Legionnaires' disease: investigation of household water systems

Guidance for health protection teams on when to sample a household for legionella.


The investigation of household water systems in cases of Legionnaires’ disease: Guidance for health protection teams

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This document can assist local health protection teams (HPTs), working with environmental health departments, in the investigation of household water systems following a case of Legionnaires’ disease.

During 2020, it has been recommended that HPTs in England consider a wider scope for household water system sampling beyond the existing recommendations. Environmental sampling of relevant water systems is now encouraged for all reference laboratory-confirmed cases, regardless of whether a respiratory specimen is available.

Published 10 March 2016
Last updated 2 October 2020 + show all updates
  1. Added information about widening the scope of sampling.

  2. New guidance document for on investigation of water systems has been uploaded.

  3. First published.