468 Rabies. 



this Mas intracranial, tlie disease usually coiniuenees with mania and 

 a desire to bite. 



The virulence of street virus varies within a rather wide range, 

 and this is also indicated by the varying periods of incubation 

 after subdural inoculation in rabbits. According to d'Amato, the virus 

 from cats, foxes and wolves has a more violent effect than that from 

 dogs. 



The natural infection is brought about in tlie majority of 

 cases by man or animal being bitten by a raljid animal, whereby 

 the virulent saliva is inoculated through the wound into the 

 subcutaneous tissues, muscles or nerves ; in rare cases the con- 

 tagion has been introduced by licking of wounds and skin abra- 

 sions. The saliva is most virulent immediately after the onset 

 of the disease and in its further course but it is also infectious 

 in a lesser degree 2 to 5 clays before the appearance of the 

 symptoms (Ro'ux & Nocard, Nicholas), and in cases described 

 by Pampouki and Konradi even 8 days before the appearance 

 of the first s;^anptoms. On the other hand during the long period 

 of incubation preceding these days, the saliva is not infectious 

 but it may be virulent for 5 days after the animal has reco^^erefl 

 (Remlinger). Finally, there exists a possibility of transmitting 

 the disease by means of milk from diseased animals (Perroncito 

 & Carita, Nocard). 



The danger from a bite depends on the one hand on the 

 virulence of the saliva, on the other hand upon the size, that 

 is the depth of the wound, and further on the number of nerves 

 and lymphatic vessels in the wounded part of the body. Large 

 w^ounds offer large surfaces for absorption, and from small but 

 deep wounds, the virus once entered, can hardly be removed, 

 wdiile from small, superficial wounds it is easily removed by 

 means of bleeding. Therefore, the serious wounds inflicted by 

 animals of prey, especially wolves and large rabid dogs, and 

 the deep wounds inflicted by the sharp, pointed teeth of cats 

 have an equally l)ad reputation, while the bites of the herbiv- 

 orous animals are less dangerous. 



Rabies is particularly frequent after infectious bites in parts 

 of the body where nerves and lymph vessels are plentiful and 

 which are near to the brain or spinal cord. Wounds on the lips, 

 cheeks, and nose are considered as especially dangerous, and in 

 horses and cattle the infection comes mostly from these parts of 

 the body. The density and thickness of the layer of hair or wool 

 covering the point bitten is important as it might withhold the 

 saliva. Similarly human beings are often protected against in- 

 fection on account of the thickness and density of their clothing. 

 Thick wool especially renders such protection, and this is in ac- 

 cord with the experience, that bites of rabid animals are much 

 more' dangerous for clipped sheep than for those that have a 

 dense covering of wool. 



The contagion, be it ever so virulent and concentrated, 

 cannot penetrate through the uninjured skin, while the possi- 



