266 A MANUAL OF BACTERIOLOGY 



The writer has employed endotoxin solutions as vaccines and 

 believes they are very efficient. 



So-called " detoxicated vaccines " are on the market. The 

 mode of preparation has not been clearly described. They are 

 supposed to give rise to little or no reaction. 



Prophylactic vaccines. In addition to the therapeutic vaccines 

 for the treatment of the declared disease, vaccines are also employed 

 for prevention of disease. The preventive or prophylactic vaccines 

 may be : 



(1) Living, but attenuated, cultures, e.g. anthrax and cholera. 

 This method has also been proposed for plague, typhoid fever and 

 others. Vaccinia must be regarded as being of this nature (this 

 is the " Pasteurian method "). 



(2) Killed cultures, autolysed cultures, and endo toxins. The 

 first and second are used for typhoid, plague and dysentery, and 

 Hewlett has suggested endotoxins for typhoid, cholera, plague 

 and diphtheria. Castellani has introduced mixed bacterial 

 vaccines, as, for example, the well : known T. A. B. vaccine against 

 typhoid-paratyphoid A and B infections. 



(3) Besredka has suggested " sensitised vaccines," i.e. cultures 

 saturated with the homologous immune body derived from an 

 immune serum. Some sensitised vaccines are now upon the 

 market. The sensitised streptococcic vaccine frequently acts 

 very satisfactorily in septic wounds with a streptococcic infection. 



Immune sera also give protection for a limited time. 

 (For further particulars, see Hewlett's Serum Therapy, ed. 2, 

 J. and A. Churchill, 1910.) 



