Legionella: detection in healthcare premises

Guidance for responding to positive counts of legionella in healthcare premises, in the absence of associated cases of Legionnaires’ disease.


Responding to the detection of legionella in healthcare premises: guidance for PHE health protection teams

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This document for Public Health England (PHE) health protection teams (HPT) provides:

  • guidance when approached by infection, prevention and control teams and estate departments on maintaining their water systems to ensure there is a consistent and appropriate response from PHE
  • information and practical guidance for HPT staff who are participating in incident control teams, or a water safety group

It describes situations where HPTs should be contacted, and the extent of involvement that can be expected of HPTs where legionella counts are detected in the hot and cold water systems (excludes cooling towers) of healthcare premises.

The guidance and accompanying algorithm (figure 1, p.10) applies to situations where there are no associated nosocomial cases, although it is possible that cases may subsequently be identified.

Published 6 August 2015
Last updated 17 December 2015 + show all updates
  1. Updated guidance, December 2015.
  2. First published.