From 1877 to 1879 he was assigned to the Imperial Health Office (German: Kaiserliches Gesundheitsamt) in Berlin, where he became an assistant to Robert Koch.
Od 1877. do 1879. bio je dodijeljen carskom zavodu za zdravstvo (njemački: Kaiserliches Gesundheitsamt) u Berlinu, gdje je postao pomoćnik Robertu Kochu.