DISEASES PREVALENT IN THE ARMY 295 



extent in their cultural and serological reactions and in their 

 virulence for animals as do cultures isolated from frank cases 

 of disease. 



On the other hand, it is possible ofttimes to find differences in 

 the host, as in the case of typhoid carriers, cholelithiasis, or 

 some other disease process in the gall bladder is commonly 

 present. In the case of diphtheria carrier abnormalities in the 

 tonsils are common. We find, therefore, that the weight of 

 evidence is to the effect that a person becomes a chronic carrier 

 because of some more or less well-marked organic pathological 

 lesion in his tody, and in this abnormal tissue the invading 

 organism finds favorable conditions for a purely parasitic 

 existence. 



It was due to the presence among recruits arriving at our 

 camps of temporary and chronic carriers, as well as cases, that 

 one "after another of the acute infectious diseases developed 

 sooner or later among most of our troops. All of the diseases 

 of childhood, measles, mumps, scarlet fever, and also smallpox, 

 typhoid, dysentery and malaria were all introduced repeatedly, 

 yet only the first spread, as we had no method of rendering 

 soldiers immune to infection by vaccination as we did in the 

 case of smallpox and the typhoid fevers. Except for their 

 presence in such large numbers and their complications, there 

 was nothing of interest in these diseases. A few of the rarer 

 infectious diseases are of more interest and they will be briefly 

 discussed. Trench foot was distinctly a war disease, and was 

 due to the urniatuTaTenvl ronment in which troops were placed 

 because of the remarkable development of the system of trench 

 warfare. That it is preventable is now generally accepted, 

 and we suffered relatively little from it, because our men saw 

 comparatively little of trench warfare, and because of the 

 lessons learned from the experience of our Allies. It consists 

 of more or less damage to the skin, the underlying soft tissues 

 and blood vessels of the feet and legs from prolonged exposure 

 to wet and cold in tight or ill-fitting boots and shoes. The skin 

 is bruised, the soft parts and the blood vessels are constricted 



