Frederick Novy and the 1901 San Francisco plague commission investigation.

The 1900 San Francisco plague is a significant event in which citizens, physicians, and public health officials denied a diagnosis of plague on economic, political, and social grounds. To resolve the controversy, Surgeon General Walter Wyman appointed an independent federal commission of university-based experts to investigate whether plague was present. I use the activities of Frederick Novy, the commission bacteriologist and professor at the University of Michigan, to explore one circumstance in which bacteriology attempted to redefine traditional conceptions of disease during the early germ era. Novy showed plague was present in the city but without its characteristic clinical features and devastating epidemiological pattern. Physicians who understood plague by its classic features, however, contested Novy's scientific evidence. His bacteriologic redefinition had no special authority to prevail over opposing conceptions about plague; it was accepted and acted upon once it served the overall interest of the city--to avert a trade embargo.