Host-range modifications of bacteriophage epsilon 15

Host-range modifications were observed after multiplication of bacteriophage epsilon 15 on Salmonella strains belonging to five serovars. The phage preparations obtained were tested at RTD (routine test dilution) on strains belonging to the same serovars. In each serovar, three kinds of reaction patterns were observed: (a) specific sensitivity only to the phage multiplied on the same serovar; (b) sensitivity to all host-range modifications of the phage; (c) lack of sensitivity to all phage preparations, at RTD.