Mapping Early Epidemiology: Concepts of Causality in Reports of the Third Plague Pandemic, 1894–1950

The science of epidemiology has always had an intricate relationship to the history of diseases. The design of models of the dynamics that govern diseases in their relation to population is ultimately based on information and data gathered from past outbreaks. Epidemiology belongs to what Lorraine Daston has recently called “Sciences of the Archive.”1 Like astronomy, zoology, demography, or meteorology, the study of epidemics operates with objects of superhuman scale. The discipline deals with plagues that exceed historiographical periods and geographical regions; and, thus, it always requires elaborated practices of collecting, accounting, and archiving to establish its status as a discipline. Daston reminds us that despite this reliance of some “hard” sciences on the historical record, their conduct of history often differs from the perspective of humanists on the same historical event. Where exegesis, commentary, and interpretation of contexts and niches might characterize a history of diseases and epidemics, the epidemiological grasp on the historical record seeks to collect quantifiable data. But epidemiology wasn’t always a science of mathematical analysis, concerned with the production of formal expressions and the elaborate design of stochastic models. The epidemiology of the late nineteenth and early twentieth centuries is best described as a broad interdisciplinary project, suspended between isolated academics in medical schools and a growing group of governmental medical officers applying a mixture of methods, integrating