76 



CITY MILK SUPPLY 



Summary of Epidemics. In Table 30 are set forth some of the lead- 

 ing facts concerning the principal epidemics in this country. The wide- 

 spread serious character of the outbreaks, taken into consideration with 

 the fact that in many of them the management of the dairies was more 

 than usually intelligent and conscientious, convinced the experts who in- 

 vestigated them that the health of milk consumers could be effectively 

 protected only by pasteurizing the milk under thorough inspection. 



TABLE 30. PRINCIPAL EPIDEMICS OF SEPTIC SORE THROAT IN THE UNITED STATES 



(a) Including Brookline and Cambridge. 



(fe) Figures for Cambridge alone; under 15 years, 15; 16 to 25 years, 20; and over 20 years, 64. 



(c) 306 patients whose sex is unknown. 



(d) 85 patients of unknown sex. 



(e) Besides these were 128 boys in St. Paul's School. 



(/) Besides these there were 25 girls in St. Mary's School. 



Mode of Transmission of Infectious Disease. Having named the 

 diseases that are transmitted by milk, the ways in which they infect it 

 must be considered. In the first place, it should be recognized that there 

 are two sources of danger, animals and men. Of these the former 

 are the least important for, with the exception of septic sore throat, 

 which primarily is of human origin, and of bovine tuberculosis, not many 

 of their diseases are communicable to man and those that are so are 

 relatively rare. The virus of a few of them such as tuberculosis, foot- 

 and-mouth disease and septic sore throat are in the milk as it comes from 

 the udder. Tubercle bacilli also are contained in the feces of dis- 

 eased cows which dropping into the milk infect it. Milk may also be 

 infected by droolings from the animals and by pustular and vesicular 



