SERUM THERAPY 609 



strains of streptococci, polyvalent serums which they hoped would be effective 

 against these different viruses. The results however have been disappointing. 

 Tavel's serum is prepared in a manner similar to that adopted by Marmorek 

 but passage streptococci from various sources are used for inoculation. This serum 

 is said to be only prophylactic. 



Besredka's serum. This is the anti-streptococcal serum now prepared at 

 the Pasteur Institute in Paris. 



For the preparation of the serum, Besredka uses streptococci kept in a 

 medium consisting of equal parts of Martin's broth and horse serum heated 

 to 56 C. for half-an-hour. 



In order to obtain a large quantity of growth for purposes of inoculation the 

 medium used is agar contained in Roux bottles (p. 78) which is watered with about 

 1 c.c. of horse serum before sowing the cultures. An abundant growth is obtained in 

 24 hours and this is scraped off and made into an emulsion with normal saline solution. 



Horses are immunized by intra-venous inoculation, each inoculation being made 

 with six to eight different strains of streptococci isolated from human lesions to 

 which, for purposes of standardization, a streptococcus virulent for mice or rabbits 

 is added. The streptococci are not passed through animals. The immunizing 

 process is rather tricky, each inoculation being marked by a sharp temperature 

 reaction lasting about 48 hours. Occasionally articular symptoms and inflammatory 

 phenomena develop 10 days to a fortnight after the inoculation : these symptoms 

 however rarely terminate fatally. 



The serum is not bactericidal but has considerable prophylactic and curative 

 properties. For example a mouse inoculated sub-cutaneously with ten times 

 the fatal dose of streptococci can be saved by an injection 18-24 hours later 

 of O'OOl c.c. of the serum into the peritoneal cavity. Under similar condi- 

 tions the dose for a rabbit is T5-2 c.c. 



The therapeutic value of the serum in human infections is still subjudice. 



6. Agglutination. 



Attention has already been directed to the agglutinating properties of the 

 different serums, and from what has been said it will be gathered that this 

 property is very inconstant. It not infrequently happens that a strain other 

 than that used for the preparation of a serum is more powerfully agglutinated 

 than that used for immunization. 



In culture, streptococci grow together and form large granular masses so 

 that for agglutination tests an homogeneous emulsion must be prepared. 



The serum of persons suffering from streptococcal infections has no 

 agglutinating capacity for streptococci. 



7. Bordet-Geng-ou reaction. 



[Besredka expresses the opinion that it may be possible by means of the Bordet- 

 Gengou reaction to establish a natural classification of the streptococci. In some 

 experiments carried out with Dopter he found that three streptococci from very 

 different sources all had a common fixateur : one of these streptococci was recovered 

 from a child who had died of septicaemia another from a case of erysipelas and the 

 third from a child who had died of scarlet fever. On the other hand he several 

 times found that two streptococci both isolated from the blood of the heart of a 

 case of scarlet fever reacted differently to the same fixateur. ] 



SECTION IV. THE DETECTION AND ISOLATION OF STREPTOCOCCI. 



(a) Microscopical examination. A number of films should be prepared with 

 the material (pus, blood, serous fluid, etc.) and stained, some with carbol- 

 thionin [or dilute carbol-fuchsin] and others by Gram's method. 



Tissues for sections (erysipelas skin, internal organs, etc.) should be fixed 



2Q 



