THE MANUFACTURE OF VACCINES. 477 



to fifteen days. Tests of both vaccines for activity and safety are made 

 by animal inoculations. Vaccine No. i should kill white mice but 

 should not cause fatal results in guinea-pigs or rabbits. Vaccine No. 2 

 should prove fatal for both white mice and guinea-pigs, but not for 

 rabbits. 



Healthy animals are first injected subcutaneously with about i c.c. 

 of vaccine No. i. Several days or a few weeks after the application of 

 vaccine No. i, the second vaccine is injected. A severe reaction and 

 sometimes death follows the use of the vaccine. Accidents of this 

 kind have resulted from careless methods employed in standardizing 

 and administering the vaccine. The most important objection to Pas- 

 teur's anthrax vaccine is due to the danger involved in the use of the 

 attenuated but living anthrax organisms. Promising results have 

 been obtained from the practical use of anthrax vaccine consisting of 

 the killed and dried anthrax organisms. 



Sclavo* advocates the use of the serum from animals actively im- 

 munized to anthrax. This method may be employed either in the form 

 of the immune serum alone, or the immune serum and anthrax culture, 

 simultaneously. 



OTHER VACCINES. 



The study of vaccines and serum therapy occupies a position of so 

 great importance in preventive medicine that many new vaccines are being 

 constantly added to the list of experimental products. Some of these 

 have been under observation for a considerable time and are recognized 

 as possessing valuable properties. Because of the importance and 

 prevalence of Asiatic cholera, bubonic plague, tuberculosis and typhoid 

 fever, brief references may properly be made to the attempted specific 

 preventive treatments relative to these infectious diseases. 



ASIATIC CHOLERA. Two methods of vaccination against this disease 

 have been proposed and statistics which relate to field tests show positive 

 results in both cases. The method of vaccination resulting from the work 

 of Haffkinef depends upon the use of cultures of the spirillum of Asiatic 

 cholera, attenuated by growth at temperatures above the optimum. 

 Vaccines of different strengths are used. KolleJ has proposed the use 

 of heated (killed) cultures of the organism. 



* Sclavo: Centralbl. f. Bakt, 1989, 26. 



f Haffkine: Brit. Med. Jour., 1895, 2. 



t Kolle: Deut. Med. Wochenschr., 1897, 23. 



