The Action of Pasteurella pestis Bacteriophage on Strains of Pasteurella, Salmonella , and Shigella

Abstract

The phage used was isolated originally from a clinical case of bubonic plague, and it lysed all the strains of P. pestis that were tested. 27 strains of P. pseudotuberculosis were investigated for sensitivity to this phage, both before and after adaptation to P. pseudotuberculosis. 19 were lysed in varying degree, and were definitely more susceptible to the adapted phage. There was no evidence of lysogenic strains. Other Pasteurella spp. tested were not susceptible. 3 out of 42 Salmonella strains, and 6 out of 37 Shigella cultures were susceptible. The action of the phage was shown to be independent of the age, species, or state of dissociation of the cultures studied. After adaptation to a particular Shigella species the phage showed an increased ability to lyse the sensitive Shigella strains, and it also retained completely its ability to lyse P. pestis. 77 other cultures were tested, none of which was lysed by this phage. Antigenic relationship and sensitivity to phage were compared, and minor serologieal relationships were demonstrated between P. pestis and the susceptible Shigella strains. It is suggested that lysates of P. pestis might be used as vaccines.