The yearly outbreak of the common cold doesn’t really change much about society. But epidemics of plague, cholera and, most recently, Ebola, have affected not just health policy but military strategy and even the arts. Frank M. Snowden, the Andrew Downey Orrick Professor Emeritus of History and History of Medicine at Yale University, joins host Krys Boyd to talk about how infectious outbreaks — both terrifying and romanticized — have shaped our world, which he writes about in “Epidemics and Society: From the Black Death to the Present.”