The level of pandemic risk depends on how widespread H5N1 is in domestic poultry, how often the virus is transmitted to humans, and the concurrent circulation of human influenza viruses.

• 大流行危险的程度取决于H5N1如何在家禽中广泛传播、病毒多久传播给人以及同时发生的人类流感病毒的传播。