It is well known that the European colonists brought many infectious diseases to the Americas, and that these had a deadly effect on the native populations, because they had no immunity to them. Were there any local infectious diseases to which the colonists were not immune? I’ve never heard of such. I’m not aware that the colonists suffered any epidemics, or that they brought any new and unusual diseases back to Europe.Why not? Is this merely an accident of history, that there were no infectious diseases in the Americas which did not already exist in Eurasia? Or is there some explanation?
The number of diseases that travelled in the other direction was far higher. This can be attributed to the facts that the old world had a much wider area of commerce and a much wider variety of livestock, so that the Europeans were already living with a very large number of contagious diseases prior to contact with the new world, whereas the first Americans (i.e. indigenous peoples) were living with relatively few.
