Phage typing of Vibrio cholerae using a new collection of phages.

The authors formed a collection of typing phages in order to differentiate cholera vibrios of both biotypes. The collection consists of 7 phages proposed by Mukerjee for typing vibrios of the classical biotype and 3 El Tor phages isolated at the period of the 7th pandemy of cholera. In forming the typing collection the authors observed the following principles: 1) to crate a single set of typing phages and a single scheme of phage type differentiation of classical cholera and El Tor vibrios; 2) to use virulent phages; 3) to form a collection of serologically different phage types. The proposed collection allows to reveal a larger number of phage types as compared with phages proposed by Mukerjee phage typing a larger number of strains enhancing thus the epidemiological significance of the method of phage typing cholera vibrios.