Just got back from the vet today who confirmed a case of dry pox (no wet, whew!) in our favorite hen. Before my conversation with the vet, I didn't understand why you would need or want to isolate an affected chicken from the rest of the flock, since the same mosquitoes that spread the disease to the affected bird probably bit the rest of your flock, too (or will, with time). The vet explained two good reasons to me why you'd want to do this. First of all, a bird with avian pox may not be feeling her usual self, and the other hens notice this and tend to capitalize on it. Hens lower on the pecking order may see this as their opportunity to move on up past the affected bird, which is stressful for the bird at a time when her immune system is already occupied with the pox virus. Secondly, the vet pointed out that the pox scabs are contagious, even after they've fallen off. Another bird who pecks a scab either on another chicken or from the ground is more likely to get lesions in its throat that way, and then the dreaded wet pox. Before this explanation, I was wondering how a bird could get lesions down there, since it isn't likely that a mosquito would fly down a bird's gullet. Now I know. So I'm isolating my bird.