Oh, it can already hit people. Fatality rates are stunning- right up there with Spanish Influenza. This stuff could quite possibly kill 1 in 10 people who catch it. Which, if it hits a couple metropolitan areas, means it can eventually infect every developed nation in the world. Figure that there are a few immune to it, and a few that'll get EXTREMELY lucky, the conservative estimates are that this "bird flu" could kill hundreds of millions of people.
On the plus side, it frees up some real estate. It'll also be a natural self-correction of the human race. No matter what we claim, we're not yet above natural law. All-in-all, we're getting screwed in this deal.
