Diagnostic uses of cholera bacteriophages

Abstract

1. Apart from strain identification of V. cholerae for epidemiological studies by phage-typing and determination of their S-R dissociation cholera bacteriophages may be utilized for other valuable diagnostic aids in the laboratory.2. The universal susceptibility of V. cholerae strains to group IV cholera bacteriophage and universal lyso-resistance of El Tor vibrios to it provide a specific method for differentiating between the two species of vibrios. This test is simple and convenient for routine diagnostie use and should be of special value for identifying non-haemolytic El Tor vibrios, which are otherwise liable to be missed.3. The marked insensitivity of the NAG vibrios to cholera bacteriophages, particularly their total insusceptibility to the phage of group II, enables these strains to be readily distinguishable from V. cholerae.4. Cholera bacteriophages which are stable on maintenance and storage in the laboratory can conveniently be supplied absorbed on filter disks for the use of the smaller laboratories.