SECTION VI. 

 PREVENTIVE MEDICINE. 



PREVENTION of the spread of infectious diseases is one of the 

 most important and, at the same time, most difficult duties of the 

 veterinary surgeon, whether he be a private practitioner or engaged 

 in a municipal or state capacity. It is calculated at times to tax 

 the ingenuity and patience of the most resourceful and patient 

 worker. 



Each case must of necessity be treated according to its own 

 requirements, and these will be referred to under the heading of 

 each specific disease. There are, however, certain methods of 

 preventing the spread of infection that are common to all diseases, 

 and a consideration of these forms the basis of all preventive 

 medicine. 



Naturally there are difficulties to be overcome, and they are due 

 to many causes, among which may be mentioned the great resistance 

 of some infective agents; the insidious nature of many infectious 

 diseases in which the animal may be an active carrier and dissem- 

 inator without giving any indication of the fact until the disease 

 has become more or less widespread; the constant and wide 

 traffic of animals which favours the spread of infectious maladies, 

 and at the same time increases the difficulty of tracing and 

 controlling the carriers of the infection ; the indifference and care- 

 lessness with which some stock-owners, fortunately in the minority, 

 regard contagious diseases, and, with what sometimes amounts to 

 criminal negligence, fail to notify the presence of scheduled disease 

 among their stock, or to take such precautions as are incumbent upon 

 them for the safeguarding of their neighbours. Failure to recognise 

 a disease or to suspect its existence has on more than one occasion 

 been the cause of widespread trouble. An outstanding instance of 

 this was the outbreak of foot-and-mouth disease in Ireland, where 

 an unqualified " animal doctor " failed to appreciate the fact that he 

 was confronted with this most infectious of diseases. The diseases 

 normally non-existent in this country, such as foot-and-mouth disease 

 and rabies, may not be detected, especially in their early stages. 



The very nature of infective micro-organisms favours their 

 spread. Being minute and light they are conveyed hither and 

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