848 THE EIGHT AGAINST YELLOW FEVER. 



is no contagion from the infected persons, nor from their clothing, 

 nor even from their faeces, bnt only by infected mosquitoes, which, in 

 the case mentioned, were confined on a vessel. What a i)aradox it 

 seemed to epidemiologists of that time that of two cities — Barcelona 

 and Marseille — one clean and new, the other insanitary and old, it was 

 the fii'st Avliich was visited by the yellow fever, while the second 

 remained nntouched. There is no longer a paradox for those who 

 know that one cit}^ is on the northern and the other on the southern 

 side of the frontier that limits the habitat of the contaminating 

 ni(js(iuito. 



The forty-third parallel strikes the continent of Europe at Ferrol, 

 in Spain, follows the Pyrennes districts, crosses the Ilyeres Islands 

 below Marseille to the heights of Leghorn in Italy; it leaves below 

 it nearly all of Spain, the southern half of Italy, and of the French 

 possessions part of the Hyeres Islands and of Corsica. Care should 

 be taken in directing to any one of these islands any French colonial 

 companies returning from yellow-fever countries. 



The infectible countries, possible prey for the pestilence, comprise, 

 as may be seen, a considerable enough portion of P^urope, the whole 

 of Africa, a large part of Asia, of Australia, and the oceanic islands. 

 Here is an innnense empire that must be watched. It will become 

 more and more formidable, as direct relations are nndtiplied with 

 the different endemic centers of Brazil, the Antilles, and the (iulf of 

 (luinea. The cutting of the Isthnnis of Panama, by opening to the 

 jdague Polynesia and the Asiatic world, might create a menacing- 

 danger. 



The way to prevent this extension is to attack the agent of its 

 propagation, the Stegomyia, both on land and sea; on land by trying 

 to purge the endemic centers wdiere the insect becomes infectious, 

 and on sea by attempting to destroy the mosquito itself in the ships 

 Avhere it finds refuge. 



Three signal victories have been gained over yellow fever during 

 these later years — in Cuba, in P)razil, and in Dakar, in A^'^est Africa. 

 The first is the most memorable of these events. It is the purification 

 of the endemic center at Habana. This occurred in IDOl, during the 

 United States occupation. The daily press in countless articles has 

 spread the details. We know that Brig. Gen. Leonard Wood, gov- 

 ernor of Habana, decreed one fine day that the plague should be 

 wiped out and the mosquitoes destroyed throughout the entire city of 

 Habana and its suburbs, and we knoAV that it was done. Praise has 

 rightly been given to the spirit of decision, of activity, of energy, 

 and even Draconian rigor which attended the execution of this w^ork. 

 It remains to point out its wdsdom, its exact conformity to scientific 

 theories. 



