This is actually the interesting answer to a question I heard posed a while back. Diseases killed out over 90% of Americas indian popluations whereas europe’s black death only killed 30-50% of europe’s popluation. Why the difference? the reason is that this was the black death’s second appearance in europe —so the europeans had developed some immunity. the americas indians had no immunity at all.
Yup, and not just The Plague. It would be interesting to look at the historical/ancient epidemics prior to 1492 to see if these correlate to the sudden population collapses documented in PreColumbian America.