What Is an Epidemic? AIDS in Historical Perspective

Historic and Prehistoric Epidemics: An Overview of Sources Available for the Study of Ancient Pathogens

Since life on earth developed, parasitic microbes have thrived. Increases in host numbers, or the conquest of a new species, provide an opportunity for such a pathogen to enjoy, before host defense systems kick in, a similar upsurge in reproduction. Outbreaks, caused by "endemic" pathogens, and epidemics, caused by "novel" pathogens, have thus been creating chaos and destruction since prehistorical times. To study such (pre)historic epidemics, recent advances in the ancient DNA field, applied to both archeological and historical remains, have helped tremendously to elucidate the evolutionary trajectory of pathogens. These studies have offered new and unexpected insights into the evolution of, for instance, smallpox virus, hepatitis B virus, and the plague-causing bacterium Yersinia pestis. Furthermore, burial patterns and historical publications can help in tracking down ancient pathogens. Another source of information is our genome, where selective sweeps in immune-related genes relate to past pathogen attacks, while multiple viruses have left their genomes behind for us to study. This review will discuss the sources available to investigate (pre)historic diseases, as molecular knowledge of historic and prehistoric pathogens may help us understand the past and the present, and prepare us for future epidemics.

Closure and the Critical Epidemic Ending

"An epidemic has a dramaturgic form," wrote Charles Rosenberg in 1989, "Epidemics start at a moment in time, proceed on a stage limited in space and duration, following a plot line of increasing and revelatory tension, move to a crisis of individual and collective character, then drift towards closure." Rosenberg's dramaturgic description has become an important starting point for critical studies of epidemic endings (Vargha, 2016; Greene & Vargha, 2020; Charters & Heitman, 2021) that, rightly, criticize this structure for its neatness and its linearity. In this article, I want to nuance these criticisms by distinguishing between the term Rosenberg uses, "closure," and its implicature, "ending." I aim to show how many of the complications ensuing between the different forms of ending imagined may well be resolved by assessing whether they bring closure or not.