252 ANTHRAX BACILLUS 



such animals as sheep, horses, and donkeys. These animals first 

 receive vaccine No. 1 and No. 2 in the usual doses and intervals. 

 About two weeks after the last vaccination they receive an injection 

 of a more virulent culture. This injection is repeated in from ten to 

 fourteen days, always with cultures of greater virulence, or with 

 increasing doses of a virulent culture. All injections are made 

 subcutaneously, not intravenously. After two or three months of 

 this treatment the serum of the hyperimmunized animals has obtained 

 a high value. If injected in doses of 20 to 25 c.c. into horses, cattle, 

 and sheep it produces a passive immunity which will protect the 

 treated animal against anthrax infection for several weeks, or perhaps 

 at best for two or three months. The serum has also proved effective 

 as a curative agent after anthrax infection has taken place, but it 

 must then be used in larger doses of 30 to 150 c.c. In cases of human 

 local infections (carbuncle) the antiserum has been used in doses 

 of 30 to 40 c.c. injected subcutaneously in three or four different 

 places on the body; in very bad cases another set of injections of the 

 same doses should be made after twenty-four hours. It has also 

 been used in bad cases in 10 c.c. doses as an intravenous injection. 

 Sobernheim has worked out and used on animals, with excellent 

 results, a combined, simultaneous method of active and passive 

 immunization. He uses vaccine No. 2 (J c.c. for horses and cattle, 

 J c.c. for sheep and goats), and injects it subcutaneously into one 

 side of the animal, while the other side receives 4 to 5 c.c. of the 

 antiserum. The advantages of this combined method are that it 

 requires only one treatment and that the animals are fully protected 

 after ten to twelve days. It appears that the simultaneous method 

 is absolutely safe and that it has never led to any fatalities following 

 its proper use. The last 50,000 vaccinations, according to Sobern- 

 heim, were made without a single death. 



It is well to state, however, that nothing is known at present con- 

 cerning the mechanism of the action of the antiserum. It does not 

 contain an antitoxin, because the anthrax bacillus does not form 

 soluble toxins. It does not increase phagocytosis and it does not act 

 as a bacteriolytic agency. It acts in some way as a bactericidal 

 antiserum. It seems to prevent the anthrax bacilli from leaving the 

 place of injection and entering into and multiplying in the general 

 circulation. It causes them to die out in the subcutaneous tissue 

 after a comparatively short time, though by no means immediately. 



