290 DISEASES OF TRUE INFECTION 



anthrax must be rcnderetl harmless by burning the cadavers. Skinning 

 the animal is strictly forbidden. 



Rabies. 



{Hijdrophobia.) 



This is an acute disease of the entire nervous system caused by a 

 specific poison, and distinguished by a variable period of incubation, as 

 well as by an absence of any marked anatomical alteration. 



Etiology. — Rabies is a true infectious disease, and never occurs 

 spontaneously, but is only transmitted by direct infection through the 

 bite of affected animals. This disease, as a rule, is confined to the canine 

 race (dog, wolf, fox, hyena, and jackal). It is seen in rare instances in 

 the cat, horse, cattle, sheep, goat, deer, guinea-pig, rabbit, rat, mouse, 

 chicken, pigeon, and in man. The dog is the animal that contracts the 

 disease quicker than any other. Country, climate, care, nursing, age, 

 and sex do not seem to have any influence upon it. The disease is more 

 frequently seen in central Europe and in New England and Middle States 

 than anywhere else. This may be accounted for by the fact that dogs in 

 large numbers run at large, and also to the fact that the owners do not 

 conform to the rules of sanitary police. Rabies does not seem to be in- 

 fluenced to any great extent, by the seasons of the year, but cases are more 

 frequently seen in the spring and summer than in the autumn and winter. 

 The poison of rabies is as yet unknown, or at least it has not been definitely 

 described. It is reproduced in the body of the animal only; never outside 

 of it. It is mixed with blood, saliva in the salivary glands, and in the 

 secretions of the lachrymal glands. It is also said to occur in the mam- 

 mary glands. From direct inoculations, this disease appears in its most 

 concentrated form in the brain, spine, and in the ganglionic nerves. 



This poison is virulent in the spine and brain, during the incubative 

 period, and retains its full strength for several days after the death of the 

 affected animal. Roux and Nocard have found that the saliva is infectious 

 two or three days before any symptoms of the disease appear, and one 

 case recorded by Pampouki, in which a woman was infected by a dog 

 eight days before the actual symptoms appeared in the dog. The actual 

 excitant of the disease does not appear to be present in the muscles, the 

 lymphatic glands, liver or spleen, and the urine or spermatic fluid has not 

 been found virulent and the rabic poison has been found in very rare 

 instances in the aqvicous humor. The true cause of rabies has not as yet 

 been isolated and described, probably it is an ultra-microscopical organism, 

 at least it seems so to a large number of observers (Rimlinger, Riffet, 

 Rey, Schander, C'clli, Blase, etc.) , who have passed a brain emulsion through 



