While Europeans and Asians were affected by the Eurasian diseases, their endemic status in those
continents over centuries caused many people to
acquire immunity. By contrast, "Old World" diseases had
a devastating impact on Native American populations
because they had no natural immunity to the new
diseases. The smallpox epidemics are believed to have
resulted in the largest death tolls among Native
Americans, surpassing any wars and far exceeding the
loss of life due to the Black Death.
Alfred W. Crosby
"The Columbian Exchange"
The high instance of disease spread from Europeans to
American Indian populations
was studied by European physicians and led to better
understanding of the behavior of communicable
disease.
drove surviving tribes to ally with each other to
strengthen their resistance to European invasion.
weakened American Indian tribes significantly,
making them more vulnerable to European invasion.
Oled large numbers of American Indians to seek
conversion to Christianity, believing that the disease
was a punishment from God.