A very remarkable sickness, the diffusion of directly transmitted, acute infectious diseases in the Petit Nord, 1670-1846

Abstract

This dissertation examines the epidemic history of the Petit Nord (eastern Manitoba and northwestern Ontario) in the period 1670 to 1846. It documents the incidence and diffusion of directly transmitted, acute infectious diseases ('ACIs') within the region. In addition to identifying the internal patterns of diffusion, it also delineates the circumstances that carried these diseases into the region. It is thus concerned with both the events surrounding particular epidemics and with the changing conditions that saw 'ACIs' introduced into the region from external sources. There are four main findings emanating from this research. First, it documents the early arrival of 'ACIs' in the Petit Nord, beginning in the seventeenth century. Among these were several epidemics that occurred prior to the 1779-83 smallpox epidemic, hich has been characterised in the historical literature as the first epidemic in the Canadian Northwest. Secondly, this study identifies an epidemic transition that occurred in the region during the 1830s and 1840s. With this transition the Petit Nord was visited increasingly by 'ACIs', including diseases that had never before entered the region. Similar transformations occurred elsewhere in the New World, and this research provides data on the nature of the changing circumstances that brought about these transitions. Thirdly, this dissertation delineates an important characteristic that was common to all of the epidemics that spread into the Petit Nord: their inability to diffuse to the limits of the region. No matter how virulent, each epidemic left some people untouched while others suffered the full brunt of its effects. Evidence presented here suggests that these differential outcomes had a significant impact on the people of the region, particularly with respect to changing territorial patterns. Finally, it documents a system of epidemic diffusion that regularly carried ' ACIs' from eastern disease pools westward across the continent. This system appears to have been far more significant as a threat to the Petit Nord than that which carried diseases from Mesoamerica through the Central Plains. Although these findings reflect the epidemic history of the Petit Nord, they also provide insight into the history of neighbouring regions, and of the New World in general.