1875 studied medicine, University of Utrecht; 1883 M.D. University of Utrecht; miltary physician on Java and Sumatra; since 1885 studied bacteriology at the Universities of Amsterdam and Berlin (under Koch); 1886 member of a committee to study the Beri-Beri disease in Dutch-India; 1887 director of the laboratory of pathology in Weltevreden, Batavia and director of the Javanese School of Medicine; 1896 return to Utrecht; 1898-1928 professor of hygienics and forensic medicine, University of Utrecht; Nobel Prize 1929.