

It was already spreading from mammal to mammal. IRC there was that Mink farm last year and I think seals too. There were also cases of H5N1 jumping from birds to humans.
Given H5N1 can make the jump from birds to mammals(including humans), and from mammals to mammals, it’s not a huge shock that it’s made the jump to humans from other mammals.
H1N1 killed 50-100 million people, so the danger has always been there, and scientists have been warning about it for decades. For example, here’s a journal article from almost twenty years ago discussing this scenario:
And according to the promotional video, it will pleasure you with a special dance.