[Typing properties of bacteriophages isolated from Sh. sonnei strains]

On the basis of studying the lytic activity of eight bacteriophages the authors elaborated a scheme of bacteriophage typing of Sh. sonnei consisting of nine bacteriophage types with two subtypes. In typing 2348 strains isolated in various cities of the USSR bacteriophage pattern of Sh. sonnei was found to differ in different towns of the USSR. All the strains isolated repeatedly from the same patients were referred to the same bacteriophage type, this pointing to the stability of the type-determining properties of bacteriophages. Stability of bacteriophage types, a possibility of typing the strains of the I, II phases and of R-forms, simplicity and distinctness of the scheme of bacteriophage typing determined future prospects in using the type bacteriophages selected at the Tbilisi Institute of Vaccine and Sera for intraspecies differentiation of Sh. sonnei.