Slow growing mycobacteria: procedure for testing heater cooler units

Standard operating procedure (SOP) outlining the work processes of environmental samples for the isolation and identification of slow growing mycobacteria.


Protocol for environmental sampling, processing and culturing of water and air samples for the isolation of slow-growing mycobacteria: standard operating procedure

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This protocol provides guidance on how best to perform and process environmental water and air sampling, from heater-cooler units and environments where these units are in operation, in order to recover slow growing mycobacterial species.

The environmental samples referred to in this document are:

  • water samples from heater-cooler units (used in cardiopulmonary bypass surgery)
  • air samples in environments where heater cooler units are in operation (in support of cardiopulmonary bypass surgery)

This is an interim protocol generated as part of an incident response and will be finalised when more data is available.

New data on water sampling and culture methods for the detection of M. chimaera are available in this article in the Journal of Hospital Infection published on 21 November 2017.

Published 9 June 2015
Last updated 1 February 2018 + show all updates
  1. Added link to new data on water sampling and culture methods for the detection of M. chimaera.
  2. Added updated version of guidance, July 2016.
  3. First published.