Bird flu: how serious is it really?

After 133 known US human cases, there was finally a death this weekend. A Canadian teen went from pink eye to life support in 4 days, and a researcher says we're at Defcon 1. How real is it?

For now, the risk to people remains low, but the longer it lingers, researchers become more concerned about the possible mutations that could make it easier to transmit among humans and have a greater impact on human health. In this post and another, I’ve tried to put together information from, and links to, multiple sources.

What is it? What are the sy…