Man's Mortal Enemies 19 



when the malaria-infeaed troops returned from the latter 

 war, our native mosquitoes took advantage of the opportunity 

 to spread malaria among the civilian population. And it is 

 highly probable that malaria victims among the veterans of 

 World War II have been the unwitting sources of recent 

 localized malaria epidemics in the United States. 



The name malaria is derived from two words: mal, 

 meaning bad, and air. Thus the literal meaning of the word 

 is bad air. Long before the role of the mosquito in the 

 transmission of the disease had been discovered, men knew 

 that in some way the air in the vicinity of swamps and other 

 wet places was dangerous. They believed, of course, that 

 evil spirits emanated from the swamps and entered their 

 bodies, causing the chills and fevers, and weakness. This 

 theory was almost correct. But unfortunately, no one real- 

 ized that the evil spirits had wings and a death-dealing bite. 

 Yet the idea of a relationship between swamps and malaria 

 was quite correct, for water \s essential for the breeding of 

 mosquitoes — during the larval stage they are aquatic insects. 



Since mosquitoes require water, we would except to find 

 malaria along the shores of the oceans, in river valleys, 

 around lakes and swamps, and in damp jungles — that is, un- 

 less the winters are too cold to permit mosquitoes to survive. 

 Inhabitants of Asia — particularly of China and India — Mex- 

 ico, Central America, South America, and the southeastern 

 part of the United States have all had to learn to live with 

 malaria. The use of screens on windows, the draining of 

 swamps, the application of oil and insecticides to breeding 

 places of mosquitoes have helped in some localities, but all 

 of these efforts have been insignificant compared to the bene- 

 fits conferred by a medicinal agent — quinine — extracted 

 from the bark of the cinchona tree. 



