Bird flu is highly lethal to some animals, but not to others. Scientists want to know why

In the last two years, bird flu has been blamed for the deaths of millions of wild and domestic birds worldwide. It's killed legions of seals and sea lions, wiped out mink farms, and dispatched cats, dogs, skunks, foxes and even a polar bear. But it seems to have hardly touched people.

Bird flu is highly lethal to some animals, but not to others. Scientists want to know why
In the last two years, bird flu has been blamed for the deaths of millions of wild and domestic birds worldwide. It's killed legions of seals and sea lions, wiped out mink farms, and dispatched cats, dogs, skunks, foxes and even a polar bear. But it seems to have hardly touched people.