BANISHING THE PLAGUES 



1848, remained quite unheeded; as did Dr. Charles J. 

 Finlay's more detailed contention put forward in 

 1881. It was not until 1900 that the American au- 

 thorities in Cuba were prevailed upon by Dr. Finlay to 

 investigate his theory. Tests were made in which the 

 lives of several army surgeons were jeopardized and 

 that of one Dr. Lazear sacrificed. But in the end 

 the accuracy of the view that Dr. Finlay had so long 

 held was demonstrated. 



Then it became clear that malaria and yellow fever 

 are absolutely preventable diseases; that in order to 

 eliminate them it would only be necessary to check 

 the development of two tribes of mosquitoes for it 

 is a curious fact that only mosquitoes of the genus 

 Anopheles can serve as host for the malarial germ, 

 while only those of the genus Stegomyia can act in 

 similar capacity for the germ of yellow fever. 



The elimination of mosquitoes might seem, indeed, 

 to be no easy task; but that it is feasible in a region 

 under strict military surveillance to guard against 

 them most effectively, is clearly demonstrated in the 

 results achieved by Colonel Gorgas. 



BANISHING THE PEST-DISSEMINATING RAT 



While yellow fever and malaria are thus guarded 

 against through the waging of incessant war upon the 

 mosquito, the danger of the introduction of plague is 

 minimized by equally strenuous measures directed 

 against the common house rat, since this animal 

 serves as the host of the fleas that are the chief trans- 

 mitters of the dreaded "black death." 



It is now fully recognized that when the plague 



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