scholarly journals Environmental Surveillance of Legionellosis within an Italian University Hospital. Results of 15 Years of Analysis

2019 ◽  
Author(s):  
Pasqualina Laganà ◽  
Alessio Facciolà ◽  
Roberta Palermo ◽  
Santi Delia
Keyword(s):  
Potential Risk ◽  
Water Samples ◽  
Continuous Monitoring ◽  
Water System ◽  
Water Systems ◽  
Hot Water ◽  
University Hospital ◽  
Source Water ◽  
Environmental Surveillance ◽  
Standard Procedures

Legionnaires’ disease is normally acquired by inhalation of legionellae from a contaminated environmental source. Water systems of large buildings, such as hospitals, are often contaminated with legionellae and therefore represent a potential risk for the hospital population. In this study, we demonstrated the constant presence of Legionella in water samples from the water system of a large university hospital in Messina (Sicily, Italy) consisting of 11 separate pavilions during a period of 15 years (2004-2018). In total, 1346 hot water samples were collected between January 2004 and December 2018. During this period, to recover Legionella spp. from water samples the standard procedures reported by the Italian Guidelines emanated in 2000 were adopted; from May 2015 to 2018 Italian Guidelines revised in 2015 (ISS, 2015), were used. The most water samples (72%) were positive to L. pneumophila serogroups 2-14 whereas L. pneumophila serogroup 1 accounted for the 18% and Legionella spp. for the 15%. Most of the positive samples were found in the buildings where are situated critical wards as ICU, Neurosurgery, Surgeries, Pneumology and Neonatal Intensive Unit Care. We highlighted the importance of a continuous monitoring of hospital water samples to prevent the potential risk of nosocomial legionellosis.

scholarly journals Environmental Surveillance of Legionellosis within an Italian University Hospital—Results of 15 Years of Analysis

2019 ◽  
Vol 16 (7) ◽  
pp. 1103 ◽  
Author(s):  
Pasqualina Laganà ◽  
Alessio Facciolà ◽  
Roberta Palermo ◽  
Santi Delia
Keyword(s):  
Potential Risk ◽  
Legionella Pneumophila ◽  
Water Samples ◽  
Continuous Monitoring ◽  
Water System ◽  
Hot Water ◽  
University Hospital ◽  
Environmental Surveillance ◽  
Standard Procedures ◽  
Legionnaires Disease

Legionnaires’ disease is normally acquired by inhalation of legionellae from a contaminated environmental source. Water systems of large and old buildings, such as hospitals, can be contaminated with legionellae and therefore represent a potential risk for the hospital population. In this study, we demonstrated the constant presence of Legionella in water samples from the water system of a large university hospital in Messina (Sicily, Italy) consisting of 11 separate pavilions during a period of 15 years (2004–2018). In total, 1346 hot water samples were collected between January 2004 and December 2018. During this period, to recover Legionella spp. from water samples, the standard procedures reported by the 2000 Italian Guidelines were adopted; from May 2015 to 2018 Italian Guidelines revised in 2015 (ISS, 2015) were used. Most water samples (72%) were positive to L. pneumophila serogroups 2–14, whereas L. pneumophila serogroup 1 accounted for 18% and non-Legionella pneumophila spp. Accounted for 15%. Most of the positive samples were found in the buildings where the following critical wards are situated: (Intensive Care Unit) ICU, Neurosurgery, Surgeries, Pneumology, and Neonatal Intensive Unit Care. This study highlights the importance of the continuous monitoring of hospital water samples to prevent the potential risk of nosocomial legionellosis.

scholarly journals From Outbreak to Compliance and Beyond: UAB Medicine’s Successful Implementation of a Water Safety Program

2020 ◽  
Vol 41 (S1) ◽  
pp. s479-s479
Author(s):  
Shatha Salah ◽  
Rachael A. Lee ◽  
Bernard Camins ◽  
Frank Sidari
Keyword(s):  
Risk Assessment ◽  
Water Samples ◽  
Water System ◽  
Water Systems ◽  
Hot Water ◽  
Physical Factors ◽  
Successful Implementation ◽  
Control Points ◽  
Water Safety ◽  
Distal Site

Background: Pre-emptive management of the water supply can reduce hospital-onset legionellosis associated with building water systems. In 2014, an outbreak of Legionella pneumonia occurred in a 1,150-bed academic medical center (with ∼0.557 km2 or ∼6 million ft2 of space) among hematology-oncology patients. A comprehensive water safety and management program was implemented after the outbreak was controlled. We describe our experience implementing this prevention program. Methods: After the Legionella outbreak was controlled, an air and water safety committee (AWSC) was established and cochaired by the healthcare epidemiologist and the chief facilities officer. The AWSC established protocols for proactive environmental testing and the development of the an infection control risk assessment (ICRA) dedicated to water safety known as the water system construction and renovation risk assessment (WSCRRA).The water system management plan (WSMP) was developed (prior to the publication of ASHRAE 188) to direct the risk assessments and mitigation of any risks throughout the campus. Results: The WSMP identifies critical control measures, points, and limits that need to be maintained to control and monitor Legionella growth in the water systems. A control point is any step in a process at which biological, chemical, or physical factors can be controlled. The UAB Medicine WSMP includes 7 control points that are monitored on a daily basis. Examples of these control steps include monitoring of the hot water temperatures at the water heaters and distal outlets, managing the levels of mono-chloramines and chlorines in the water system, and managing water system components. To validate the efficacy of the WSMP, >610 water samples are collected from 19 hospital buildings over a year to be tested for Legionella. The results of water testing have shown significant decrease in distal site positivity due to managing and controlling these control points. This WSMP also evaluated the efficacy of 2 different methods for disinfecting water systems on campus as a corrective measure to Legionella growth. These methods are hyperchlorination and temporary copper silver ionization; based on the culture results of the water samples collected post disinfection, WSMP data show that the copper silver ionization method was more effective than hyperchlorination in controlling Legionella growth and decreasing the distal site positivity. Conclusions: The WSMP has provided ongoing management of building water systems and proactive actions around construction and renovation projects that involve water systems to prevent healthcare-acquired legionellosis. We strongly recommend other healthcare facilities to implement a similar program to avoid outbreaks.Funding: NoneDisclosures: Rachael Anne Lee reports speaker honoraria from Prime Education, LLC.

Effect of heat flushing on the concentrations of Legionella pneumophila and other heterotrophic microbes in hot water systems of apartment buildings

1996 ◽  
Vol 42 (8) ◽  
pp. 811-818 ◽  
Author(s):  
Outi M. Zacheus ◽  
Pertti J. Martikainen
Keyword(s):  
Water Temperature ◽  
Legionella Pneumophila ◽  
Heterotrophic Bacteria ◽  
Water System ◽  
Water Systems ◽  
Hot Water ◽  
Circulating Water ◽  
Heterotrophic Microbes ◽  
Before And After ◽  
Circulating Water System

The decontamination of Legionella pneumophila and other heterotrophic microbes by heat flushing in four legionellae-positive hot water systems was studied. Before the decontamination procedure, the concentration of legionellae varied from 3.0 × 10−3 to 3.5 × 10−5 cfu/L and the hot water temperature from 43.6 to 51.5 °C. During the contamination the temperature was raised to 60–70 °C. All taps and showers were cleaned from sediments and flushed with hot water twice a day for several minutes. The decontamination lasted for 2–4 weeks. In a few weeks the heat-flushing method reduced the concentration of legionellae below the detection limit (50 cfu/L) in the hot circulating water system just before and after the heat exchanger. The high hot water temperature also decreased the viable counts of heterotrophic bacteria, fungi, and total microbial cells determined by the epifluorescent microscopy. However, the eradication of legionellae failed in a water system where the water temperature remained below 60 °C in some parts of the system. After the decontamination, the temperature of hot water was lowered to 55 °C. Thereafter, all the studied hot water systems were recolonized by legionellae within a few months, showing that the decontamination by heat flushing was temporary. Also, the contamination of other bacteria increased in a few months to the level before decontamination.Key words: legionellae, hot water system, decontamination, water temperature, heterotrophic bacteria.

Comparison between Energy Performance of Building and Investments to the Renewable Energy Sources

2014 ◽  
Vol 1020 ◽  
pp. 518-523
Author(s):  
Martin Kovac ◽  
Katarina Knizova
Keyword(s):  
Renewable Energy Sources ◽  
Water System ◽  
Energy Performance ◽  
Water Systems ◽  
Hot Water ◽  
Operating Costs ◽  
Energy Sources ◽  
Domestic Hot Water ◽  
Know How ◽  
The Subject

The subject of the paper is to calculate the energy performance of building in proposed variants. The differences in the variants are in the using of conventional and renewable sources for heating and domestic hot water system. Target of the second part of paper is to know, how much money we need to invest into the proposed variants for heating and domestic hot water systems and how much money will by the user paying for operating costs. The conclusion of the paper describes the payback periods of proposed variants.

scholarly journals Introduction of Monochloramine into a Municipal Water System: Impact on Colonization of Buildings by Legionella spp

2006 ◽  
Vol 72 (1) ◽  
pp. 378-383 ◽  
Author(s):  
Matthew R. Moore ◽  
Marsha Pryor ◽  
Barry Fields ◽  
Claressa Lucas ◽  
Maureen Phelan ◽  
...  
Keyword(s):  
Potable Water ◽  
Sampling Site ◽  
Water System ◽  
Water Source ◽  
Water Systems ◽  
Hot Water ◽  
County Government ◽  
Single Family ◽  
Pinellas County ◽  
Municipal Water

ABSTRACT Legionnaires' disease (LD) outbreaks are often traced to colonized potable water systems. We collected water samples from potable water systems of 96 buildings in Pinellas County, Florida, between January and April 2002, during a time when chlorine was the primary residual disinfectant, and from the same buildings between June and September 2002, immediately after monochloramine was introduced into the municipal water system. Samples were cultured for legionellae and amoebae using standard methods. We determined predictors of Legionella colonization of individual buildings and of individual sampling sites. During the chlorine phase, 19 (19.8%) buildings were colonized with legionellae in at least one sampling site. During the monochloramine phase, six (6.2%) buildings were colonized. In the chlorine phase, predictors of Legionella colonization included water source (source B compared to all others, adjusted odds ratio [aOR], 6.7; 95% confidence interval [CI], 2.0 to 23) and the presence of a system with continuously circulating hot water (aOR, 9.8; 95% CI, 1.9 to 51). In the monochloramine phase, there were no predictors of individual building colonization, although we observed a trend toward greater effectiveness of monochloramine in hotels and single-family homes than in county government buildings. The presence of amoebae predicted Legionella colonization at individual sampling sites in both phases (OR ranged from 15 to 46, depending on the phase and sampling site). The routine introduction of monochloramine into a municipal drinking water system appears to have reduced colonization by Legionella spp. in buildings served by the system. Monochloramine may hold promise as community-wide intervention for the prevention of LD.

scholarly journals Multiple Types of Legionella pneumophilaSerogroup 6 in a Hospital Heated-Water System Associated with Sporadic Infections

1999 ◽  
Vol 37 (7) ◽  
pp. 2189-2196 ◽  
Author(s):  
Paolo Visca ◽  
Paola Goldoni ◽  
P. Christian Lück ◽  
Jürgen H. Helbig ◽  
Lorena Cattani ◽  
...  
Keyword(s):  
Legionella Pneumophila ◽  
Water Samples ◽  
Water System ◽  
Hot Water ◽  
Control Measures ◽  
Hospital Environment ◽  
Modes Of Transmission ◽  
Sequence Of Events ◽  
Single Clone ◽  
Arbitrarily Primed Pcr

Five sporadic cases of nosocomial Legionnaires’ disease were documented from 1989 to 1997 in a hospital in northern Italy. Two of them, which occurred in a 75-year-old man suffering from ischemic cardiopathy and in an 8-year-old girl suffering from acute leukemia, had fatal outcomes. Legionella pneumophila serogroup 6 was isolated from both patients and from hot-water samples taken at different sites in the hospital. These facts led us to consider the possibility that a single clone of L. pneumophila serogroup 6 had persisted in the hospital environment for 8 years and had caused sporadic infections. Comparison of clinical and environmental strains by monoclonal subtyping, macrorestriction analysis (MRA), and arbitrarily primed PCR (AP-PCR) showed that the strains were clustered into three different epidemiological types, of which only two types caused infection. An excellent correspondence between the MRA and AP-PCR results was observed, with both techniques having high discriminatory powers. However, it was not possible to differentiate the isolates by means of ribotyping and analysis of rrnoperon polymorphism. Environmental strains that antigenically and chromosomally matched the infecting organism were present at the time of infection in hot-water samples taken from the ward where the patients had stayed. Interpretation of the temporal sequence of events on the basis of the typing results for clinical and environmental isolates enabled the identification of the ward where the patients became infected and the modes of transmission of Legionellainfection. The long-term persistence in the hot-water system of different clones of L. pneumophila serogroup 6 indicates that repeated heat-based control measures were ineffective in eradicating the organism.

Hospital Characteristics Associated With Colonization of Water Systems byLegionellaand Risk of Nosocomial Legionnaires' Disease: A Cohort Study of 15 Hospitals

1999 ◽  
Vol 20 (12) ◽  
pp. 798-805 ◽  
Author(s):  
Jacob L. Kool ◽  
David Bergmire-Sweat ◽  
Jay C. Butler ◽  
Ellen W. Brown ◽  
Deborah J. Peabody ◽  
...  
Keyword(s):  
Drinking Water ◽  
San Antonio ◽  
Water System ◽  
Water Systems ◽  
Hot Water ◽  
Control Measures ◽  
Chlorine Concentration ◽  
Urinary Antigen ◽  
Legionnaires Disease ◽  
Antigen Tests

AbstractObjective:To investigate an increase in reports of legionnaires' disease by multiple hospitals in San Antonio, Texas, and to study risk factors for nosocomial transmission of legionnaires' disease and determinants forLegionellacolonization of hospital hot-water systems.Setting:The 16 largest hospitals in the cities of San Antonio, Temple, and Austin, Texas.Design:Review of laboratory databases to identify patients with legionnaires' disease in the 3 years prior to the investigation and to determine the number of diagnostic tests forLegionellaperformed; measurement of hot-water temperature and chlorine concentration and culture of potable water forLegionella. Exact univariate calculations, Poisson regression, and linear regression were used to determine factors associated with water-system colonization and transmission ofLegionella.Results:Twelve cases of nosocomial legionnaires' disease were identified; eight of these occurred in 1996. The rise in cases occurred shortly after physicians started requestingLegionellaurinary antigen tests. Hospitals that frequently usedLegionellaurinary antigen tests tended to detect more cases of legionnaires' disease.Legionellawas isolated from the water systems of 11 of 12 hospitals in San Antonio; the 12th had just experienced an outbreak of legionnaires' disease and had implemented control measures. Nosocomial legionellosis cases probably occurred in 5 hospitals. The number of nosocomial legionnaires' disease cases in each hospital correlated better with the proportion of water-system sites that tested positive forLegionella (P=.07) than with the concentration ofLegionellabacteria in water samples (P=.23). Hospitals in municipalities where the water treatment plant used monochloramine as a residual disinfectant (n=4) and the hospital that had implemented control measures wereLegionella-free. The hot-water systems of all other hospitals (n=11) were colonized withLegionella. These were all supplied with municipal drinking water that contained free chlorine as a residual disinfectant. In these contaminated hospitals, the proportion of sites testing positive was inversely correlated with free residual chlorine concentration (P=.01). In all hospitals, hot-water temperatures were too low to inhibitLegionellagrowth.Conclusions:The increase in reporting of nosocomial legionnaires' disease was attributable to increased use of urinary antigen tests; prior cases may have gone unrecognized. Risk of legionnaires' disease in hospital patients was better predicted by the proportion of water-system sites testing positive forLegionellathan by the measured concentration ofLegionellabacteria. Use of monochloramine by municipalities for residual drinking water disinfection may help prevent legionnaires' disease.

scholarly journals Energy Conservation and the Promotion ofLegionella pneumophilaGrowth: The Probable Role of Heat Exchangers in a Nosocomial Outbreak

2016 ◽  
Vol 37 (12) ◽  
pp. 1475-1480 ◽  
Author(s):  
Emilie Bédard ◽  
Simon Lévesque ◽  
Philippe Martin ◽  
Linda Pinsonneault ◽  
Kiran Paranjape ◽  
...  
Keyword(s):  
Heat Exchanger ◽  
Water Samples ◽  
Heat Exchangers ◽  
Gel Electrophoresis ◽  
Water System ◽  
Pulsed Field Gel Electrophoresis ◽  
Hot Water ◽  
Nosocomial Outbreak ◽  
Hospital Acquired

OBJECTIVETo determine the source of aLegionella pneumophilaserogroup 5 nosocomial outbreak and the role of the heat exchanger installed on the hot water system within the previous year.SETTINGA 400-bed tertiary care university hospital in Sherbrooke, Canada.METHODSHot water samples were collected and cultured forL. pneumophilafrom 25 taps (baths and sinks) within wing A and 9 taps in wing B. Biofilm (5) and 2 L water samples (3) were collected within the heat exchangers forL. pneumophilaculture and detection of protists. Sequence-based typing was performed on strain DNA extracts and pulsed-field gel electrophoresis patterns were analyzed.RESULTSFollowing 2 cases of hospital-acquired legionellosis, the hot water system investigation revealed a large proportion ofL. pneumophilaserogroup 5 positive taps (22/25 in wing A and 5/9 in wing B). High positivity was also detected in the heat exchanger of wing A in water samples (3/3) and swabs from the heat exchanger (4/5). The outbreak genotyping investigation identified the hot water system as the source of infections. Genotyping results revealed that all isolated environmental strains harbored the same related pulsed-field gel electrophoresis pattern and sequence-based type.CONCLUSIONSTwo cases of hospital-acquired legionellosis occurred in the year following the installation of a heat exchanger to preheat hospital hot water. No cases were reported previously, although the sameL. pneumophilastrain was isolated from the hot water system in 1995. The heat exchanger promotedL. pneumophilagrowth and may have contributed to confirmed clinical cases.Infect. Control Hosp. Epidemiol.2016;1475–1480

scholarly journals Legionella Colonization of Hotel Water Systems in Touristic Places of Greece: Association with System Characteristics and Physicochemical Parameters

2018 ◽  
Vol 15 (12) ◽  
pp. 2707 ◽  
Author(s):  
Maria A. Kyritsi ◽  
Varvara A. Mouchtouri ◽  
Antonis Katsioulis ◽  
Elina Kostara ◽  
Vasileios Nakoulas ◽  
...  
Keyword(s):  
Water Samples ◽  
Physicochemical Parameters ◽  
Cold Water ◽  
Protective Role ◽  
Water Systems ◽  
Free Chlorine ◽  
Hot Water ◽  
Chlorine Concentration ◽  
P Value ◽  
European Guidelines

This study aimed to assess the colonization of hotel water systems in central Greece and Corfu by Legionella, and to investigate the association between physicochemical parameters and Legionella colonization. Standardized hygiene inspection was conducted in 51 hotels, and 556 water samples were analyzed for Legionella spp. Free chlorine concentration, pH, hardness, conductivity, and trace metals were defined in cold water samples. The results of inspections and chemical analyses were associated with the microbiological results using univariate and logistic regression analysis. According to the score of the checklist used for the inspections, 17.6% of the hotels were classified as satisfactory, 15.7% as adequate, and 66.7% as unsatisfactory. Moreover, 74.5% of the hotels were colonized by Legionella spp. and 31.4% required remedial measures according to the European guidelines. Legionella spp. were isolated in 28% of the samples. Unsatisfactory results of inspections were associated with Legionella presence (relative risk (RR) = 7.67, p-value = 0.043). In hot-water systems, <50 °C temperatures increased the risk of Legionella colonization (RR = 5.36, p-value < 0.001). In cold-water systems, free chlorine concentration <0.375 mg/L (odds ratio (OR) = 9.76, p-value = 0.001), pH ≥ 7.45 (OR = 4.05, p-value = 0.007), and hardness ≥321 mgCaCO3/L (OR = 5.63, p-value = 0.003) increased the risk, whereas copper pipes demonstrated a protective role (OR = 0.29, p-value = 0.0024). The majority of the hotels inspected were colonized with Legionella. Supplementary monitoring of the risk factors that were identified should be considered.

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