Total war is a term of the twentieth century that describes a war in which countries or nations mobilize and force to the limit all available resources, whether human, military, industrial, agricultural, natural, technological, scientific, or of any other kind, to totally destroy the ability of another country or nation to engage in a war. The practice of total warfare has been used for centuries, but it was not until the mid-nineteenth century that it was recognized as a different way of waging war.
A clear example of this represents the German effort during the First World War.
The author wanted to illustrate how scary yellow fever was, he left the city in Knox' hands and had even wrote to him a letter right before he left, on Sept 9 of 1793, telling him to leave if he thought it was necessary.