Report No DWI0279

A REVIEW OF THE OCCURRENCE AND SIGNIFICANCE OF AEROMONADS WITH PARTICULAR REFERENCE TO POTABLE WATER DISTRIBUTION SYSTEMS

DWI0279

Aug 1991

SUMMARY

The objective of this study is to review the literature concerning the occurrence and significance of aeromonads in potable water distribution systems. Aeromonads have been frequently recovered from distribution systems where their occurrence has been considered as a measure of regrowth potential. Also, attention has focused on the group because of their potential threat to public health.

The conclusions derived from the literature review are set out as follows:

  1. The classification of the motile aeromonad group has not been satisfactorily defined. In most cases classification to genus level would be appropriate.
  2. The majority of selective media for recovery of aeromonads do not perform entirely satisfactorily.
  3. Identification of isolates would be better achieved by using a series of specific biochemical tests in preference to the commercially available API system.
  4. In natural waters the numbers of aeromonads exhibit seasonal variations which could be linked to temperature and selective utilisation of algal and macrophyte components.
  5. In potable waters aeromonads respond to an interaction between a number of factors including chlorine concentration, temperature and residence time.
  6. The link between the presence of aeromonads in drinking water and the outbreak of waterborne gastroenteritis has not been established.
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