42 EPIDEMIC DISEASES TRANSMITTED BY MILK. 



of these diseases. That is to say, these diseases may occur as 

 a result of contaminated milk, and escape notice ordinarily. 



Typhoid fever. Typhoid is the most common of the epi- 

 demic type of infectious diseases. Little by little it is be- 

 ginning to be recognized that milk stands next to water as a 

 means for spreading infection. In this connection it is inter- 

 esting to note that typhoid fever is relatively more prevalent 

 in rural districts than in cities. Fulton has collected the fol- 

 lowing figures, quoted by Whipple (38) : 



TABLE II. 

 TYPHOID FEVER IN URBAN AND RURAL POPULATIONS. 



Investigations in the District of Columbia. During the past 

 two years very thorough investigations have been made of the 

 source of infection of the typhoid fever cases occurring in the 

 District of Columbia during the months May to October in- 

 clusive. The work was instituted in consequence of the obser- 

 vation that the installation of a satisfactory system of water 

 filtration did not produce a satisfactory lowering of the typhoid 

 fever rate. In 1906 it was possible to definitely assign a source 

 of infection in the case of only 18.6% of all reported cases 

 believed to have originated in the District'. Among these, 

 11.3% of all were attributed to milk and 7.3% to contact. 

 That is, 60.8% of all traceable cases were milk-borne. In 1907, 

 the figures were : traceable to milk, 9. 18% ; to contact, 19.50% ; 

 total accounted for, 28.68% . In that year 32 c /c of all traceable 

 cases were attributed to milk. 



