Immunization. 599 



from the disease by tke Bang method the disease spread just as rapidly among the 

 vaccinated as it had spread among the unvaceinated animals at the time when the 

 Bang method was introduced. 



A favorable report is made by Strelinger with reference to his experience of 

 five years on the Domain of Sarvar in Hungary. During this time the percentage 

 of reactors was reduced to 9,6%, however, not without the simultaneous enforcement 

 of general prophylactic and hygienic measures. 



Pearson & Gilliland as well as de Schweinitz & Schroeder immunized cattle 

 in the United States by the intravenous injection of human tubercle bacilli. Detailed 

 reports of the practical results obtained have, however, not yet been published. 



2. Single Vaccination with Human Tubercle Bacilli (Vaccination 

 with Tauruman ; method of Koch & Schuetz) . According to the experi- 

 ments of Koch, Schuetz, Neufeld & Miessner it is possible to immunize 

 cattle against highly virulent bovine bacilli by means of a single in- 

 jection of 1 to 3 eg. of human tubercle bacilli (one dose of Tauruman 

 contains 0.01 gm. of virulent human tubercle bacilli in emulsion). 

 The resistance of animals thus immunized has been tested after a 

 period of at least 169 days in only three cases. If we consider that 

 a more durable immunity can hardly be expected from a single intra- 

 venous injection of human tubercle bacilli than from a double injection 

 of even larger doses of the same bacilli and further, that Tauruman 

 bacilli may remain active in the body of the treated animal for a 

 period of 2i/^ years the results of experimental investigations above 

 referred to as to the practical value of bovovaccine would probably 

 apply with equal force to the practical value of Tauruman. 



Although Tauruman has been used for -vaccination since 1905 extensive 

 reports on the practical results of its use are not obtainable. Eber reports on 

 the vaccination of 48 cattle on four different estates; after about two years 10 

 out of 21 of the vaccinated animals reacted to the tuberculin test. Weber & 

 Titze vaccinated 63 calves on two estates and achieved apparently good results 

 which, however, were brought about by the fact that simultaneously with the 

 introduction of the vaccination one cow, affected with mammary tuberculosis 

 was removed from the herd and all calves were thereafter reared upon boiled milk. 

 The only temporary character of the resistance following treatment with Tauruman 

 is shown by an experiment of Hutyra, in which a vaccinated calf received eleven 

 months after treatment an intravenous injection of 0.02 gm. of bovine bacilli 

 and died 18 days thereafter of acute miliary tuberculosis. 



3. Immunization with Avirulent Human Tubercle Bacilli (Dresden 

 Method of Klimmer). According* to Klimmer cattle may be immunized 

 for a period of one year either with human tubercle bacilli that have 

 been attenuated by heating at 52° to 53° C. or with pure cultures 

 of avirulent tubercle bacilli that have been passed through salamanders 

 (originally virulent human tubercle bacilli repeatedly passed through 

 salamanders) in the same manner as with virulent human tubercle 

 bacilli. Both of the viruses referred to are said to be nonpathogenic 

 for animals (even guinea pigs) and do not regain their pathogenicity 

 by simple passage through animals. On account of this nonpatho- 

 genicity and the fact that bacilli introduced subcutaneously into the 

 bodies of cattle are soon destroyed and completely removed, this method 

 of vaccination may be repeated every year without jeopardizing the 

 health of persons that consume the meat of animals disposed of by 

 slaughter at any time, and thus the period of immunity may be pro- 

 longed indefinitely and at will. In addition, vaccination by this method 

 is said to exert a curative influence upon already infected animals. 



Cattle twice treated with these viruses successfully resisted experimental 

 infection with virulent bovine bacilli after a period of from 2 to_ 9 months. No 

 difference was noted in the protective value of the two forms of virus. According 



