This last week I've gotten into a discussion with a few people about vaccines and risk. I would highly recommend Wired's assessment of the situation from their last issue.

But it's brought up a lot of thinking about risk. From everything I've read, it would appear that we humans are really really bad about understanding and responding to risk.

Here's an important paragraph from the Wired article:

Today, because the looming risk of childhood death is out of sight, it is also largely out of mind, leading a growing number of Americans to worry about what is in fact a much lesser risk: the ill effects of vaccines. If your newborn gets pertussis, for example, there is a 1 percent chance that the baby will die of pulmonary hypertension or other complications. The risk of dying from the pertussis vaccine, by contrast, is practically nonexistent — in fact, no study has linked DTaP (the three-in-one immunization that protects against diphtheria, tetanus, and pertussis) to death in children. Nobody in the pro-vaccine camp asserts that vaccines are risk-free, but the risks are minute in comparison to the alternative.

But there's a bigger issue to our thinking about risk in terms of our own life.

Did you know, for example, that according to the National Safety Council, that in any given year an American has a 1 in 1,756 chance of dying from "external" forces (meaning accidents, crime, act of nature, botched medical procedure, etc). That doesn't count the big killers: heart disease, cancer, etc, just accidental stuff that can happen to you that is out of your control.

And how those risks balance out aren't intuitive. How often have I heard (or thought) biking to work is dangerous. And yet, the chances of dying in any given year while on a bike are 319,857 to 1, while the chances of dying while in a car are 20,331 to 1. Even being a pedestrian is more dangerous than being on a bike (chance of dying in any given year as a pedestrian: 48,816 to 1).

But it doesn't help to just stay home. You've got a 1 in 15,085 chance of dying in any given year from a fall, and that can happen anywhere.

And can you guess what the least likely way to die as an American is? A fireworks discharge. You have roughly a 1 in 74,126,765 chance of dying from fireworks.

Should make you feel a lot better the next 4th of July, no?