TRANSMISSION OF DISEASES BY INSECTS 253 



t cases arose on shore when the only source of infection was a ship 

 at had not yet touched the land. These facts and many others 

 which formerly involved the disease in mystery, are now quite intelli- 

 gible in the light of the mosquito- theory of transmission. 



Finlay's Work. The pioneer work leading toward the control of 

 yellow fever was done by Dr. Charles J. Finlay, of Havana, Cuba, who 

 not only advocated the mosquito-theory strongly for many years, but 

 also inoculated by means of mosquitoes ninety human subjects, some 

 of whom came down with what he believed to be a mild form of yellow 

 fever. His valuable work prepared the way for the brilliant investi- 

 gations of Major Reed and his associates. 



United States Yellow Fever Commission. Major Walter Reed 

 was president of the board of medical officers sent to Cuba in June, 1900, 

 to study the acute infectious diseases of the island; his associates were 

 James Carroll, Jesse W. Lazear and A. Agramonte. 



At that time Sanarelli's theory as to the bacillary causation of yellow 

 fever was in favor, though Reed and Carroll has already shown that the 

 bacillus of Sanarelli bore no special relation to the disease. After further 

 investigations on this subject in Cuba, with negative results, the com- 

 mission " concluded to test the theory of Finlay," in Dr. Reed's words. 

 For this purpose General Leonard Wood, the military governor of Cuba, 

 gave permission for experiments on human beings and granted a liberal 

 sum of money for the reward of volunteer subjects. 



The commission succeeded in demonstrating how yellow fever is 

 transmitted ; after that the methods of prevention to be employed were 

 evident. 



The experiments, planned and directed by Major Reed, are models 

 of their kind. All possible sources of error were excluded; hence there 

 was no uncertainty in the interpretation of the results, the accuracy of 

 which has been confirmed by subsequent commissions and by many 

 independent investigators. 



In the value of his services Major Walter Reed ranks among the 

 greatest benefactors of mankind. Before his death, which occurred in 

 1902, he received great honors for his brilliant achievements. 



Experiments in Cuba. For experimental purposes Major Reed es- 

 tablished a camp about four miles from Havana. To prevent the 

 introduction of the fever from the outside the inmates of the camp were 

 rigidly quarantined; non-immunes were confined to the camp or, if re- 

 leased, not allowed to return. In order that the study of yellow fever 

 might not be complicated by the presence of any other disease, a com- 



