On etiology and therapy of tuberculosis in the Netherlands (1900-1910) During the first decennium of this century there was a discussion on the etiology of tuberculosis in the columns of the leading Dutch medical journal Nederlandsch Tijdschrift voor Geneeskunde. On the one hand there was a movement in favour of the heredity of tuberculosis, on the other hand the contagiousness of the tubercle bacillus was stressed by the supporters of the bacteriological dogma. Robert Koch's lecture on the difference between the human and the bovine tubercle bacillus held on the international tuberculosis congress in London in 1901 stirred the Dutch controversies. Koch doubted the contagiousness of bovine tuberculosis for men, while many Dutch physicians had experienced cases in which the opposite was shown. Moreover Dutch investigations could not show the differences between both types of tubercle bacilli and Koch's authority did get a blow. To obtain more information on the heredity of tuberculosis the Dutch Medical Association held an inquiry among its members on the prevalence of tuberculosis in married couples and their families. However, very few data were compiled so no conclusion was possible. After the death in 1906 of the professor in hygienics, A.P. Fokker (1840-1906), a fervent opponent of Koch's doctrines, the contagiousness of tuberculosis became more and more accepted. The social implications of a bacteriological approach caused some hesitation among medical doctors and in the implementation of a tuberculosis programme. Raising the economic level and improvement of the conditions of living was thought to be as important in the battle against tuberculosis. Different theories about the factors causing tuberculosis were based on the mortality figures. The influence of the soil, the race, the economic standard of living, housing, air, food or infection could all be demonstrated by using mortality figures. No rational therapy for tuberculosis was available. Rest in a special healthy climate in a sanatorium seemed to ...