INTRODUCTORY 9 



with resulting neurasthenia. Scratching with 

 unclean fingers may cause the bites to suppurate, 

 and the multiplication of the sores may adversely 

 affect the general health. Lousiness is often the 

 cause of eczema in children with the consequent 

 serious glandular trouble. Lice have also been 

 shown to carry on their bodies the germs of 

 ophthalmia and no doubt contribute to the 

 spread of this disease. These malign effects, 

 though serious enough in themselves, do not 

 constitute by any means the real danger of lice. 

 In recent years it has been shown that three 

 serious epidemic diseases, typhus fever, relapsing 

 fever, and trench fever, are conveyed by them. 

 They have no direct connection with dirt or 

 famine, as was formerly supposed to be the case 

 with the first two. Without lice these diseases 

 would cease to exist throughout the greater part 

 of the world. Our own armies have fortunately 

 been spared the ravages of typhus and relapsing 

 fever during the present war, but have had a con- 

 siderable amount of trench fever, while prisoners 

 in the frightful prison camps of Germany have 

 in many cases been infected with the two former 

 diseases. We are therefore faced with the certain 

 introduction into this country of numerous 

 sufferers from one louse-borne disease and the 

 possibility of the introduction of two others. 

 In the absence of lice they would spread no 

 further. It therefore behoves us, for our own 

 safety and that of future generations, to wage a 



