Flu Deaths

What is with this string of the flu? Watching the news tonight (I was at my parents house, so it was on instead of Friends) they were reporting the newest flu death, a firefighter. This is no longer the string of young children, or elderly people, whose immune systems aren't up to par that have died to this string. This is a perfectly healthy firefighter.

Trust me, I don't get scared about these things. I'm not about to go buy a bio-hazard kit, or submit to a sky is falling mentality, but what happens to a virus strain that makes it this much more powerful than past viruses?