Avian influenza virus (AIV), disseminated throughout the world by migratory birds, is the pathogen that can cause avian influenza which was considered as the A type severe epidemic disease by OIE.

• 禽流感(Avian influenza, AI)是由A型流感病毒属的禽流感病毒引起的禽类的一种烈性传染病，特别是高致病性禽流感（Highly Pathogenic Avian Influenza，HPAI），一旦爆发，将会给中国和世界各国养禽业造成相当严重的经济损失；