(Well... we'll know in a week or so... but...)
The last great flu pandemic to hit the world was in 1918. That flu killed 2.5% of all people it infected. This new swine flu is killing 6%.
So why not worry?
Think about 1918. There were no anti-flu medicines. There were no widely-available face masks. There were no quick diagnostic tests. There were no governmental early warning systems. There was no widespread knowledge of how to avoid infection, or quick access to medical personnel if one did have an infection.
Today, people — even in the relatively poor country of Mexico — are being screened weeks earlier, preventative measures are being taken, quarantines are being put up when they can still be effective, and information about this situation and how to prevent it is a knowledge that pretty much everybody on the planet now possesses. We are a cleaner and healthier race than we were 90 years ago, and the immediacy and quality of our medical care is vastly improved in even the poorest corners of the planet. The United States alone handles millions of flu cases per year, and while the swine flu is a specially bad version of the flu, it is still the flu.
Can a disease still come along that will again wipe 40 million people? Possibly... but if it does, it will be something new and unexpected to which the tried and true methods of infection avoidance prove to be ineffective.
A little swine flu humor added in for levity's sake: