PANDEMIC PHASES
Click on the numbers below to read pandemic phases
No viruses circulating among animals have been reported to cause infections in humans.
An animal influenza virus circulating among animals is known to have caused infection in humans, and is therefore considered a potential pandemic threat.
An animal or human-animal influenza reassortant virus has caused sporadic cases but has not resulted in sustained human-to-human transmission.
Verified human-to-human transmission of an animal or human-animal influenza reassortant virus causing sustained “community-level outbreaks.”
Human-to-human spread of the virus into at least two countries in one WHO region. Strong signal that a pandemic is imminent.
Sustained community level outbreaks in at least one other country in a different WHO region. Global pandemic is under way.Click here to read full description of the phases