DISEASES CAUSED BY INFECTED MILK 93 



probable that the damage caused by tubercle bacilli in 

 milk outstrip the consequences caused by any other spe- 

 cific infection thus conveyed. 



Tuberculosis is the most frequent and widespread of all 

 infectious diseases, whether of man or cattle. The economic 

 loss from tuberculosis in cattle is a matter of serious con- 

 cern to the dairyman. In this country nine per cent of all 

 human deaths and in Germany twelve per cent are caused 

 by tuberculosis. Most people die of tuberculosis during 

 the prime of life. In other words, thirty per cent of all 

 deaths between the ages of fifteen and sixty are due to 

 tuberculosis. Almost all of us have had the infection in 

 some form or another. Careful autopsies are able to dis- 

 cover the consequences of the invasion of the tubercle 

 bacillus into the tissues in almost every adult, no matter 

 what the cause of death. 



In this country it is estimated that 160,000 persons die 

 each year of tuberculosis. Stated in another way it may be 

 said that at least 5,600,000 people now living in this coun- 

 try are doomed to die of tuberculosis unless the disease is 

 checked. The loss of life and treasure is appalling. The 

 modern messages that tuberculosis is preventable and 

 curable have been received with a great sigh of relief. The 

 final control of this disease will be a crowning achievement 

 in preventive medicine. 



The difference between human and bovine tuberculosis. 

 The human and bovine tubercle bacilli resemble each 

 other closely. The essential differences lie in the fact that 

 the human type is very pathogenic for man, but has little 

 power of producing disease in cattle, rabbits, guinea-pigs, 

 monkeys, and other animals. On the other hand, the bo- 

 vine type is very virulent for almost all mammalian animals 

 except man. 



The difference between the effects of the bovine bacillus 

 and the human bacillus in man may be better understood 

 from the fact that the bovine infection is apt to remain 



