120 THE MILK QUESTION 



total of 842 cases was reported from Boston and the sur- 

 rounding towns of Chelsea, Winthrop, Cambridge, Somer- 

 ville, Milton, and Everett. Investigations showed that 

 most of the cases occurred on the route of one of the large 

 milk contractors. Of the 409 cases in Boston, 286, or nearly 

 70 per cent, were on the route of this dealer, while 123, or 

 SO per cent, used other milk. Of the 155 cases that occurred 

 in Cambridge, 126, or over .80 per cent, were on the route 

 of the same dealer. About the same proportion of the cases 

 in the other cities used the milk of this dealer. 



The epidemic cropped out suddenly April 25, and the 

 outbreak ceased May 7. The epidemic reached its highest 

 mark on April 29, on which day 123 new cases were re- 

 ported. The indications were plain that the outbreak was 

 the result of more than a single infection. The milk was 

 pasteurized on April 27, and three days following there was 

 a notable and sharp decline in the number of cases. The 

 actual source of the infection could not be traced, and it is 

 supposed that it consisted of a missed case on one of the 

 250 dairy farms from which the dealer obtained this par- 

 ticular supply of milk. 



Diphtheria 



The fact that diphtheria may be spread by milk was not 

 definitely recognized until very recently. The first epi- 

 demics apparently due to milk were reported in 1877 and 

 1878 in England. 



The bacillus of diphtheria will grow and proliferate in 

 milk at a prodigious rate. Like the typhoid organism it 

 does not appreciably change the appearance, taste, or color 

 of the milk. 



In almost all the epidemics that have been carefully 

 studied, the diphtheria bacilli gained entrance to the milk 

 from the secretions of the nose and throat of a person having 

 diphtheria or from a diphtheria bacillus carrier. Klein 

 and other English investigators believed that milk may be 



