Rabies and Hydrophobia. 261 



Animals susceptible. While the disease is seen most frequently 

 in the canine races (dogs, wolves, foxes and jackals), and in the 

 cat family (cat, lion), it is liable to spread widely among animals 

 that use the teeth as weapons of offense, and such as they can 

 readily attack. When inoculated, all warm blooded animals con- 

 tract the disease. Thus the carnivora and omnivora (dog, wolf, 

 fox, hyena, jackal, cat, lion, badger and skunk and, to a less 

 extent, the pig and horse) may become active propagators of the 

 infection, which may spread widely among their herbivorous vic- 

 tims (cattle, sheep, goats, deer, rats, mice, chickens and pigeons) 

 through their bites. Man suffers mainly through the attacks of 

 dogs, cats and, in certain localities, wolves or skunks, but he is 

 also liable to become infected from handling rabid domestic 

 herbivora. Different genera differ in susceptibilit3^, the recep- 

 tivity being apparently greatest in the carnivora. 



Geographical Distribution. Rabies is confined to no country 

 nor climate but it attains its greatest prevalence in the north tem- 

 perate zone, where there is the densest population and where 

 activity of travel favors the propagation of infection. The facility 

 for inoculation is the one determining cause, thus the islands of 

 Australia, Tasmania, New Zealand, the Azores and St. Helena 

 have never suffered and the first three exclude the disease by 

 rigid inspection and quarantine. During the Hamburg epizootic 

 of 1852-53, the islands in the Elbe escaped though both banks 

 were ravaged. Again, where the muzzling of all dogs has been 

 rigidly enforced, as in many German cities and districts the dis- 

 ease has been practically extirpated. 



Etiology. Long before the days of pathological bacteriology 

 rabies was recognized by veterinarians as a disease due to infec- 

 tion alone. Its absence from the various countries above named, 

 and from South and West Africa, its rapid propagation in other 

 countries (Da Plata, Malta, Hong Kong) into which it had been 

 introduced for the first time, and its restriction and disappearance 

 wherever muzzling had been strictly carried out, had practically 

 settled this question. The development of the disease in animals 

 which had been experimentally inoculated was no less significant 

 of this truth. 



Other alleged causes are based on secondary factors that favor 

 inoculation. The alleged evil influence of the hot season (dog 



