248 THE ACUTE PNEUMONIAS 



mixing their sera Neufeld and Haendel have insisted that 

 in the use of any anti-pneumococcic serum means should be 

 taken for ensuring that it has an antagonistic action on the 

 strain present in any particular infection. This can only be 

 done by isolating the strain and testing whether the stock serum 

 to be used can protect mice against its action. In the treatment 

 of a human case valuable time might be wasted in applying the 

 test, and the only practicable method is to employ a polyvalent 

 serum i.e., one prepared by the use in the immunisation procedure 

 of several carefully selected strains of the organism. Varied 

 opinions are held as to the therapeutic value of the treatment of 

 pneumonia by serum derived from immune animals. The use of 

 these sera apparently causes the temperature in some cases to fall, 

 and even may hasten a crisis, but further experience is necessary 

 before their value in therapeutics can be properly estimated. 



It may be stated here that vaccine therapy has been applied 

 in the treatment of pneumonia, 20 to 30 millions of a stock 

 vaccine being administered pending the preparation of an auto- 

 genous vaccine from cultures of the infecting strain made from 

 material obtained by puncture of the pneumonic lung. Need- 

 less to say, the greatest care and judgment are necessary in the 

 use of such vaccines. In certain cases there has been appar- 

 ently a good result, but in others there is no evidence that the 

 chance of survival has been greater than when ordinary treat- 

 ment is applied. Something may be said for a combined 

 treatment with serum and vaccine by the use of sensitised dead 

 bacteria on the lines already described in dealing with strepto- 

 coccic infections. Further, Rosenow has used as a vaccine 

 pneumococci from which certain toxic properties have been 

 removed by treatment with normal saline. 



There has been considerable difference of opinion as to the 

 explanations to be given of the facts observed regarding im- 

 munisation against the pneumococcus and especially regarding 

 the protective and curative properties of immune sera. There 

 is no evidence of an antitoxic action in such sera, which is in 

 accord with the absence of evidence of a specific toxin being 

 responsible for the effects of the organism on the body. In like 

 manner there is no evidence of an immune serum possessing 

 bactericidal properties comparable to what occurs in, e.g., typhoid 

 fever where immune body and complement are concerned (see 

 Immunity). Within recent times many have turned to the 

 opsonic property of sera to account for the facts observed. In 

 this connection Mennes observed that normal leucocytes only 

 become phagocytic towards pneumococci when they are lying 



