Colonisation and novel disease transmission

[ChevronB19]

According both to general knowledge, and more specifically an episode of ‘In our time’ I was listening to, the colonisation of the americas by the Europeans wiped out a huge proportion of the native population (apparently up to 90-95%), as the native population had never been exposed to European diseases.

Why didn’t it work in reverse? Ok, to begin with, there were only a few conquistadors from memory, but surely some were exposed to diseases from the americas and subsequently returned home, (potentially) introducing those diseases to Europe?

[ChevronB19]

TwigtheWonderkid said:

For anyone interested in this kind of thing, I'd recommend :

Bought, thanks for the tip. Another one to add to the ever growing ‘to read’ pile!

[ChevronB19]

I can buy that, but even if you restrict the assumption to conquistadors who were over there, and ill ones didn’t make it back to infect the ‘old world’, did 90-95% of the conquistadors die from exposure to novel ‘New World’ diseases? Obviously the numbers would be massively lower.