462 BIOLOGY OF PNEUMOCOCCUS 



of the disease (two days before and six days after crisis). In chil- 

 dren the reaction was demonstrable at about the same time, but 

 was negative immediately following crisis or within one or two 

 days after crisis. When the pneumonia resolved by lysis, the pa- 

 tients reacted as late as the thirty-second day. In general, the 

 test was positive in all active cases but was negative in all control 

 patients whether children or adults. Weiss and Kolmer considered 

 that the phenomenon was a manifestation of a state of allergy to 

 toxin but, since the reactivity of the skin was present during the 

 stage of toxemia and disappeared during convalescence, it is diffi- 

 cult to look upon the reaction as being strictly allergic in nature, 

 at least in so far as toxin is concerned. 



Bigelow (1922), 115 employing saline and aqueous autolysates of 

 pneumococci as antigens, succeeded in evoking type-specific dermal 

 reactions in some cases, while in others and in normal controls a 

 reaction occurred differing in character from that resulting when 

 the type of autolysate and of the infecting organism were homolo- 

 gous. Larson (1926) 787 also reported irregular results of skin 

 tests obtained in normal persons and pneumonia patients injected 

 with pneumococcal filtrates. He apparently assumed that the reac- 

 tion was due to toxin since allergy was not mentioned in the com- 

 munication. 



The question became somewhat more confused by the observa- 

 tions of Herrold and Traut (1927). 637 The majority of pneu- 

 monia patients reacted negatively to filtrates of broth cultures of 

 Pneumococcus, whereas nearly all normal individuals similarly 

 tested also gave negative reactions. By repeated tests on pneu- 

 monia patients it was found that the condition preventing a reac- 

 tion developed early in the disease and usually persisted through- 

 out convalescence. The reactive ability of the individual corre- 

 sponded to the capacity of the serum to neutralize the active prin- 

 ciple of the filtrate, the serum of a non-reactive subject usually 

 effecting a partial or complete inhibition of the antigen. 



Comparable to the results of Herrold and Traut were those of 



