We hear often of how Europeans exposed Cholera, Tuberculosis, Smallpox, and other diseases to the native peoples of America and their devastating impact due to the lack of immunity. What diseases, if any, did the native peoples of America expose the Europeans to and what were their impact?

by rtkierke

My wife and I were reminded of this while watching The West yesterday evening and immediately wondered if there was a mutual exchange of harmful contagions.

hillsonghoods

Not to discourage further answers, but /u/anthropology_nerd's answer in the thread "One of the main reasons Europeans were so utterly victorious against Native Americans was the introduction of diseases, that decimated the population. Why did the Norsemen of Vinland not bring diseases that carried the same effect? answered a similar question fantastically well.