INFECTIOUS DISEASES. 559 



fractory double outline. Furthermore, the injection of mallein in 

 cases of sporotrichosis will be attended with negative results. 



Treatmeivt. — ^At the onset of the disease treatment consists in entire 

 extirpation of the nodules, in case the lesions are localized. In 

 cases in wMch the nodules have formed abscesses, their opening is 

 recommended, followed by the application of the actual cautery or a 

 1 to 250 solution of bichlorid of mercury. It must be borne in mind 

 that the organism is quite resistant to antiseptics, and the best results 

 will be obtained from the application of a solution of a strong anti- 

 septic following the opening of the lesions. Internally, potassium 

 iodid is recommended in 2-dram doses, dissolved in drinking water, 

 twice a day. 



In the most favorable cases recovery results in from five to seven 

 weeks; as a rule, however, it requires several months. 



In order to prevent the spreading of the disease the affected ani- 

 mals should be isolated, the products of the disease should be de- 

 stroyed, and the stable should be disinfected with very strong liquid 

 disinfectants in consideration of the resistance of the causative or- 

 ganism. 



RABIES, HYDROPHOBIA, OR MADNESS. 



Rabies is a contagious disease, which is usually transmitted by a 

 bite and by the introduction of a virus contained in the saliva of an 

 affected animal. It may, however, be transmitted in other ways. It 

 is characterized by symptoms of aberration of the nervous system 

 and invariably terminates fatally. It is accompanied with lesions, 

 inflammation, and degeneration in the central nervous system. It is 

 a disease that is most common in the dog, but is transmitted to the 

 horse, either from dogs or from any other animal affected with it. 

 (See also remarks on page 244.) As a disease of the horse it is 

 invariably the result of the bite of a rabid animal, usually a dog. 



Perhaps no disease in medicine has been the object of more con- 

 troversy than rabies. Certain medical men of prominence have 

 even doubted its existence, and many others have claimed for it a 

 spontaneous origin. The experience of ages, however, has shown 

 that contagion can be proved in the great majority of cases, and, 

 by analogy with other contagious diseases, we may only believe that 

 the development of one case requires the preexistence of a case from 

 which the virus has been transmitted. Pasteur has further added 

 to our knowledge of the disease by showing that a virus capable of 

 cultivation exists in the nervous system, especially in the lower 

 part of the brain (medulla oblongata) and in the anterior part of 

 the spinal column. He has further shown that that portion of the 

 nervous system which contains the virus, the exact nature of which 

 has not yet been demonstrated, will retain it for a very long time 



