VACCINES IN PROPHYLAXIS OF DISEASE 211 



by the paratyphoid bacilli resembles a mild at- 

 tack of typhoid fever. 



Vaccine composed of the typhoid and paraty- 

 phoid bacilli has been used in several thousands 

 of cases and no ill effects, other than the usual 

 local reactions which follow after typhoid in- 

 oculation, have been seen. Such a combined 

 vaccine immunizes the person against the two 

 types of the paratyphoid bacilli, as well as 

 against the typhoid bacillus. In view of the fact 

 that the paratyphoid bacilli are so widely dis- 

 tributed, it would seem advisable to use the com- 

 bined vaccine for immunizing purposes, inas- 

 much as such a vaccine protects against both 

 types of the disease. 



Paratyphoid Vaccines have been studied by 

 Castellani, Cummins, Gumming, Kabeshima 

 and others. The recent work of Kabeshima af- 

 fords full evidence both from animal experi- 

 ments and from extended observations carried 

 out on the personnel of the Imperial Japanese 

 Navy of the great protective value as well as 

 the innocuous character of the paratyphoid in- 

 oculation. Kabeshima used a mixed vaccine 

 containing equal numbers of the typhoid, para- 

 typhoid "A" and paratyphoid "B" bacilli. 



