380 MILK AND DISEASE 



primary case developed among his customers his dairy would be 

 closed. Rumors of the affair spread through the town and his 

 customers left him and the family moved away, after which there 

 was no more typhoid fever. 



3. It frequently happens that the better class suffer more than 

 do the poor, as they can afford more milk and use it more freely. 



4. There is a special incidence among milk drinkers, there fre- 

 quently being an individual who dislikes milk escaping, whereas 

 the remainder of the family is attacked. 



5. Women and children are more often victims in milk-borne 

 typhoid than are the adult male population due to their use of raw 

 milk. 



6. There is some evidence \vhich indicates that the incubation 

 period is shorter and the mortality lower in milk-borne epidemics 

 than in others. 



The mild character of the disease is usually attributed to the 

 attentuation of the pathogenic properties of the microorganisms 

 through their growth in milk. 



7. Milk epidemics of typhoid spread over a rather short milk 

 route, whereas wiien milk is brought from a considerable distance 

 there is not the likelihood of infection, thus indicating that typhoid 

 germs tend to disappear from milk under certain conditions. 



Extent of Milk-borne Disease. The extent of milk-borne epidemics 

 cannot be accurately measured, as even at the present day many 

 cases go undetermined or perhaps attributed to other causes. But 

 the experience of Boston, Massachusetts, which has a fair milk 

 supply indicates the gravity of the subject. 



Year. Epidemics. Cases. 



1907 Diphtheria 72 



1907 Scarlet fever . 717 



1908 Typhoid fever 400 



1910 Scarlet fever ... 842 



1911 Septic sore throat 2064 



Total 4095 



This indicates that scarlet fever and septic sore throat may be 

 conveyed even more often than typhoid fever. 



Tuberculosis is the most important of all milk-borne diseases, 

 both because of the frequency with which it is conveyed and the 

 seriousness of the disease. It may be either bovine or human in 

 origin. Human infection is rarer than bovine, but it is certain that a 

 tubercular patient may infect milk, and Hess in 1918 actually isolated 

 the human tuberculosis bacillus from a sample of market milk. 



Koch in 1901 announced that there was practically no danger of 

 man's contracting tuberculosis from cattle, but his statement was 

 immediately challenged by many bacteriologists who have since 

 brought forth conclusive evidence of the falseness of Koch's dictum. 



