VACCINATION. IMMUNIZATION. INOCULATION 261 



hours. It consists of a purulent discharge from the eye, congestion 

 and swelling of the conjunctiva, and swelling and agglutination of 

 the eyelids. The result of the test is to be determined at the 

 twelfth hour after the instillation at the earliest, and at the twenty- 

 fourth hour at the latest. A positive reaction is a certain indica- 

 tion of the presence of glanders. On the other hand, the presence 

 of glanders is not positively excluded by a single negative reaction, 

 but only when a second test three weeks after the first also gives a 

 negative reaction. In the early stages of glanders the hypersensi- 

 tiveness to mallein is absent; it does not appear until toward the 

 second week after the infection. In doubtful cases (serous or mucous 

 discharge from the eye), the eye test sometimes gives a positive re- 

 sult when repeated on the same day (sensitization) . With a positive 

 reaction, an increase of temperature to over 38.5° C. [101. S'^ F.] usu- 

 ally occurs in 24 hours which is also of diagnostic importance. The 

 presence of fever is not a contraindication to the application of the 

 eye test. (To be preferred to the subcutaneous method.) 



In recent years, the eye test has been found to be the most 

 trustworthy, the simplest, the most convenient, the cheapest, the 

 most rapid and, for examining large numbers of horses (remounts, 

 imported horses), the most suitable method of diagnosing glanders, 

 especially in Austria, where it has been recognized by the veteri- 

 nary sanitary laws since 1910 (civil and military laws), in Denmark 

 and in Germany (Prussia, Wiirtemburg). Recently, it has been 

 officially prescribed in Bavaria. 



(b) The Subcutaneous Method or the thermal reaction con- 

 sists [in Germany] in the subcutaneous injection of 0.02 gram of 

 dry mallein or 0.5 gram of raw mallein. [In the United States, 

 the evaporated glycerin bouillon culture of bacillus mallei is 

 diluted in the laboratory with J^ per cent, carbolic acid solution, 

 and the quantity injected depends upon the extent of the dilution.] 

 A rise of temperature of over 2° C. [3.6° F.] during the two days 

 following the injection, with a typical temperature curve with 

 two apexes, is to be regarded as a positive indication of glanders, 

 while horses which do not show any febrile reaction and those with 



