Unseen enemies: an examination of infectious diseases and their influence upon the Canadian Army in two major campaigns during the First and Second World Wars.




Dubord, Denis Gerard

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Twice during the first half of the twentieth century, on two separate and distinctly unique wartime campaigns in Europe, the survival of Canadian overseas armies was badly threatened not by enemy guns, but by the menace and ravages of an unseen enemy: infectious disease. Between the spring of 1915 and the fall of 1918, hundreds of thousands of Canadian soldiers lived and fought in the trenches of the Western Front. The Canadian Expeditionary Force (CEF) faced many tactical challenges in fighting this radical and unknown style of war in the trenches. There were also many medical challenges faced by the Canadian forces during this new era when they soon discovered that the trench environment was highly conducive to the rapid development and spread of infectious disease. In particular, pathogen carrying pests, such as body lice and rats, and “mysterious” emerging diseases, such as trench fever, would become the bane of existence for many Canadian soldiers. Life in the trenches would prove to be inherently dangerous for reasons other than enemy fire. Just two and one half decades later, during the Second World War, the Canadian First Division, recently victorious in occupying Sicily, was decimated, not by its German or Italian foes but by an epidemic of the mosquito transmitted infectious disease of malaria. Anti-malaria measures and precautions were well known, but the Canadians would discover that both the application of these practices and the compliance of the rank and file could not be taken for granted. This work examines the important influence disease vectors and infectious disease had upon the lives and experiences of our soldiers, as well as the conduct and outcomes of two important twentieth century military campaigns conducted by Canada’s army between 1914 and 1945. In essence, this study will explore and analyze Canadian attempts, both individual and corporate, to control, possibly defeat or at least come to terms with, its most elusive and silent enemies on the field of battle – infectious diseases.



Communicable diseases, Canada, World War, 1914-1918, World War, 1939-1945