When the Europeans travelled to the New World and brought the diseases that wiped out so many Native Americans, why didn’t the local diseases have the same impact on them?

Question

Were the endemic diseases just less severe?

In: Other

Answer 1

Having large cities leads to diseases evolving. Something like Smallpox in a small isolated community would result in either everyone dying or developing antibodies to it pretty quickly. It works different in a large city though. There are people moving to the city fast enough for it to have a constant supply of new people to infect.

European settlers brought these diseases that developed in their major cities. Native Americans had no real equivalent. The largest settlement was maybe 10% as large as London, and it was an outlier.