Bovine tubercle bacilli and disease in animals and man

Abstract

In 1882 Robert Koch reported the isolation oftuberkelbazillenfrom human and bovine sources. Sixteen years later, Theobald Smith (1898) demonstrated that strains of Koch's tubercle bacilli from these two hosts differed in cell morphology, cultural characteristics and virulence in rabbits. He did not believe that these variants were limited to the hosts from which they were isolated nor that the differences resulted from adaptations to a given host. Indeed, he remarked that ‘It might be better to omit the host designation of such varieties in order to anticipate assumptions that they are necessarily limited to the host whose name they bear.’ Nevertheless, heedless of his own misgivings he termed them the ‘human’ and ‘bovine’ types.