14 THE IMPORTANCE OF DOMESTIC FLIES 



mosquitos in the transmission of yellow fever, also 

 reported on the typhoid epidemic in the camps in Cuba 

 during the Spanish- American War ; and he believed that 

 the outbreaks were certainly due to food contaminated 

 by flies. Vaughan, another member of the United 

 States Army Typhoid Commission, concluded in his 

 Report : (a) Flies swarmed over infected tecal matter in 

 the pits, and then visited and fed on the food prepared 

 for the soldiers in the mess-tents. When lime had been 

 recently sprinkled over the contents of the pits, flies 

 with their feet whitened with the lime were seen walking 

 over the food, (b) Officers, whose mess-tents were 

 protected by means of screens, suffered proportionately 

 less from typhoid fever than did those whose tents 

 were not so protected, (c) Typhoid fever gradually 

 disappeared in the fall of 1898 with the approach of 

 cold w r eather and the consequent disabling of the fly. 



Howard continues to quote Dr. Vaughan's Report : 

 " Tt is possible for the fly to carry the typhoid bacillus 

 in two ways. In the first place, fsecal matter contain- 

 ing the typhoid germ may adhere to the fly and be 

 mechanically transported. In the second place, it is 

 possible that the typhoid bacillus may be carried in 

 the digestive organs of the fly and be deposited with 

 its excrement." This last suggestion of Dr. Vaughan's 

 is most interesting, for the India Plague Commission 

 has shown that the bubonic plague may be conveyed 

 in this manner by rat-fleas from rat to rat and from 

 rats to human beings. 



During the Boer War the relation of flies to typhoid 

 was noticed several times. Nuttall and Jepson and 

 Graham Smith have collected much evidence from 

 various writers. Tooth and Calverley, writing of 

 typhoid in camps during the South African War, 



