76 



MILK AND THE PUBLIC HEALTH chap. 



the maid-servants, one of them being the nurse, were attacked, 

 botli of whom drank raw milk ; while the head of the house, 

 who only drank milk in tea, escaped, as did also the two 

 children (eight months and four years), receiving all their milk 

 boiled ; and this in spite of the fact that the nurse, whose sore- 

 throat was typical, but not severe, continued to look after 

 them." 



A more detailed illustration of the relationship between 

 the incidence of attack and the amount of milk consumed is 

 furnished by Sir William Power in the outbreak of milk- 

 borne scarlet fever at Wimbledon in 1887. He gives the 

 following table : ^ 



Diphtheria Outbreaks spread by Milk 



As long ago as 1878 Power adduced evidence that an 

 outbreak of diphtheria in Kilburn and St. John's Wood, 

 London, was spread by milk. Since that date many milk- 

 borne epidemics of this disease have been recorded, although 

 the total is smaller than of milk outbreaks of scarlet fever or 

 typhoid fever. 



Trask^ has summarised 51 such diphtheria outbreaks 

 (including those collected by Busey and Kober and by Hart) 

 spread by milk, while there are, no doubt, a very large 

 number which have never been recorded. 



The outbreaks summarised by Trask show a very variable 

 case-mortality, being for some as low as 1'5 per cent and for 

 others as high as 30 per cent, or even higher. The epidemics 

 with a high case-mortality are for the most part not recent, 

 and refer to pre-antitoxin times. The highest case-mortality 



1 Loc. cit. 

 - Balletiii Ku. 41, Puhlic Health ami Marine Hospital Sermse, 1908, p. 32. 



