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Updated: Jun 11, 2026
07:58
Laboratory Techniques Used to Maintain and Differentiate Biotypes of Vibrio cholerae Clinical and Environmental Isolates
Published on: May 30, 2017
Summary
A new bacteriophage-typing scheme for Vibrio cholerae was developed using cholera bacteriophages. This method effectively classified over 4000 strains, aiding in cholera outbreak investigations.
Area of Science:
- Microbiology
- Epidemiology
- Bacteriology
Background:
- Vibrio cholerae causes cholera, a significant public health concern.
- Accurate strain identification is crucial for epidemiological surveillance and control.
Purpose of the Study:
- To develop and evaluate a bacteriophage-typing scheme for Vibrio cholerae.
- To classify Vibrio cholerae strains based on their susceptibility to bacteriophages.
Main Methods:
- Utilized four groups of freshly isolated cholera bacteriophages.
- Tested the susceptibility patterns of 4066 Vibrio cholerae strains isolated in Calcutta (1955-1961).
- Classified strains into types and subtypes based on phage susceptibility.
Main Results:
- Developed a bacteriophage-typing scheme classifying strains into seven types and subtypes.
- Less than 1% of strains were untypable.
- No correlation found between phage-types and serological types, but a correlation existed between phage-types and lysogenic phages in lysogenic strains.
- Identified single phage-types causing infections from a single source.
Conclusions:
- The developed phage-typing scheme is a practical tool for epidemiological investigation of cholera.
- Phage-typing provides valuable insights into Vibrio cholerae transmission dynamics.
- The scheme aids in distinguishing sources of cholera outbreaks.
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