Elaine Cloutman-Green1, Vera L Barbosa2, Diego Jimenez3, Daniel Wong4, Helen Dunn5, Brian Needham6, Lena Ciric3, John C Hartley5. 1. Department of Microbiology, Virology, and Infection Prevention Control, Great Ormond Street Hospital NHS Foundation Trust, London, United Kingdom; Department of Civil, Environmental, and Geomatic Engineering, University College London, London, United Kingdom. Electronic address: elaine.cloutman-green@gosh.nhs.uk. 2. Department of Flood and Coastal Risk Management, Environment Agency, Brampton, Cambridgeshire, United Kingdom. 3. Department of Civil, Environmental, and Geomatic Engineering, University College London, London, United Kingdom. 4. Department of Geography, King's College London, London, United Kingdom. 5. Department of Microbiology, Virology, and Infection Prevention Control, Great Ormond Street Hospital NHS Foundation Trust, London, United Kingdom. 6. Department of Estates and Facilities, Great Ormond Street Hospital NHS Foundation Trust, London, United Kingdom.
Abstract
BACKGROUND: Hospital-acquired Legionnaires' disease is associated with the presence of Legionella pneumophila in hospital water systems. In the United Kingdom, the Department of Health recommends maintaining hot water temperatures >55°C and cold water temperatures <20°C at the point of delivery to prevent proliferation of L pneumophila in water systems. In this study, we evaluated the efficacy of copper and silver ionization to control L pneumophila at deliberately reduced hot water temperatures (43°C) within a newly installed water system in a new building linked to a large health care facility in the United Kingdom. METHODS: One thousand, five hundred ninety-eight water samples were collected between September 2011 and June 2017. Samples were tested using accredited methods for L pneumophila, copper and silver ion levels, and total viable counts. Energy consumption and water usage data were also collected to permit carbon emission calculations. RESULTS: The results of 1,598 routine samples from September 2011 to June 2017, and the recordings of temperatures at outlets in this facility, demonstrated effective (100%) L pneumophila control throughout the study period with an average hot water temperature of 42°C. The energy savings and reduction of carbon emissions were calculated to amount to 33% and 24%, respectively, compared to an equivalent temperature-controlled system. Water system management interventions were required to achieve consistently adequate levels of copper and silver across outlets. CONCLUSIONS: This study demonstrated that it is possible to control L pneumophila independent of temperature when copper and silver ionization is introduced into a new building in conjunction with an appropriately managed water system.
BACKGROUND: Hospital-acquired Legionnaires' disease is associated with the presence of Legionella pneumophila in hospital water systems. In the United Kingdom, the Department of Health recommends maintaining hot water temperatures >55°C and cold water temperatures <20°C at the point of delivery to prevent proliferation of L pneumophila in water systems. In this study, we evaluated the efficacy of copper and silverionization to control L pneumophila at deliberately reduced hot water temperatures (43°C) within a newly installed water system in a new building linked to a large health care facility in the United Kingdom. METHODS: One thousand, five hundred ninety-eight water samples were collected between September 2011 and June 2017. Samples were tested using accredited methods for L pneumophila, copper and silver ion levels, and total viable counts. Energy consumption and water usage data were also collected to permit carbon emission calculations. RESULTS: The results of 1,598 routine samples from September 2011 to June 2017, and the recordings of temperatures at outlets in this facility, demonstrated effective (100%) L pneumophila control throughout the study period with an average hot water temperature of 42°C. The energy savings and reduction of carbon emissions were calculated to amount to 33% and 24%, respectively, compared to an equivalent temperature-controlled system. Water system management interventions were required to achieve consistently adequate levels of copper and silver across outlets. CONCLUSIONS: This study demonstrated that it is possible to control L pneumophila independent of temperature when copper and silverionization is introduced into a new building in conjunction with an appropriately managed water system.
Authors: Michele Totaro; Anna Laura Costa; Lorenzo Frendo; Sara Profeti; Beatrice Casini; Antonio Gallo; Gaetano Privitera; Angelo Baggiani Journal: Int J Environ Res Public Health Date: 2020-09-26 Impact factor: 3.390