A friend of mine had it several years ago and the state said she needed to get rid of all birds for at least 100 days but she let it go too long. I think it is reportable in some areas. I hope I am wrong but you must err on the side of caution.
Most books recommend culling all sniffles, sneeze rs and coughers. Emotions aside I would cull to protect the healthy. I have a small fortune in chickens and cannot take the risk. Some diseases are very difficult to totally eradicate, infectious laryngotracheitis is what I think it is, your...