Félix d'Hérelle's major contribution to science was the discovery of the bacteriophage, a microscopic agent that appears in conjunction with and destroys disease-producing bacteria in a living organism. Like many researchers, d'Hérelle spent much of his life exploring the effects of his major discovery. He was also well-traveled; in the course of his life he lived for long or short periods of time in Canada, France, the Netherlands, Guatemala, Mexico, Indochina, Egypt, India, the United States, and the former Soviet Union.

D'Hérelle was born in Montreal, Quebec, Canada. His father, Félix d'Hérelle--a member of a well-established French Canadian family, died when the young Félix was six years old. After his father's death, he moved with his mother, Augustine Meert d'Hérelle, a Dutch woman, to Paris, France. In Paris, d'Hérelle received...