92 DDT— Killer of Killers 



cipal carrier of a number of diseases, the most serious of which 

 is epidemic typhus. 



Fortunately, cleanliness is the enemy of the louse, and 

 since about the only people in this country who seem to have 

 an almost pathological dread of soap and water are those care- 

 free citizens known variously as hoboes, tramps, and bums, it 

 is only among this group of individuals that the body louse 

 is found to any great extent in the United States. Thus, 

 louse-borne diseases are of relatively little importance in this 

 country. But in other parts of the world, the situation is 

 quite the opposite. Millions of inhabitants of Europe, Asia, 

 and Africa live under conditions of filth almost unbelievable 

 to an inhabitant of a country where the greatest bulk of radio 

 advertising is devoted to the sale of soap. 



An adult body louse is a rather good-sized brute, about 

 % inch long, and grayish in color. It emerges from a whit- 

 ish egg, or nit, which hatches at body temperature about 8 

 days after the egg is laid, and spends about 9 days in the 

 nymphal stage, during which it sheds its skin three times as it 

 grows to an adult. And if our louse happens to be a female, 

 she begins to lay eggs about a day after she emerges as an 

 adult, and she may live as long as a month, laying 4 or 5 

 eggs each day. 



The body louse makes its home in its host's clothing, 

 and it leaves its home several times a day to visit its host's 

 skin and acquire nourishment. Sometimes the female lays 

 her eggs on the hairs of the body, but usually she deposits 

 them in her host's clothing, particularly in the seams and 

 folds. And she glues her eggs to the fibers of the cloth. 



Since the body louse does not live on the body but 

 rather in the clothing, it is relatively easy to control this un- 

 welcome boarder. All stages of the louse are killed by 



