Legionella contamination of a cold-water supplying system in a German university hospital – assessment of the superheat and flush method for disinfection
Vol. 62 No. 3 (2021), Hospital Hygiene
Vol. 62 No. 3 (2021)

Legionella contamination of a cold-water supplying system in a German university hospital – assessment of the superheat and flush method for disinfection: Heat and flush disinfection for legionella contamination

Hospital Hygiene
https://doi.org/10.15167/2421-4248/jpmh2021.62.3.1944
Published 2021-10-15
Matthias Unterberg
Department of Anesthesiology, Intensive Care and Pain Medicine, University Hospital Knappschaftskrankenhaus Bochum, In der Schornau 23-25, 44892 Bochum, Germany
https://orcid.org/0000-0002-1500-1984
Tim Rahmel
Department of Anesthesiology, Intensive Care and Pain Medicine, University Hospital Knappschaftskrankenhaus Bochum, In der Schornau 23-25, 44892 Bochum, Germany
Thomas Kissinger
Nursing Service Management, University Hospital Knappschaftskrankenhaus Bochum, In der Schornau 23-25, 44892 Bochum, Germany
Christian Petermichl
Department of Hygiene, University Hospital Knappschaftskrankenhaus Bochum, In der Schornau 23-25, 44892 Bochum, Germany
Michael Bosmanns
Department of Hygiene, University Hospital Knappschaftskrankenhaus Bochum, In der Schornau 23-25, 44892 Bochum, Germany
Martin Niebius
Department of Hygiene, University Hospital Knappschaftskrankenhaus Bochum, In der Schornau 23-25, 44892 Bochum, Germany
Christina Schulze
Department of Hygiene, University Hospital Knappschaftskrankenhaus Bochum, In der Schornau 23-25, 44892 Bochum, Germany
Hans-Peter Jochum
Management, University Hospital Knappschaftskrankenhaus Bochum, In der Schornau 23-25, 44892 Bochum, Germany
Nina Parohl
HyKoMed GmbH, Zum Gewerbepark 9, 44532 Lünen, Germany
Michael Adamzik
Department of Anesthesiology, Intensive Care and Pain Medicine, University Hospital Knappschaftskrankenhaus Bochum, In der Schornau 23-25, 44892 Bochum, Germany
Hartmuth Nowak
Department of Anesthesiology, Intensive Care and Pain Medicine, University Hospital Knappschaftskrankenhaus Bochum, In der Schornau 23-25, 44892 Bochum, Germany
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Keywords

Legionella, hospital-acquired Legionnaires’ disease, superheat and flush, water-supplying system

Abstract

Introduction:

Legionella spp. is a potential pneumonia causing pathogen, which can be transmitted to humans from water-supplying systems. Immunocompromised but also healthy individuals can be vitally threatened. Both, hot and cold-water supplying systems must be considered as transmission sources and therefore a periodic surveillance has to be performed in public buildings according to local legislations. During a routine surveillance, a hazardous colonization was detected within the cold-water supplying system at University Hospital Knappschaftskrankenhaus Bochum, Germany. Applied architectural measures remained unsatisfying in the reduction of legionella contamination of the cold-water distributing system.

Methods:

Adapted to an analysis of risks, effort and benefit, the superheat and flush procedure was applied twice with a time interval of 6 months. Results were evaluated concerning the efficiency and the sustainability and statistically analyzed.

Results:

While 33 out of 70 samples had a higher legionella count than the legal threshold of 100 CFU/100 mL (CFU - Colony Forming Units) before the first disinfection was carried out, this number could be reduced to 1 out of 202 samples after the first intervention. Additionally, in contrast to previously published studies, the effect was long-lasting, as no relevant limit exceedance occurred during the following observation period of more than two years.

Conclusion:

The superheat and flush disinfection can provide an economic and highly effective measure in case of legionella contamination and should be shortlisted for an eradication attempt of affected water-supplying systems in hospitals.

https://doi.org/10.15167/2421-4248/jpmh2021.62.3.1944
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