BIOLOGICAL THERAPEUTICS 



531 



animals, biologies stand out pre-eminently and considering them as a unit 

 it may be said that prophylaxis is their most valuable asset. As cura- 

 tive agents some biological products are very efficacious, but there are 

 others which while highly valuable in immunization against certain dis- 

 eases are of little or no value in the treatment of such affections. In 

 this respect I might mention Pasteur's rabies vaccine, blackleg vaccine 

 and anthrax vaccine. 



Biological Products Should Not Be the Sole Reliance in the Control 



of Disease. 



There is a tendency in the prevention and treatment of infectious 

 diseases to rely solely on the biological "products employed. It is highly 

 essential in attempting to treat or prevent a disease, to give due consid- 

 eration to the various factors associated with the condition. Thus in 

 treating a case of fistulous with- 

 ers we should not merely inject 

 a polyvalent vaccine and sit 

 down and wait for the animal 

 to get well, but the local or 

 surgical treatment should also 

 be given due consideration in 

 addition to the vaccine. Furth- 

 er, in attempting to control a 

 disease by immunization it is 

 not sufficient to limit our activ- 

 ities to vaccination of the ex- 

 posed and susceptible. animals, 

 but it is equally essential to in- 

 augurate the neeessar}' sanitary 

 measures, and, if possible, the 

 source of infection should be 

 looked for and eliminated. 

 Thorough disinfection, and ef- 

 forts to minimize the danger 

 of exposure to infection, also 

 should be considered. 



It must be remembered 

 that in serum or passive im- 

 munization, the immunity con- 

 ferred is only of short duration, lasting in most instances for only a short 

 period, at times not over a month. Therefore in cases of immediate dan- 

 ger when this method of immunization is employed, it is very important 

 to guard against the risk of subsequent infections and losses when the tem- 

 porary immunity has been lost. In such instances the passive immuniza- 

 tion should be followed up if necessary with the active form, which renders 

 the animal non-susceptible for a much greater length of time. 



Importance of the Technic of Administration. 



Another factor i^pP^JS^ia^tefggqff^ch must be given careful 

 attention, if good results are to ot obfamea, is the technic ot adrainistra- 



sterilizing- the Serum by Filtration Through 

 Berkefeld Filters 



