THE PRESENCE IN MILK OF CERTAIN ORGANISMS 261 



A very severe epidemic of streptococcal sore throats occurred 

 in Cambridge, Mass., in the winter of 1911-12, and was dealt with 

 by several authors (cp. Winslow and Darling). It was known that 

 730 cases occurred, but the real number was probably considerably 

 above this. Twenty-seven deaths occurred among the persons 

 attacked, of whom the majority were over forty years of age. 

 Children appeared to be comparatively immune. The bacterial 

 content of the milk supplied from the dairy was fairly low, being 

 approximately 300,000 per c.c. Two-thirds of the samples examined 

 gave a count below 50,000 and half of the samples below 10,000. 



Capps and Miller investigated an outbreak of sore throats 

 in Chicago due to streptococcal infection of the milk supply. The 

 epidemic presented features of considerable interest and involved 

 about 10,000 cases, which is considered to be a conservative esti- 

 mate. A number of deaths occurred as a result of the infection. 

 The outbreak was divided into two parts : the first occurred about 

 September 21, rising in intensity to the 25th,when it rapidly subsided. 

 The second outbreak of cases, which was not so numerous, occurred 

 on January I and 2, with a slight interruption from the loth to 

 the I7th of this month. The epidemic was worse in some parts 

 of the city than others, and was bad in the village of Batavia, 

 which lies just outside Chicago. The source of infection was traced 

 to a dairy whose pasteurising plant was in Batavia. It was found 

 that a few days before each of the outbreaks there had been serious 

 defects in the pasteurisation, which had been especially bad on 

 December 17 and December 19. The milk appears to have been 

 consumed two or three days after pasteurisation and the incubation 

 period to have been about four days. An interesting point arises 

 in the fact that at one children's hospital which was supplied 

 with milk from this dairy the children did not suffer at all, although 

 the nursing and medical staff suffered severely. Investigation 

 showed that the milk supply for the children was delivered raw 

 and pasteurised in the hospital before being given to the children, 

 while the milk supplied for the staff was obtained direct from the 

 dairy, where it was supposed to have been pasteurised and did 

 not undergo any further heating. Investigation on the farms 

 which supplied milk to the dairy showed that there had been 

 an unusual number of cases both of mastitis in the cows and of 

 sore throats in several of the persons on the farms supplying the 

 milk to the dairy. Samples of milk supplied from the farms were 

 found to contain pus and streptococci. 



Outbreaks due to milk infection were reported upon by Fletcher 

 in Woodbridge in 1913-14, and by Macewen in South London. 

 In the latter case the epidemic appears to have been due to infection 

 from the teats of the cows, which was also found on the milkers' 

 hands. At the time of the investigation the Klebs-Loeffler bacillus 

 was isolated from the hands of two of the milkers; The pustules 

 on the cows' teats had however become dry and the organisms 



