My flock is not free of hateful dry pox yet, but all new cases seem very mild and clear up quick. I had planned in mid February to get another batch of chicks (summer here so great for raising outdoors). Their pen and coop has dry pox scabs in it,. The coop I can clean but the pen is grassy dirt under a tree so I've no idea how to sterilize it. I think I read on one of the looooong pox threads that it takes 3 months for the virus to die....I'm kinda hoping I'm wrong.