A型流行性感冒病毒的自然宿主是世界上的水栖禽鸟类〔1〕,在禽鸟中病毒与其自然宿主之间处于一种平衡状态,并可周期性地传播到其他宿主(包括哺乳动物),引起短暂感染和偶尔死亡,持续感染的情况较少见。1997年以来,当H5N1病毒首次在香港被传播到人并导致6人死亡时,便发现禽流感病 The natural host of influenza A viruses is the world’s waterfowl bird [1], which is in a state of balance between the virus and its natural host in birds and can periodically spread to other hosts (including breastfeeding Animals), causing transient infections and occasional deaths, and persistent infections are less common. Since 1997, when the H5N1 virus was first spread to people in Hong Kong and resulted in the death of 6 people, it was discovered that bird flu