no MILK AND THE PUBLIC HEALTH chap. 



One of these streptococci was derived from a case of Ludwig's 

 .angina, and the other from a case of acute epiphysitis. 



The results are distinctive. Comparing the human and 

 the bovine groups, it was found that, although morphologic- 

 ally and culturally they were often indistinguishable, they 

 showed a wide divergence when their action towards animals 

 was considered. The bovine mastitis type was non-virulent 

 towards mice and other rodents, but possessed in marked 

 degree the power to cause udder inflammation in goats. The 

 streptococci from human sources possessed a considerable 

 virulence towards mice, but as regards the strains isolated 

 from sore throats absolutely, and as regards those from other 

 sources in most cases, they were unable to originate mastitis 

 in goats. 



These results suggest that an essential difference of 

 functional power separates the types, and that under ordinary 

 conditions the Streptococcus mastitidis is not a cause of human 

 disease. 



That the Streptococcus mastitidis is not a cause of human 

 disease was also demonstrated by dii-ect experiment. In two 

 separate experiments the writer directly infected his own 

 throat with massive doses of this streptococcus, isolated only a 

 ■day or two previously from cases of cow mastitis. On both 

 occasions no ill-effects were experienced generally or locally, 

 and the streptococcus could only be recovered with extreme 

 difficulty from his throat, and this although the isolation was 

 undertaken only two and three days respectively after the 

 throat inoculation, and although that inoculation was massive 

 in amount. 



On pathological grounds it would seem that the great 

 majority of cases of bovine mastitis are due to an organism 

 which is not harmful to man. This is in accord with the 

 fact that while bovine mastitis is common, sore throat and 

 ■other septic outbreaks from milk are rare. 



Epidemics of illness ascribed to this cause have nearly 

 always been of the nature of outbreaks of septic sore throat, 

 although there are one or two in which gastro-enteritis has 

 been the predominant condition. Hoist,-' for example, records 

 four outbreaks of acute gastro-enteritis from the use of raw 



^ Baumgarten's Jahresbericht, 189.5, p. 52. 



