"Pox Americana" is a very scary book, in its own way. What it covers is the Smallpox epidemic that spread through North America between 1775 and 1782. I've read about half; the first section covers the American Revolution- but from the perspective of the war as a disease spreader. Consider: American soldiers (British soldiers and their mercenaries tended to have immunity) were vulnerable to the disease, and were traveling over a much wider area than they ever had. The war caused civilian displacement as well - and both things spread the Pox. It looks like the native population took it hardest, and the author gives two reasons:

• Virtually no immunity in the population
• A population that was far more genetically homogeneous than the European immigrants

The latter problem seems to have been severe - the Pox spread between unrelated natives as easily as it did within a European family. Indian villages ended up having death rates of 50% and more.

It only gets worse in the part of the book covering what was then Spanish North America. Traveling missionaries and traders spread disease out of Mexico City and New Orleans, all the way up through the Pacific northwest. Evidence for the suffering there is fragmentary; there really aren't written records. From what little survives, it sounds like some areas ended up with as much as a 90% loss of population - particularly in the Spanish mining camps, where the natives were already being abused.

I'm in the middle of a section that covers the Canadian interior - disease spread there through the fur trading network that had spread. The British and French traded with the natives, who in turn often acted as middlemen to other tribes. It sounds like the Cree indians of the north suffered near annihilation.

This is scary stuff, and makes me realize how lucky we are that Smallpox has been eradicated. It also makes me worry about the potential for an avian flu pandemic - a bad enough virus with the kind of long incubation period that Smallpox had (up to 2 weeks) could wreak havoc on a tremendous scale.