A new strain of flu that has the potential to become pandemic has been identified in China by scientists.
It emerged recently and is carried by pigs, but can infect humans, they say.
The researchers are concerned that it could mutate further so that it can spread easily from person to person, and trigger a global outbreak.
They say it has “all the hallmarks” of being highly adapted to infect humans – and needs close monitoring.
As it’s new, people could have little or no immunity to the virus.