120 VACCINE AND SERUM THERAPY. 



of this serum, but when all cases are considered the results are not 

 convincing as far as the curative effects of the serum are con- 

 cerned. The reasons for the failure of a specific anti-pneumococcic 

 serum are probably dependent on the absence of an anti-toxin 

 in the serum, injection after the disease is far advanced, and the 

 difficulty in determining the species of organism causing the pneu- 

 monia. The latter reason must be evident to the clinician, because 

 the disease of lobar pneumonia may be caused by various differ- 

 ent species of organisms. Although in general, the therapeutic 

 action of anti-pneumococcic sera has not been marked, still 

 physicians who have used it in pneumonia have been impressed 

 with the general improvement of the patient, the lowering of the 

 temperature and the absence of complications, following its use. 

 Important untoward symptoms seldom have developed from its use. 

 While anti-pneumococcic serum is not definitely a curative 

 measure, the physician is warranted in using it whenever the 

 patient's condition becomes serious. In all cases it is to be 

 remembered that if beneficial results are to be obtained with 

 this serum it must be injected early. 



ANTI-TYPHOID SERUM. 



Before the discovery of the organism causing typhoid fever, 

 it was known that an attack of typhoid fever, usually gives some 

 protection against a second attack of the disease. After the 

 discovery of the typhoid bacillus it was found that animals repeat- 

 edly injected with non-fatal doses of this organism will ultimately 

 be protected against otherwise fatal doses. It was also found 

 that by injecting blood serum from immunized animals, a passive 

 immunity against typhoid bacilli can be conferred to other animals. 

 Based on these results various anti-typhoid sera have been made 

 for the specific treatment of the disease of typhoid fever in man. 



Anti-typhoid sera are usually obtained from horses which 

 have been immunized either by repeated increasing injections of 

 dead and living cultures of typhoid bacilli or typhoid bacillus 

 toxins. Most of the sera prepared have, however, not been anti- 

 toxic but anti-bacterial. Chantemesse has prepared a so-called 

 anti-toxic serum by injecting horses with increasing doses of pure 

 cultures of typhoid bacilli grown for some time on a macerated 



