152 HEALTH AND DISEASE 



demonstration, because it is impossible to prove that the infection has 

 originated in the organism, in face of the fact that the atmosphere is 

 capable of conveying the spores of bacteria into the animal's body. The 

 following diseases of the horse in the present day, among others, are in- 

 cluded in the term contagious, infectious, or epizootic affections: Anthrax, 

 variola (horse pox), tetanus, pyaemia, malignant oedema, contagious stoma- 

 titis, purpura, strangles, influenza, contagious pleuro-pneumonia (which 

 belongs to the influenza group), cerebro-spinal meningitis, tuberculosis, 

 and certain affections of the skin, as mange, ring-worm, and epizootic 

 lymphangitis, depending on the invasion of animal or vegetable parasites. 



PREVENTION AND SUPPRESSION OF INFECTIOUS DISEASES 



Prevention. Preventive measures are of the utmost importance in 

 relation to all diseases. They have a special value when directed against 

 infective disorders on account of the peculiarity which those maladies 

 possess of extending the area of their prevalence, unless severe restric- 

 tions are imposed upon the movement of diseased or infected animals, 

 and even of persons or substances which have been in contact with them. 



Prevention naturally occupies the first place in dealing with infective 

 diseases; its immediate object being to oppose, as far as possible, their 

 introduction into a country or a district. 



The measures of suppression can only be employed when the disease 

 has been introduced, and it becomes necessary to check its progress. 

 Preventive measures in relation to the infective diseases of the horse 

 must necessarily be limited in the majority of cases to individual 

 action, as all the maladies which have been named already exist in the 

 country, and every purchaser of a horse incurs a certain amount of risk 

 of introducing an infected animal into his stables. Glanders appears 

 to be the only affection which could be consistently dealt with by 

 any restrictive enactments against the entrance of animals from those 

 countries in which the disease is known to exist. The horse-owner may, 

 however, protect himself by the exercise of care in the selection of fresh 

 animals, and further, by enforcing a certain period of quarantine on his 

 own premises, for the purpose of satisfying himself that the animal is free 

 from the more common infective diseases, such as those which belong to 

 the catarrhal group influenza and strangles, for example. It is also 

 possible for him to ensure perfect cleanliness and thorough disinfection, 

 and he can avoid purchasing second - hand harness, clothing, brushes, 

 buckets, or any apparatus used about the stable; or at least, in the event 

 of such things being introduced, it is not difficult to have them properly 



