Not to be argumentive but this is from the Merck vet manual, I wonder which is correct? Infectious coryza is an acute respiratory disease of chickens characterized by nasal discharge, sneezing, and swelling of the face under the eyes. It is distributed worldwide. The disease is seen only in chickens; reports of the disease in quail and pheasants probably describe a similar disease that is caused by a different etiologic agent.
In developed countries such as the USA, the disease is seen primarily in pullets and layers and occasionally in broilers. In the USA, it is most prevalent in commercial flocks in California and the southeast, although northeastern USA has recently experienced significant outbreaks. In developing countries, the disease often is seen in very young chicks, even as young as 3 wk of age. Poor biosecurity, poor environment, and the stress of other diseases are probably the main reasons why infectious coryza is more of a problem in developing countries. The disease has no public health significance
In developed countries such as the USA, the disease is seen primarily in pullets and layers and occasionally in broilers. In the USA, it is most prevalent in commercial flocks in California and the southeast, although northeastern USA has recently experienced significant outbreaks. In developing countries, the disease often is seen in very young chicks, even as young as 3 wk of age. Poor biosecurity, poor environment, and the stress of other diseases are probably the main reasons why infectious coryza is more of a problem in developing countries. The disease has no public health significance
