52 



bodies against Pfeiffers bacillus in the serum of influenza pa- 

 tients and thus obtain information about its pathological signi- 

 ficance; (2) to look for mutual differences between the strains 

 of Pfeiffer's bacilli. It is almost entirely agglutination that has 

 been used, as this reaction is the simplest to perform and 

 gives the clearest results. The other antibody reactions have 

 hardly given any appreciable information about the classifica- 

 tion of Pfeiffer's bacillus beyond what has been obtained from 

 agglutination, and they will therefore only be incidently touched 

 upon in the following account, which will only be a summary 

 of the most important investigations and their results. 



While several workers have been unable to demonstrate any 

 specific agglutinin against^ Pfeiffer's bacillus in the blood of in- 

 fluenza patients, many others, as Levinthal (1), Neufelo & PAPA- 

 MARKU, Fromme, Sobernheim & NovAKOVic, have found a mar- 

 ked, specific production of agglutinin in a number of the patients 

 examined. Gay & Harris observed agglutination and complement 

 fixation not only in a number of influenza patients but also in 

 some of the persons who were injected with influenza vaccine 

 (containing Pfeiffer's bacillus). Duval & Harris found that the majo- 

 rity of influenza patients exhibited agglutination and later in the 

 disease, complement fixation with Pfeiffer's bacillus. 



It is however not only for Pfeiffer's bacillus that anti- 

 bodies are produced but for various other organisms found 

 in influenza. 



KoLMER, Trist, & YAGLE found agglutination and complement 

 fixation for Pfeiffer's bacillus in a number of influenza patients, 

 and to a lesser degree for Streptococcus and Micrococcus catarrhalis, 

 while Howell & Anderson more often obtained complement fixa- 

 tion with Streptococcus viridans than with Pfeiffer's bacillus. 



In testing the sera of their patients many authors have used 

 several strains of Pfeiffer's bacillus. Spooner, Scott, & Heath 

 found no difference, between the reaction of the serum against 

 the patient's own strain and foreign strains, and Lord, Scon, 

 & Nye who found complement fixation with Pfeiffers bacillus 

 in healthy carriers, obtained the same result when using a 

 monovalent or polyvalent antigen. The majority of authors 

 however state that on carrying out the tests with several strains 

 they found more or less difference between them 1 . (FCrst, 



