BACTERIOLOGY OF MILK 453 



children. In some instances it has been found possible by 

 marking the location of infected families on a map to show 

 the milk route of some individual. Inasmuch as typhoid 

 fever is not a disease of cattle it is apparent that the organ- 

 isms can gain access to milk only after milk has been drawn, 

 through careless handling, use of contaminated water, or 

 perhaps more commonly by contact with a typhoid carrier 

 or one who is just coming down with the disease or has 

 recently recovered from it. Scarlet fever and diphtheria 

 have apparently in some cases been transmitted through 

 milk. Inasmuch as these no more than typhoid are diseases 

 of animals, it is apparent that the organisms have gained 

 access only through careless handling. 



The more important of the organisms which may be pres- 

 ent in market milk is the Bacillus tuberculosis which has 

 already been discussed, as has also the relationship of tuber- 

 culosis in animals to the disease in man. It seems to be a 

 well-demonstrated fact that the use of milk from tuber- 

 culous animals causes a considerable percentage of the cases 

 of tuberculosis, particularly of the scrofulous type, in chil- 

 dren. Milk used for human consumption should, if possible, 

 be secured from animals that have been proved to be free 

 from disease. If this is impossible then pasteurization 

 should be resorted to. 



Other diseases which have been occasionally transmitted 

 by the milk of the cow are foot and mouth disease, milk sick- 

 ness, Malta fever and anthrax. These diseases are very rare 

 and occur only occasionally in animals in the United States. 

 They are an unimportant type of disease in man. 



Numerous instances in recent years have been recorded in 

 the United States of cases of so-called septic sore throat, 

 caused by a species of the genus Streptococcus. It is prob- 

 able that in some cases the organism has entered the milk 

 from human carriers, but in other cases it is possible that it 



