248 PASSIVE IMMUNIZATION 



DYSENTERY. 



While the attempts at prophylactic vaccination against infection 

 with the Shiga-Kruse bacillus have not led to very satisfactory 

 results (see p. 200), there is evidence to show that the use of the 

 corresponding antiserum exerts a beneficial influence upon the course 

 of the malady, when this has once developed. Regarding the mode 

 of action of the antisera which were first prepared by Shiga and 

 Kruse, there has been some controversy, it having been thought at 

 first that their effect was essentially bacteriolytic in nature. Subse- 

 quently, however, when it was shown by Kraust and Doerr that the 

 dysentery bacillus produces a true toxin, and that the same effects 

 could be obtained with an antiserum, produced with this as antigen, 

 the conclusion naturally suggested itself that the beneficial effects 

 reached with the older preparations, where unfiltered cultures includ- 

 ing the bodies of the bacilli represented the antigen, were probably 

 also owing to contained antitoxins. 



Preparations. The preparation of antidysentery serum is con- 

 ducted along similar lines as that of the other sera, which are used 

 for passive immunization, horses being employed as the antibody 

 producers. As in the immunization against diphtheria and tetanus 

 toxin a basic (Grund) immunity is first estabished by injecting a 

 certain quantity of antiserum together with, or twenty-four hours 

 preceding, the introduction of the toxin, or the toxin cultures, after 

 which the process is continued with these alone. 



Dosage and Uses. The serum which is used for curative purposes 

 in Vienna is of such strength that 0.1 c.c at most will protect a 

 rabbit weighing 1000 grams against a separate though simultaneous 

 intravenous injection of a single lethal dose of the toxin. The cura- 

 tive dose of such a serum for the human being varies between 10 

 and 20 c.c., which may be repeated several times in severe cases. 

 In extreme cases the French observers have used as much as 80 to 

 100 c.c. on the first day, and have repeated this on the following 

 days. In three instances 240, 380, and 1080 c.c. were injected 

 altogether, i. e., doses which seem unwarrantably and unnecessarily 

 large, if an active serum was really at hand. After the disease 

 comes under control, as is evidenced by a diminution in the number 

 of the stools, smaller doses may be given during the following days. 



For prophylactic purposes the same dosage (10 to 20 c.c.) is recom- 



