Hellmuth Unger, the writer of the book about Robert Koch, which the movie is based on, was a member of the "Race political bureau of the Nazi party", the former "Education bureau for population policy and race care". He wrote many journalistic articles about the race hygiene propaganda and worked on the subject of children euthanasia.
During the filming of the movie a university professor was there to make sure that the scientific tools are used properly. All sets and tools were recreated based on the photos of the original places.
Unlike portrayed in the movie Rudolf Virchow honored Robert Koch's work and didn't hate it. He was critical towards him especially regarding the tuberculosis bacillus and the anthrax pathogen but he wasn't an antagonist as in the movie. The rumor that Virchow was against Koch was created through this movie. This was made because of Virchow's research and dissertation that explains that Germany doesn't have any "pure race" but are all mixed. This analysis was made by Virchow in 1857 and again in 186 which showed different hair-, skin- and eye colors in about 7 million kids, including Jewish kids too. This was against the ideology of the National socialists, which is why he was defamed by the Nazis.