What is a pandemic?
A pandemic may occur when three conditions have been met: a new influenza virus subtype emerges; it infects humans causing serious illness; and it spreads easily and sustainably among humans.
The H5N1 virus meets the first two conditions.
The risk that it will acquire the ability to have efficient and sustained human-to-human transmission is present as long as opportunities for human infections occur.
These opportunities will persist as long as the virus continues to circulate in domestic birds, perhaps for years to come.