1034 ■ SOCIÉTÉ DE BIOLOGIE 



INSECTS AND INFECTIONS 



AT THE FRONT 



by F. MESNIL and E. ROUBAUD 



As soon as trench warfare started, the question of insects came up not 

 only because they ^ve^e objectionable in themselves, but aiso because 

 they were able to transmit diseases. Considered from the latter view- 

 point, they can be divided into two classes : first, insects which do not 

 bite, such as the domestic fly, and which can only carry virus in a 

 passive way; second, insects which bite and draw the éléments of 

 infection from the blood and in which the microbes undergo an évolu- 

 tion : mosquiloes, phlebolomus, fleas, lice. 



Flies. — The epidemiologic action of Aies must certainly be very 

 important in army agglomérations. A distinction must be made 

 betweon hiting Flies, which are apt to cause a lésion of the tégu- 

 ments and suck the blood, and non bitlng Fixes which are unable to per- 

 forate the skin and take nourishment from varions liquid products. 

 The latter must also be divided into two groups according to their bio- 

 logy and according to their relation to man. 



1. BiTiNG Flies (gad Flies, Stomoxes and simiiar types and ail kinds 

 of small Flies, gnats or sand flies, Simulium, Ceralopogon, etc.) Thèse 

 Flies do not seem to altract particular attention, at least not on The 

 Frencli front. One must, however, consider the possibility of a 

 mechanical diffusion of infections éléments drawn from the blood. 



2. HousE Flies (domestic Fly, lesser house Fly : Fannia canicularis ; 

 latrine Fly : Fannia canicularis, elc.) — Thèse non biling Flies live in 

 permanent contact with man in houses. Therefore they must hâve a 

 very important part in the diffusion of germs taken either from man or 

 from suppurations or excréta which he éliminâtes (bronchial expecto- 

 ration, sputa, excréments.) 



a) Pathogenic action of the domestic Fly. — This Fly, which is not 



