Jason Opal (McGill University) joins the Infectious Historians. Jason begins by discussing the massive impact of disease on the Americas between the 15th and 18th centuries, while also acknowledging the realization of this history in the 1970s. He also touches upon the concept of “virgin soil” epidemics. The second part of the episode focuses on inoculation against smallpox in Europe, the colonies and elsewhere. Jason discusses how inoculation was done and the different ways in which it was adopted. He also touches upon the relevance of measles to this story. The last part of the interview discusses teaching epidemics, as Jason shares with Merle and Lee how he teaches disease.