Side view of house fly from enlarged model made by Mr. Ignaz Matausch. The house 

 fly has not the long biting proboscis characteristic of the stable fly which transmits infantile 

 paralysis. Compare with figure on page 230 



by the victims of the disease. In the next year Mr. C. T. Brues, an en- 

 tomologist, was assigned to work with Dr. Sheppard and suspicion began to 

 point strongly toward a particular insect, the biting stable fly. Finally in the 

 summer of 1912 Prof. M. J. Rosenau of the Harvard Medical School com- 

 pleted the chain of proof. No one who was present at the joint session of 

 Sections I and V of the Fifteenth International Congress of Hygiene and 

 Demography on September 26th last will forget that most striking event 

 of the whole Congress, the presentation of these results. Eminent investi- 

 gators from Norway, Sweden and Austria, as well as some of the leading 

 workers in this country, had presented the formal papers of the morning. 

 Much that was important was added but the weight of evidence still seemed 

 to point, though somewhat doubtfully, toward human contact as the chief 

 agent in the transmission of the disease. In the discussion that followed, Dr. 

 Rosenau made a preliminary report of his experiments and announced that 

 he had succeeded in producing poliomyelitis in six out of twelve monkeys 

 bitten by stable flies (Stomoxys calcitrans) which had been allowed to feed 

 on other monkeys suffering from the disease. As a result of his discovery 

 the entire outlook for the control of infant paralysis has been changed. 



Prof. Rosenau 's work has since been confirmed by Drs. Anderson 

 and Frost of the United States Public Health Service. There is of course 

 no certainty that the disease is always transmitted by Stomoxys. The 

 work of Dr. Flexner and of the Swedish observers and the occurrence of a 

 certain proportion of cases in cold weather strongly suggest that sometimes 



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