Émile Roux

1853 (Confolens, France) – 1933 (Paris)

Roux was Duclaux’s protégé and assistant, Duclaux suggesting that Pasteur take him on. He became a close collaborator with Pasteur, working with him on avian cholera, anthrax and rabies (they developed a vaccine). Chamberland and he worked together; when Pasteur was awarded the Légion d’Honneur, he insisted Roux and Chamberland be honoured too. He helped Mechnikov with his work on syphilis (they succeeded in passing the infection to apes), and became his very close friend. Roux was joined by Yersin in his work on diphtheria, and succeeded Duclaux as director on the Pasteur Institute.

Robert Koch

1843 (Clausthal, Germany) – 1910 (Baden-Baden)

Koch did crucial research on anthrax, tuberculosis, cholera and other diseases, and with his associates was responsible for major advances in laboratory technique. He studied for his doctorate under Henle; they developed an important set of postulates. Cohn helped him by publishing his paper on anthrax; the influential Virchow was however antagonised by his work on tuberculosis. Koch and Pasteur conducted an acrimonious dispute about vaccination, further fuelled by current Franco-German rivalries. Always difficult to work with, Ehrlich, Behring and Kitasato were among his eminent students (he and Behring eventually fell out).

Robert Koch knew…