Pierre Paul Émile Roux FRS (17 December 18533 November 1933) was a French physician, bacteriologist and immunologist. Roux was one of the closest collaborators of Louis Pasteur (1822–1895), a co-founder of the Pasteur Institute, and responsible for the institute's production of the anti-diphtheria serum, the first effective therapy for this disease. Additionally, he investigated cholera, chicken-cholera, rabies, and tuberculosis. Roux is regarded as a founder of the field of immunology. Early years Roux was born in Confolens, Charente. It is believed that Roux had a fatherless childhood. He received his baccalaureate in sciences in 1871 and started his studies in 1872 at the Medical School of Clermont-Ferrand. He worked initially as a student assistant in chemistry at the Faculty of Sciences, under Émile Duclaux. From 1874 to 1878, he continued his studies in Paris and was admitted as clinical assistant at Hôtel-Dieu. Between 1874 and 1877, Roux received a fellowship for the Military School at Val-de-Grâce, but quit it after failing to present his dissertation in due time. It is also believed that Roux may have been dismissed from the military for some form of insubordination. In 1878, he started to work as an assistant to the course on fermentation given by his patron Duclaux at the Sorbonne University. In 1878, Pierre Paul Emile Roux married Rose Anna Shedlock, but it was kept a secret. Shedlock met Roux at the Paris medical school. Shedlock then died in 1879 of tuberculosis. In an inaccurate biography, Roux's niece stated that Shedlock contracted tuberculosis from Roux. However, this is unlikely, given that Shedlock had symptoms before marrying Roux. According to his niece, Roux allegedly believed that marriage was an opportunity for women to satisfy their "deepest aspirations," while for men it was "mutilation". Work with Pasteur Duclaux recommended Roux to Louis Pasteur, who was looking for assistants, and Roux joined Pasteur's laboratory as a research assistant from 1878 to 1883 at the École Normale Supérieure in Paris. When Roux first began his career with Pasteur, he started as an animal inoculator. He performed well in the technical tasks, and became more involved with research. Roux began his research on the microbiological causation of diseases, and in this capacity worked with Pasteur on avian cholera (1879–1880) and anthrax (1879–1890), and was involved in the famous experiment on anthrax vaccination of animals at . In this vaccination experiment, Pasteur and Roux injected 25 sheep with