VACCINATION. IMMUNIZATION. INOCULATION 235 



5 weeks after the injection (tuberculosis of the peritoneum and the 

 abdominal organs). This method can also be used in the diag- 

 nosis of glanders (guinea-pigs). 



7. The intra-ocular inoculation consists in introducing the 

 infectious material by means of a fine injection needle through the 

 cocainized cornea into the anterior chamber of the eye. It is 

 used for the purpose of diagnosing rabies (rabbits, dogs) and also 

 to obtain pure cultures of the tubercle bacillus (rabbits). 



8. Galactiferous moculation is the term used to designate 

 injections through the teat canal into the udder by means of 

 canula-like needles or milk tubes (mastitis bacteria). 



9. " Feeding inoculation " is the feeding of infectious material 

 to experimental animals (tuberculosis, anthrax, chicken cholera, 

 swine plague, hog cholera). Intra-intestinal infection is the injec- 

 tion of the material into the intestines. 



2. THE DIFFERENT VARIETIES OF VACCINATION 

 Purposes of Vaccination. — ^While formerly, vaccination was 

 almost exclusively applied to healthy individuals for the purpose 

 of producing immunity to a possible subsequent infection (pro- 

 tective vaccination), it has been more recently employed for other 

 purposes. First of all, mention must be made of the curative vacci- 

 nation, which has latterly occupied a place in the foregroimd of 

 therapeutic interest. Its object is to render assistance to the indi- 

 vidual in which infection has already taken place (post-infection 

 vaccination), while protective vaccination is employed before infec- 

 tion (pre-infection vaccination). In addition, vaccination is fre- 

 quently resorted to to establish a diagnosis. This diagnostic vac- 

 cination has for its object neither protection nor healing but the 

 production of the disease in question as rapidly and in as definite 

 form as possible, or the generation of fever (tuberculin, mallein) for 

 the purpose of establishing the presence of disease. Accordingly, 

 the following varieties of vaccination may be recognized: 



(a) Protective vaccination (pre-infection inoculation). 



(b) Curative vaccination (post-infection inoculation). 



(c) Diagnostic vaccination. 



