SELECTED PAPERS 



visible with the aid of the electron microscope. Thus it has revealed 

 itself as a minute spherical particle with a diameter of o.oooi mm. 

 Many of you may remember the epidemic of 1918 which also in our 

 country carried off a large number of persons in the prime of life. But 

 it is possible that you may not realize that this tragic event was but a 

 small part of a world-wide pandemic that attacked 500 million people, 

 and killed 15 million. During the height of the disease the death toll 

 amounted to one for every fifty individuals per month, a death rate 

 never before encountered. In the U.S.A. 500,000 persons succumbed 

 in the course of 4 months, a number considerably in excess of the 

 total American losses during the second world war. 



In connexion with these figures the American scientist, Stanley, 

 remarks : 



'I have never been able to understand mankind's resigned and 

 complacent acceptance of such a major catastrophe as the 1918 out- 

 break of influenza. True, the cause of influenza was unknown in 191 8, 

 but one would think that such a calamity would result in a great 

 public demand for a concerted effort to discover the cause of the dis- 

 ease and to develop methods of protection. But this great destruction 

 of human life was accepted almost as ancient peoples accepted natural 

 catastrophes as acts of the gods, and hence beyond the control of 

 man.' 



Stanley then goes on to describe how not until more than twenty 

 years later, as a result of the war effort, the American 'Committee on 

 Medical Research of the Office of Scientific Research and Develop- 

 ment' was supplied with the means to carry out large-scale investiga- 

 tions. We owe to these studies not only our visual acquaintance with 

 this minuscule scourge of mankind, but also its mass-cultivation in 

 chick embryos, and the transformation of the virus so obtained into a 

 protective vaccine. Even though the situation is greatly complicated 

 by the existence of a number of different types of influenza, Stanley 

 nevertheless does not hesitate to claim that man now possesses the 

 means to prevent forever a recurrence of influenza as one of the major 

 destroyers of human life. 



Even to-day dangers continue to threaten. As proof for this state- 

 ment I mention the cholera epidemic in Egypt where the first cases 

 were reported on September 23 of last year. In the beginning the 

 situation looked grave; the epidemic rapidly spread over all of Egypt. 



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