D'Hérelle , Felix

(1873–1949) French–Canadian bacteriologist

D'Hérelle, the son of a Canadian father and Dutch mother, was born in Montreal, Quebec, and went to school in Paris, later studying medicine at the University of Montreal. He worked as a bacteriologist in Guatemala and Mexico from 1901 until 1909, when he returned to Europe to take up a position at the Pasteur Institute in Paris. D'Hérelle moved to the University of Leiden in 1921 but after only a short stay resigned to become director of the Egyptian Bacteriological Service (1923). Finally, in 1926, d'Hérelle was appointed to the chair of bacteriology at Yale, a position he held until his retirement in 1933.

D'Hérelle is best known for his discovery of the bacteriophage – a type of virus that destroys bacteria. This work began in 1910 in Yucatan, when he was investigating diarrhea in locusts as a means of locust control. While developing cultures of the causative agent, a coccobacillus, d'Hérelle found that occasionally there would develop on a culture a clear spot, completely free of any bacteria. The cause of these clear spots became clear to him in 1915, while investigating a more orthodox form of dysentery in a cavalry squadron in Paris. He mixed a filtrate from the clear area with a culture of the dysentery bacilli and incubated the resulting broth overnight. The next morning the culture, which had been very turbid, was perfectly clear: all the bacteria had vanished. He concluded that this was the action of “a filterable virus, but a virus parasitic on bacteria.”

A similar discovery of what d'Hérelle termed a ‘bacteriolytic agent’ was announced independently by Frederick Twort in 1915. D'Hérelle published his own account first in 1917, followed by his monograph The Bacteriophage, Its Role in Immunity (1921). He spent the rest of his career attempting to develop bacteriophages as therapeutic agents. Thus, he tried to cure cholera in India in 1927 and bubonic plague in Egypt in 1926 by administering to the patients the appropriate phage. D'Hérelle himself claimed good results with his treatment, although in the hands of other workers the effect of phage on such diseases as cholera and plague appeared to be minimal. This conclusion d'Hérelle continued to resist until his death, claiming that no proper test using his methods had ever been carried out.

However, the importance of the bacteriophage as a research tool in molecular biology cannot be disputed. It was the so-called phage group, centered on Max Delbrück, that made many of the early advances in this discipline in the 1940s.