no 



MILK BACTERIA AND HEALTH. 



settlement that the conclusions here given may require modi- 

 fication in the light of further experiment. The relation of 

 milk as a distributor of tuberculosis may be briefly sum- 

 marized as follows : 



1. Bovine tuberculosis and human tuberculosis are essen- 

 tially the same disease, although there is a certain amount 

 of difference between them. The identity of these two dis- 

 eases has long been suspected, but was not demonstrated until 

 the two diseases were shown to be caused by the same micro- 

 organisms. Although the disease in man and cattle shows 

 more or less differences there is practically no question 

 to-day that they are to be regarded as the same. 



2. Both forms of this disease are produced by the well- 

 known Bacillus tuberculosis, a bacillus which is identical, in 

 most respects, whether it be found in the human being or in 

 the cow (Fig. 21). There has, however, within the last two 



FIG. 21. 



Tuberculosis bacillus, a, in a bit of animal tissue; b, showing irregularities resembling 

 spores ; c, typical appearance of the bacilli from ordinary cultures. 



years appeared a vigorous discussion whether the bacilli 

 from the two sources are strictly identical. Professor Koch, 

 in a famous address in London in the summer of 1901 (122), 



