Infectious coryza (IC) is caused by the bacteria Avibacterium paragallinarum. Both broiler chickens and laying hens from all age groups are susceptible, but the disease is more common and lasts longer in older birds. IC affects mainly the upper respiratory tract and has the potential to cause a marked reduction in egg production and poor performance. The incidence of IC has increased in recent years, with more complicated clinical signs and higher mortality rates reported, representing an important threat to animal welfare and egg production. It is important to get familiar with the disease for early detection and intervention. Check out the attached link for more information.