The arrival of Europeans also brought on the Columbian Exchange. During this period European settlers brought many different technologies and lifestyles with them; arguably the most harmful effect of this exchange was the arrival and spread of disease.
Numerous diseases were brought to North America, including bubonic plague, chickenpox, cholera, the common cold, diphtheria, influenza, malaria, measles, scarlet fever, sexually transmitted diseases, typhoid, typhus, tuberculosis, and pertussis (whooping cough). Each of these brought destruction through sweeping epidemics, involving disability, illness, and extensive deaths. Native Americans, due to the lack of prior contact with Europeans, had not previously been exposed to the diseases that were prevalent on the distant continent. Therefore, they had not built up internal immunities to the diseases or formed any medicines to combat them. Europeans came into the New World bearing various diseases. Those infected with diseases either possessed them in a dormant state or were not quarantined in such a way that distanced them enough from Native Americans not to spread the diseases, allowing them to spread into epidemics.
The trade of Native American captives, and the use of commercial trade routes continued the spread of disease. The diseases brought by Europeans are not easily tracked, since there were numerous outbreaks and all were not equally recorded. The first documented epidemic was 1616–1619. The most destructive disease brought by Europeans was smallpox. The Lakota Indians called the disease the running face sickness. Smallpox was lethal to many Native Americans, bringing sweeping epidemics and affecting the same tribes repeatedly.
Between 1837 and 1870, at least four different epidemics struck the Plains tribes. When the plains Indians began to learn of the "white man’s diseases", they intentionally avoided contact with them and their trade goods. But many tribes were enamored with things like metal pots, skillets and knives, and they traded with the white newcomers anyway, inadvertently spreading diseases to their villages.
Certain cultural and biological traits made Native Americans more susceptible to these diseases. Emphasis placed on visiting the sick led to the spread of disease through consistent contact. Native Americans first exposed to these diseases also had a unique approach to illness, relating primarily to religious beliefs. There is the belief that disease is caused by either a lack of charm use, an intrusion of an object by means of sorcery, or the free soul's absence from the body. Disease was understood to enter the body if one is not protected by the spirits, as it is a natural occurrence. Religious powers were believed to be related to curing diseases as well. Native American illness has been treated through the practice of shamanism in the past, though this decreased as the influence of Europeans increased.