322 MILK AND DISEASE 



the public makes the question of the transmissibility of 

 the disease to mankind through the consumption of this 

 article of diet a matter of first-rate importance. 



A great amount of research has been made into the 

 relationship between bovine and human tuberculosis, the 

 mode of infection of animals and man, and the morpho- 

 logical and physiological variations of the bacilli derived 

 from various sources ; many of the points raised in the 

 investigation of these problems are still unsettled. 



Koch, the discoverer of the bacillus, put forward, in 

 1901, the view that the organisms responsible for human 

 and bovine forms of the disease are distinct, at any rate 

 in infective power, and maintained that the bacilli of 

 tuberculosis in cattle are very rarely, if ever, responsible 

 for the disease in man. 



Of course definite experimental proof by inoculation 

 is out of the question, but the Royal Commission ap- 

 pointed to investigate the problem, although its final 

 conclusions are not yet forthcoming, has obtained suffi- 

 cient reliable evidence to confute Koch's statement. 



It has been found that the bacilli derived from bovine 

 tuberculosis infect calves, pigs, cats, dogs, the Rhesus 

 monkey, and the chimpanzee, when inoculated into the 

 system or supplied to the animals in food ; they are 

 therefore not specially adapted to attack cattle only. 

 The experiments have also shown that the bacilli derived 

 from human sources are able to produce the disease when 

 given in the food or introduced by inoculation into calves, 

 rabbits, monkeys, and apes. 



The Commission has already reported that : " There 

 can be no doubt that in a certain number of cases the 

 tuberculosis occurring in the human subject, especially in 

 children, is the direct result of the introduction of the 



