Maxime Schwartz is a molecular biologist and a former director general of the Pasteur Institute. He is the author of Comment les vaches sont devenues folles and Des microbes et des hommes, qui va l’emporter?, both of which were published by Editions Odile Jacob.
Annick Perrot is a former curator of the Pasteur Museum.

In his native France, Louis Pasteur is a household name, revered as the scientist who developed the rabies vaccine, established the role of microbes in fermentation, refuted the theory of spontaneous generation, saved France’s silk production, and developed a vaccine for anthrax which was decimating cattle herds.
But what about Robert Koch, the German inventor of modern bacteriology and Pasteur’s contemporary? In France, his name generally evokes only the Bacillus that bears his name.
Yet, in his own country, Koch is regarded as a hero for discovering the bacteria responsible for tuberculosis and cholera. And in Germany, Pasteur is simply remembered for his work on vaccines.
This reciprocal ignorance reflects the fierce rivalry between the two scientists, at a time when political tensions between France and Germany were at their peak, following the Franco-Prussian War. Pasteur, a Germanophile in his youth, developed a deep hatred of Germany. And Koch, who had started out as a modest country doctor and risen to the height of scientific glory, was annoyed by the Frenchman’s rivalry and resented being cast in his shadow.
And yet both schools, the French and the German, developed an astonishing complementarity, thanks to which most infectious diseases have been overcome, at least in the developed countries.

• The impact of History and its conflicts on science and the history of science.
• The struggle between two great scientists, during the nineteenth-century rise of nationalism.