In an era when other physicians were "noncontagionists" and believed that infectious diseases were either "atmospheric" (airborne), arose from filth and neglect, or developed spontaneously in the soil, William Budd was a firm believer that infectious diseases, particularly cholera and typhoid, were contagious--that they were transmitted from one person to another through excrement. This theory was a forerunner to Louis Pasteur's germ theory.

Budd was born in the small town of North Tawton, Devon, to Samuel Budd, a surgeon, and Catherine Wreford, who came from an old Devon family. Budd was one of 10 children and the fifth of nine boys. All children received their early education at home; however, after Samuel inherited land from his grandfather, an Anglican minister, they were sent to prestigious universities. Six became doctors--three graduating from Edinburgh and three from Cambridge.

Budd's education was prolonged because of a severe attack of typhoid fever, which...