A puzzle I've never asked about before...

[seawasp]

... most of us already know that the majority of the deaths of Native Americans, at least in the first decades of contact, were due to European diseases sweeping like a pustulant wildfire through the unprotected populations. As the Native American populations had been out of contact with Europe and Asia for many thousands of years, they'd never had any reason to develop immunity to things like smallpox, measles, etc., and so what were bad-but-often-survivable diseases to the Europeans became 99% fatal plagues for them.

What I always wondered was this: The same separation existed on the other side, so why weren't all the Europeans wiped out from various American diseases that THEY had no immunity to? Why would Europe have developed natural bioweapons, so to speak, and not the native populations of the Americas?

Comments

[chuk-g.livejournal.com]

Populations in Europe etc. were much higher density, which was sort of a breeding ground for 'superbugs'. I'd have to check but I think there were at least a few conditions that went the other way. Some theorists suggest syphilis may have been spread from the Americas to Europe.
http://en.wikipedia.org/wiki/Columbian_Exchange has a bit more info and some links to follow.