A bird flu called H7N9

Across China, the virus that could spark the next pandemic is already circulating. It's a bird flu called H7N9.

What H7N9 can't do-yet-is spread easily from person to person, but experts know that could change. 

The longer the virus spends in humans, the better the chance that it might mutate to become more contagious-and once that happens, it's only a matter of time before it hops a plane out of China and onto foreign soil, where it could spread through the air like wildfire.

The World Is Not Ready for the Next Pandemic
Time Magazine, 4 May 2017