So far, this strain of avian flu appears to have been transmitted only through contact with live poultry, but there’s always a fear it will mutate and start passing between humans. That’s what really scares experts: the possibility of a sudden change that triggers faster spread between humans and leads to a pandemic.
A disease doesn’t count as a pandemic until it spreads worldwide – Ebola killed more than 11,000 people across West Africa before it was brought under control, and that was just an epidemic. The most modern pandemics include the Spanish influenza, circa 1918 (as many as 50 million killed), and HIV/AIDS (35 million dead).
As Chinese officials attempt to stem the latest bird flu outbreak, global public health officials are racing to get ahead of what they call the next “big one”: a disease that will kill tens of millions. It’s all about preparedness, and a large part of that is spotting outbreaks early, so action can be taken to contain any situation before it spirals out of control.
It’s anyone’s guess when and where the next major epidemic – or pandemic – might emerge. It could be a mutated version of avian flu, or perhaps something completely unseen before, like the mysterious illness with Ebola-like symptoms that struck out of the blue in South Sudan last year.
Here are a few more possibilities worth keeping an eye on: