488 THE CONTROL OF MALARIA AND YELLOW FEVER 



seemed to indicate that the germ was transmitted by a carrier, 

 possibly an insect, and it took that length of time to grow in the 



Am. Museum of Nat. Hist. 



The numerous swamps of Havana were the breeding places for mosquitoes, and yellow 

 fever was very prevalent. By 1900, the effect of the extermination of mosquitoes began to be 

 evident in a lower death rate of yellow fever. 



insect's body. Probably the knowledge of the cause of malaria 

 gave these investigators clues on which they based these theories. 



People had formerly thought that j^ellow fever was transmitted 

 by fomites, substances such as garments and bedding, which had 

 been in contact with yellow fever patients and had absorbed the 

 germs. To test the fomes theory, an experimental hut was 

 filled with articles from a hospital for yellow fever at Havana. 

 Volunteers agreed to sleep in this hut. They did not contract 

 the disease. The experiment was repeated with a number of 

 persons and always with the same results, which definitely proved 

 that fomites did not transmit the disease. 



The theory that the disease was transmitted by mosquitoes 



