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In pre-columbian exchange times, a variety of diseases existed in the Americas. The limited populations and interactions between those populations (as compared to places like Europe), hampered the development of widespread, deadly diseases in the Americas. One notable disease of American origin is syphillis. The American era of limited disease would end with the arrival of Europeans in the Americas. European diseases and epidemics, while still present among Native American populations today, were especially influential in Native American life of the past. Diseases and epidemics can be chronicled from centuries ago when European settlers brought forth diseases that devastated entire tribes. Transitioning into more modern times, similar diseases still plague Native American populations. The current crises in diseases and epidemics are being addressed by many different groups, both governmental and independent, and are done through a multitude of programs. 
 
Because Native American populations were not previously exposed to most diseases introduced by European colonists, populations rarely had built up individual or population immunities to those diseases. In addition, Europe's position as a crossroads between many different peoples, many of whom were separated by hundreds, if not thousands, of miles (through things like constant war spreading localized afflictions throughout the continent, and the silk road bringing diseases from the East), resulted in Europeans being immune to a large variety of diseases. Therefore, the diseases, which were brought by the Europeans and had little effect on them, greatly affected, and often continue to affect, Native Americans. This phenomenon is known as the virgin soil effect.

European contact