Question

Why did diseases like smallpox affect Indians so badly?

Indians were less robust than Europeans.
Europeans deliberately infected Indians.
Indians had no immunity to European diseases.
Conditions in the Americas were so harsh that Indians and Europeans alike were devastated by disease.

Answer 1

Indians had no immunity to European diseases

This fact was one of the main causes for the decimation of the Native American population. The Indians simply never encountered the European diseases and their bodies had not antibodies to fight them off.

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