[Polar bears] have a new deadly challenge facing them: bird flu. It was recently confirmed that a polar bear from northern Alaska has died from the disease.

The current strain of H5N1 influenza has affected a far wider range of species than any previously recorded strain. This has included several mammal species, such as foxes, otters, mink, sea lions and seals (including, for the first time, seals in Antarctica). Cases have been detected in humans, too.