotic iodine. On clusters, use iodine first, let dry, and then use neosporin ointment as it will melt with the bird's body heat and continuously treat the sore.
Second, when the sores cluster around the eye, the mouth, etc things get tricky. You will want to buy a little tube of either Terramycin ophthalmic (eye) ointment from the feedstore, or Chloramphenicol ointment. Clean the eye carefully and gently using sterile saline wash for eyes from the drugstore. Wait 10 minutes. Then use the ophthalmic ointment on the sores. If you can open the lid and treat the eye, do so. Are both eyes effected? You might want to use an actual antibiotic for that one (say a penicillin injection) now before things get worse with it for the secondary wound-type infection. Do not use the 'mycins or foil packages from the feedstore as theyre not the right type of antibiotic. You want a 'cillin (preferably injected) or Baytril from a vet (last ditch effort).
Third, as all your birds have had their immune systems challenged, now is the time for ultimate nutrition. They can all get vitamins/minerals in their water, yogurt as a daily treat, perhaps a little extra protein (eggs) to facilitate healing. Open all birds' beaks to rule out wet pox, the cheesy exudate in the inside of the beaks. If you see any of that, please let us know.
How old are the birds by the way?