"Historian David S. Barnes examines the birth of a new microbe-centered science of public health during the 1880s and 1890s, when the germ theory of disease burst into public consciousness. Tracing a series of developments in French science, medicine, politics, and culture, Barnes reveals how the science and practice of public health changed during the heyday of the bacteriological revolution." "This study sheds light on the scientific and social factors that continue to influence the public's lingering uncertainty over how disease can - and cannot - be spread."--Jacket.