CHOLERA, PLAGUE, TYPHOID FEVER 125 



Something, here and there : more, in course of 

 time : but the difficulties are colossal. Possibly, 

 the final salvation of India from plague may come 

 not from man, but from Nature : it is not impos- 

 sible that future generations of rats should be born 

 immune against plague. The terror of plague is 

 just in this fact, that it is, strictly speaking, not a 

 disease of man, but a disease of rats.* 



Serum- Treatment of Plague. 



The first use of this treatment was by Yersin, 

 in 1896, in Canton and Amoy. That the serum, 

 when it is used for protection against plague, is 

 valuable, nobody doubts : but this protection lasts 

 only a very short time.f Used for the actual 

 treatment of plague-stricken patients, it gave good 

 results in China ; but the results in India were not 

 well marked. Against that worst type of the 

 disease, pneumonic plague, which is contagious 

 from man to man, neither serum nor any other 

 treatment is of much use. 



* " II ne faut pas oublier, en effet, que la peste n'est 

 qu'accidentellement line maladie humaine." Dujardm-Beau- 

 metz, Bibl. de Ther., xii., p. 462. 



t " Chez Thomme, Pefficacite du serum antipesteux em- 

 ploye preventivement n'est plus a demontrer, et tous ceux 

 qui Font utilise de cette fa^on sont d'accord sur ce point; 

 mais cette action presque immediate n'est que passagere et, 

 apres une dizaine de jours, toute immunite a disparu, et 

 Pindividu, n'etant plus sous Tinfluence serique, est a la merci 

 d'une atteinte pesteuse, s'il ne prend la precaution de recourir 

 une nouvelle injection de serum.'" Dujardin-Beaumetz. 



