240 THE CARRIAGE OF TYPHOID FEVER BY FLIES 



conversions are being made, and they show a falling-off of the 

 typhoid fever-rate coincident with this change. In Nottingham, 

 for example^ in the ten years 1887-1896, there was one case of 

 typhoid fever for every 120 houses that had pail-closets, one case 

 for every 37 houses with privy middens, and one case for every 

 558 houses with water-closets. The last were scattered, and not 

 confined to the prosperous districts of the town. 



Klein (1908) in discussing an outbreak of typhoid fever at 

 Wilshaw (Eng.) describes what is a common occurrence in very 

 many outbreaks in towns and cities. He says " After the occur- 

 rence of a case of enteric fever in a house forming one of a row, a 

 number of typhoid cases making their appearance in the neigh- 

 bouring houses. All known channels of transmission, for example, 

 personal contact, defective drainage, polluted water or milk, could 

 be excluded. The only condition common to all the houses of the 

 row was this — that they were swarming with flies." Klein made a 

 bacteriological examination of some of the " flies " (it is presumed 

 they were Musca domestica) after crushing them and found Bacillus 

 coll and B. typhosus. 



The insanitary conditions found in many of our towns and 

 cities are admirably suited in every detail for the breeding of flies, 

 the disease-carriers and for their carriage of the germs. In a 

 previous paper (1908) I have called attention to these facts. It 

 was pointed out that : " wherever there are collections of either 

 excremental products or decaying and waste vegetable substances 

 and food stuffs, house-flies are able to breed. Consequently, where 

 such conditions as the following exist we shall almost certainly 

 find house-flies : heaps of stable-manure and other excremental 

 products and house refuse which have stood for more than eight 

 or nine days, the time occupied by the development of the fly ; 

 such systems of excremental disposal as middens, dry ashpits and 

 pails which are not regularly removed within the same time. 

 I find that public tips frequently form permanent breeding places 

 for flies on account of the variety of substances tipped thereon. 

 House refuse and excremental substances should not be deposited 

 on public tips in the vicinity of houses but should be removed 



1 "Typhoid Fever and the Pail System at Nottingham," Lancit, Nov. 29th, 

 1902, p. 1489. 



