AN INVESTIGATION ON EPIDEMIC 

 INFLUENZA 



BY PETER K. OLITSKY, M.D. AND 

 FREDERICK L. GATES, M.D. 



The Rockefeller Institute for Medical Research 



EPIDEMICS of influenza have occurred at Intervals 

 for centuries, and may be recognised from con^ 

 temporary descriptions though they were known 

 under different names in different places and different 

 times. The disease has had a wide or more restricted 

 distribution according to various circumstances of the 

 time, especially the rapidity and extent of the move- 

 ments of men. Thus in earlier centuries human trans- 

 port carried the pestilence slowly and over limited 

 areas; in modern times, in a world knit closely together 

 with frequent and rapid means of migration, the disease 

 passes quickly from country to country and from con- 

 tinent to continent. During the World War it quickly 

 exacted a death toll from the warring countries surpass- 

 ing their losses under arms. 



The place or places of origin of the epidemics are still 

 under investigation, and it remains for future study to 

 determine whether the spread takes place from a single 

 source or from many. History traces the outbreaks 

 of many epidemics to regions of eastern Russia and 

 Turkestan; but indications are not wanting that in- 



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