OK, I know that you don't live under a rock, so you've hear about "avian influenza", better known as "bird flu". If you haven't, here's one of the better sources I know for information (click on "What's New" for the latest info).
It seems that the US government has been watching the situation as well, although from the amount they've talked about it, you'd never know. Well, it seems they're talking now:
The federal authorities are preparing to face a possible avian flu pandemic in the United States by contemplating a worst-case scenario, under which more than 92 million people will become ill in the space of four months...
92 million? Well, that's about a third of the population of the US. Think of it in these terms--imagine 1/3 of the employees where you work out sick at one time, and some other portion out either caring for them or because they've decided they're going to stay home so they don't get sick. So let's make it 1/2 of the people where you work are out.
How long could your company function with only 1/2 its employees? How long can any company function like that?
Probably just long enough for the economy to collapse. You might want to buy some more beans and bullets soon.