ALLERGIC REACTIONS IN TYPHOID FEVER 607 



bacillus, glanders bacillus grows evenly through the bouillon instead of upon the 

 surface. 



At the end of six or eight weeks the flasks are removed from the incubator and 

 placed in a sterilizer at 100 C. for at least two hours. This process kills the bacilli 

 and extracts the toxic principles. The entire solution is evaporated down to j^ of 

 its volume, filtered in small bottles, and sterilized. This is called concentrated mal- 

 lein, and is kept in this form until ready for use. 



Before using it is diluted to its original volume with 0.5 per cent, phenol solution, 

 and passed through a porcelain filter. This process removes all the bacilli, and ren- 

 ders the solution aseptic and ready for use. 



Ophthalmic mattein is prepared by taking one part of concentrated 

 mallein and adding 20 parts of absolute alcohol. This forms a precipi- 

 tate that is filtered and dried in a desiccator over sulphuric acid. A 

 5 per cent, solution of the powder is made with sterile water. 



Subcutaneous Mallein Reaction. The dose of mallein for a horse 

 is 0.4 c.c. of concentrated mallein, or 4 c.c. or 1 dram of the diluted 

 product. The dose for a retest is 0.8 c.c. of concentrated or 8 c.c. or 2 

 drams of the diluted solution. Mallein is injected subcutaneously in 

 some convenient area, such as around the shoulder, which has been 

 shaved and cleaned. 



A positive reaction is based on the same principle as tuberculin, 

 that is, a rise of temperature within twenty-four hours following the 

 injection, with a local inflammatory reaction at the site of injection. 



Ophthalmic Mallein Reaction. Two or three drops of the aqueous 

 solution are dropped into the inner canthus of one eye. In case of a 

 positive reaction this is followed by a marked conjunctivitis, associated 

 with a purulent exudate extending from the inner canthus similar to the 

 reaction shown in Fig. 124. In most cases there is also a rise of tempera- 

 ture. Only one dose is to be applied in the ophthalmic mallein test. 

 It is not considered necessary to sensitize the eye, as in tuberculosis. 

 The ophthalmic mallein test has the same advantages as the ophthalmic 

 tuberculin test, that is, one can obtain a reaction when dishonest horse 

 dealers have injected mallein prior to a subcutaneous mallein test, 

 also in cases of far-advanced glanders, which at times give no reaction 

 to a subcutaneous injection of mallein. 



ALLERGIC REACTIONS IN TYPHOID FEVER 



In 1907 Chantemesse 1 observed characteristic inflammatory symp- 

 toms follow the instillation of typhoid-bacilli extract into the eye of 

 1 Deut. med. Wochenschr., 1907, 33, 1572. 



