The protective value of the different types of typhoid bacteriophage in mice

1. Undoubtedly the different races of typhoid bacteriophage can give varying degrees of protection to mice2. There is parallel between the degrees of protection in mice and the virulence of bacteriophage in vitro3. Polyvalent typhoid phage which includes the 4 types gave the best protection4. The composition and the virulence of bacteriophage should be considered in the preparation and the application of typhoid bacteriophage.(Conclusions)