Émile Roux was a French physician, bacteriologist, and immunologist who became a prominent figure during the golden age of microbiology. His work at the Pasteur Institute placed him at the forefront of the battle against infectious diseases. Roux is recognized as one of the founders of immunology and was a close collaborator of Louis Pasteur.
Early Life and Collaboration with Pasteur
Pierre Paul Émile Roux began his medical studies in 1872 at the Medical School of Clermont-Ferrand. He later continued his education in Paris, where he met chemist Émile Duclaux. Duclaux recommended Roux to Louis Pasteur, who was seeking assistants for his laboratory at the École Normale Supérieure. In 1878, Roux joined Pasteur’s team, marking the beginning of a long collaboration.
As one of Pasteur’s most trusted associates, Roux was involved in developing a vaccine against anthrax, a disease affecting livestock and humans. He and his colleague, Charles Chamberland, were instrumental in the public experiment at Pouilly-le-Fort, which demonstrated the vaccine’s effectiveness.
Roux’s technical skills also proved valuable in rabies research, contributing to the methods that led to the first human rabies vaccine. This period working alongside Pasteur solidified his reputation as a meticulous researcher.
Pioneering Diphtheria Treatment
In the 19th century, diphtheria was a widespread and feared disease, particularly for its effect on children. It was often called “the strangling angel” because it could cause a thick grey membrane to form in the throat, leading to suffocation. The mechanism of the disease was not understood until the work of Roux and his colleague, Alexandre Yersin, at the Pasteur Institute in 1888.
They discovered the systemic symptoms of diphtheria were not caused by the Corynebacterium diphtheriae bacterium spreading throughout the body. Instead, the bacterium remained localized in the throat and produced a toxin that circulated in the blood and caused the illness. This was the first bacterial toxin identified and it changed the understanding of how such diseases function.
This insight led to the development of serotherapy. Roux and his team began to inoculate horses with the diphtheria toxin. The animals’ immune systems responded by producing antitoxins, which could neutralize the toxin, and this antibody-rich serum was then collected from the horses.
In 1894, Roux, along with Louis Martin and Auguste Chaillou, began a clinical trial in Paris, administering the anti-diphtheria serum to children with the disease. The results were significant, with the treatment cutting the mortality rate by half. When Roux presented these findings at the International Congress of Hygiene in Budapest that year, he was celebrated as the “savior of children.”
Leadership and Lasting Legacy
After his work on diphtheria, Roux became the assistant director of the Pasteur Institute after Pasteur’s death in 1895 and then Director in 1904, a position he held for three decades until his death in 1933. Under his guidance, the institute solidified its reputation as a leading center for biomedical research and public health.
As director, Roux oversaw the expansion of the institute’s mission, including the founding of the Pasteur Hospital in 1900. This hospital was notable for providing free medical care and maintaining high standards of hygiene. He also established the first formal course on microbiology techniques, which trained scientists from France and around the world.
Beyond his administrative duties, Roux continued his own research, investigating other infectious diseases like tetanus, tuberculosis, and syphilis. He refused to personally profit from the commercial production of his anti-diphtheria serum, embodying a dedication to public service. His legacy is that of a scientist who saved countless lives and a leader who shaped a major institution that championed the use of science for the betterment of humanity.