Because they had never been exposed to European diseases, Indians 
had no immunity against them. Among the most devastating were 
smallpox, chicken pox, measles, influenza, malaria, tuberculosis, 
cholera, and whooping cough. Within four decades of Columbus's 
arrival, millions of Indians had died from epidemics. There was 
significant depopulation among Native American by early 17th 
century, continuing into the 19th century. Indian immunities 
gradually strengthen with the increased exposure and intermingling 
with whites, but the steady dwindling of the population severely 
strained the individual Indian cultures. Some white doctors tried to 
address themselves to the problem by publishing medical guides 
specifically  for Indians. Shown here is the title page of one 
published in 1818.