So it's been a while since I heard anything about bird flu, but I stumbled upon an article in the LA Times about a few recent human cases. For a while it seemed like a big media fear mongering, ratings-grubbing fad; then the excitement died off and so did public interest. Bird flu, or H5N1, started as an avian only disease. Influenzas often start off as animal viruses, and then make a trans-species jump to humans. People in close contact with farm animals are usually the first to experience the new flu. The flu virus is incredibly dynamic and constantly evolving, causing the need for newly developed flu vaccines each year.
Though bird flu is currently less pathologically dangerous than something like the Spanish Flu (which caused a horrific pandemic with a hefty mortality rate), no one knows what direction it will take. Without control, it could rapidly mutate into a very scary and contagious human flu.
So what are we doing to keep bird flu at bay? Oddly enough, we're vaccinating chickens! I wonder if chickens have to show their immunization records before they can work at McDonald's... as chicken McNuggets of course.