The Signal and the Noise: Why So Many Predictions Fail-but Some Don't

by Nate Silver

The perfect incubator for the swine flu, then, would be a region in which each of three conditions held: It would be a place where humans and pigs lived in close proximity—that is, somewhere where pork was a staple of the diet. It would be a place near the ocean where pigs and seafaring birds might intermingle. And it would probably be somewhere in the developing world, where poverty produced lower levels of hygiene and sanitation, allowing animal viruses to be transmitted to humans more easily. This mix almost perfectly describes the conditions found in Southeast Asian countries like China, Indonesia, Thailand, and Vietnam (China alone is home to about half the world’s pigs34). These countries are very often the source for the flu, both the annual strains and the more unusual varieties that can potentially become global pandemics.*

But. It can start anywhere. At any time.