DISEASES COMMUNICABLE IN MILK 73 



distributed 400 qt. of milk to 175 customers. All the other dairymen 

 together distributed 1,200 qt. of milk. The infected dairy had 205 

 out of 232 cases; therefore, though it delivered but 25 per cent, of the 

 milk, it had at least 90 per cent, of the cases. Most of the milk of the 

 infected dairy came from a herd of 22 cows at Oceanside but in part 

 the milk came from two smaller dairies, R and C. All three of them were 

 investigated. 



At Oceanside it was found that the daughter of the owner, Miss W., 

 developed sore throat on April 16. Her mother came down with it on 

 May 9; she claimed to have been absent from the dairy until May 28. 

 A driver took the disease on May 11 and a milker on June 9. The greater 

 part of the milking was done by the owner and a milker but the driver 

 sometimes helped. On April 21, May 17 and May 21 isolated cases of 

 sore throat appeared among the customers. On May 30 two cases ap- 

 peared in a family that had its own cow; these cases and those at the 

 farm seem to have been of sporadic and contact origin. 



The material that was examined bacteriologically consisted of moist 

 swabs from the throat of every individual on the three farms supplying 

 the infected dairy and from a number of cases, as well as from a culture 

 from a complicating case of peritonitis. Milk from each quarter of all 

 the cows was put on ice over night and smears from the sediment were 

 examined. 



Five of the cows showed moderate numbers of streptococci in one or 

 more quarters and one of the animals gave physical evidence of mastitis. 

 Another cow showed moderate numbers of streptococci in two quarters 

 and enormous numbers of streptococci from one-quarter. Milk from this 

 quarter, owing to coagulation of the casein and separation of the whey, 

 was flocculent. 



All positive samples of milk were inoculated on blood agar plates. 

 The cultures from cows 2, 3, 4, 5 and 6 showed: on blood agar plates, no 

 hemolyses; on washed blood cells, no hemolysis; no fermentation of inulin, 

 raffinose, and mannit; fermentation of salicin. The milk from three- 

 quarters of cow 21 showed: hemolysis of blood agar plates; hemolysis of 

 washed blood cells; no fermentation of inulin, raffinose, and mannit; 

 fermentation of salicin. 



Twelve cases of septic sore throat were studied and hemolytic strep- 

 tococci in varying percentages were found present. Pure cultures were 

 isolated from each case and usually not only several hemolyzing but 

 also several non-hemolyzing types were found. At the Oceanside 

 dairy hemolyzing types were obtained from the driver, milker and a wash- 

 woman who had enlarged tonsils but denied illness; no hemolyzing types 

 were obtained from Mrs. W. At Farms R and C there had been no cases 

 of illness and no hemolyzing types were found except from Mrs. R. who 

 had enlarged tonsils. The non-hemolyzing types were studied only in 



