86 MILK AND THE PUBLIC HEALTH CHAP. 



typhoid bacilli and so mechanically infect the milk. In one 

 typhoid fever outbreak spread by milk, inquired into by the 

 writer, this source of infection seemed a likely one, as un- 

 doubtedly the cows supplying the specifically infected milk 

 had been in the habit of standing in a stream (and drinking 

 its water) polluted with the sewage effluent of a large town 

 containing at the time cases of typhoid fever. Further inquiry, 

 however, detected the presence of an unrecognised case of 

 enteric fever amongst those handling the rnilk, and this case 

 was probably the source of infection. 



The typhoid bacillus is said to have been isolated from 

 milk on a number of occasions, but in nearly all the proofs 

 advanced in favour of the identity of the isolated bacilli with 

 B. typJiosus would not now (in the light of present knowledge 

 as to pseudo-forms) be deemed sufficient to establish the 

 contention, and must be accepted with reservation. 



Shoemaker * has reported an interesting means of infection, 

 and claims to have isolated the typhoid bacillus in connection 

 with an outbreak of milk-spread typhoid fever in Philadelphia 

 in 1906. It was spread from a certain dairy, and in regard 

 to this he remarks : " The son was convalescing from typhoid 

 fever and was filling the milk bottles from a tank by siphonage, 

 starting the flow by sucking with the mouth at one end of the 

 tube. A culture made from this end of the tube revealed 

 many typhoid bacilli." He also stated that " a culture made 

 from the milk proved the presence of the typhoid bacillus in 

 it." The facts as to the means of spread are very interesting, 

 but since the report gives not the slightest evidence or informa- 

 tion as to the characters of the so-called typhoid bacilli, their 

 presence cannot be accepted as proved. 



SCARLET FEVER SPREAD BY MILK 



The number of recorded outbreaks of scarlet fever spread 

 by milk is large, while undoubtedly numerous outbreaks are 

 unrecorded. Trask has collected information in regard to 125 

 such epidemics, while the writer has notes of a large number 

 recorded in the literature not included in Trask's summary. 

 The sources through which the milk becomes infected with the 



1 Journ. Amer. Med. Assoc., May 1907, p. 1748. 



