scholarly journals Efficient cooling tower operation at alkaline pH for the control of Legionella pneumophila and other pathogenic genera

2021 ◽  
pp. 117047
Author(s):  
I.S.M. Pinel ◽  
P.M. Hankinson ◽  
D.H. Moed ◽  
L.J. Wyseure ◽  
J.S. Vrouwenvelder ◽  
...  
Keyword(s):  
Legionella Pneumophila ◽  
Cooling Tower ◽  
Alkaline Ph

scholarly journals A cluster of Legionnaires' disease in Belgium linked to a cooling tower, August–September 2016: practical approach and challenges

2019 ◽  
Vol 147 ◽  
Author(s):  
N. Hammami ◽  
V. Laisnez ◽  
I. Wybo ◽  
D. Uvijn ◽  
C. Broucke ◽  
...  
Keyword(s):  
Legionella Pneumophila ◽  
Cooling Tower ◽  
Geographical Information ◽  
Cluster Management ◽  
Respiratory Sample ◽  
Health Authorities ◽  
Public Health Authorities ◽  
Legionnaires Disease ◽  
Environmental Sample Analysis

Abstract A cluster of Legionnaires' disease (LD) with 10 confirmed, three probable and four possible cases occurred in August and September 2016 in Dendermonde, Belgium. The incidence in the district was 7 cases/100 000 population, exceeding the maximum annual incidence in the previous 5 years of 1.5/100 000. Epidemiological, environmental and geographical investigations identified a cooling tower (CT) as the most likely source. The case risk around the tower decreased with increasing distance and was highest within 5 km. Legionella pneumophila serogroup 1, ST48, was identified in a human respiratory sample but could not be matched with the environmental results. Public health authorities imposed measures to control the contamination of the CT and organised follow-up sampling. We identified obstacles encountered during the cluster investigation and formulated recommendations for improved LD cluster management, including faster coordination of teams through the outbreak control team, improved communication about clinical and environmental sample analysis, more detailed documentation of potential exposures obtained through the case questionnaire and earlier use of a geographical information tool to compare potential sources and for hypothesis generation.

scholarly journals Legionnaires' disease and the sick-building syndrome

1989 ◽  
Vol 103 (2) ◽  
pp. 285-292 ◽  
Author(s):  
M. O'Mahony ◽  
A. Lakhani ◽  
A. Stephens ◽  
J. G. Wallace ◽  
E. R. Youngs ◽  
...  
Keyword(s):  
Legionella Pneumophila ◽  
Local Community ◽  
Cooling Tower ◽  
Case Control Study ◽  
Sick Building Syndrome ◽  
Air Conditioning System ◽  
Sick Building ◽  
Air Intake ◽  
Legionnaires Disease ◽  
Control Study

SUMMARYIn October 1985, six cases of legionnaires' disease were associated with a police headquarters building. Four were amongst staff who worked in or visited the communications wing of the headquarters and two cases occurred in the local community. A case-control study implicated the operations room of the communications wing as the main area associated with infection. This wing was air-conditioned and smoke tracer studies showed that drift from the exhaust as well as from the base of the cooling tower entered the main air-intake which serviced the air-conditioning system.Legionella pneumophilaserogroup 1 subgroup pontiac was isolated from water and sludge in the cooling tower pond. Contaminated drift from the top of the cooling tower was probably responsible for the two community cases. An additional discovery was that symptoms suggestive of the sick-building syndrome were associated with working in this wing.

scholarly journals Integrated Real-Time PCR for Detection and Monitoring of Legionella pneumophila in Water Systems

2006 ◽  
Vol 73 (5) ◽  
pp. 1452-1456 ◽  
Author(s):  
Diaraf Farba Yaradou ◽  
Sylvie Hallier-Soulier ◽  
Sophie Moreau ◽  
Florence Poty ◽  
Yves Hillion ◽  
...  
Keyword(s):  
Real Time ◽  
Legionella Pneumophila ◽  
Cooling Tower ◽  
Water System ◽  
Culture Method ◽  
Hot Water ◽  
Pcr Assay ◽  
Standard Culture ◽  
Serial Samples ◽  
Over Time

ABSTRACT We evaluated a ready-to-use real-time quantitative Legionella pneumophila PCR assay system by testing 136 hot-water-system samples collected from 55 sites as well as 49 cooling tower samples collected from 20 different sites, in parallel with the standard culture method. The PCR assay was reproducible and suitable for routine quantification of L. pneumophila. An acceptable correlation between PCR and culture results was obtained for sanitary hot-water samples but not for cooling tower samples. We also monitored the same L. pneumophila-contaminated cooling tower for 13 months by analyzing 104 serial samples. The culture and PCR results were extremely variable over time, but the curves were similar. The differences between the PCR and culture results did not change over time and were not affected by regular biocide treatment. This ready-to-use PCR assay for L. pneumophila quantification could permit more timely disinfection of cooling towers.

scholarly journals Isolation of Legionella pneumophila from cooling tower

1981 ◽  
Vol 55 (6) ◽  
pp. 439-446
Author(s):  
Atsushi SAITO ◽  
Naomi ITO ◽  
Hikaru TANAKA ◽  
Yoshiteru SHIGENO ◽  
Kiyo FUJITA ◽  
...  
Keyword(s):  
Legionella Pneumophila ◽  
Cooling Tower

scholarly journals Quantitative Real-Time Legionella PCR for Environmental Water Samples: Data Interpretation

2006 ◽  
Vol 72 (4) ◽  
pp. 2801-2808 ◽  
Author(s):  
Philippe Joly ◽  
Pierre-Alain Falconnet ◽  
Janine André ◽  
Nicole Weill ◽  
Monique Reyrolle ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Legionella Pneumophila ◽  
Cooling Tower ◽  
Water System ◽  
Data Interpretation ◽  
Environmental Water ◽  
Hot Water ◽  
Rrna Gene ◽  
Conventional Culture

ABSTRACT Quantitative Legionella PCRs targeting the 16S rRNA gene (specific for the genus Legionella) and the mip gene (specific for the species Legionella pneumophila) were applied to a total of 223 hot water system samples (131 in one laboratory and 92 in another laboratory) and 37 cooling tower samples (all in the same laboratory). The PCR results were compared with those of conventional culture. 16S rRNA gene PCR results were nonquantifiable for 2.8% of cooling tower samples and up to 39.1% of hot water system samples, and this was highly predictive of Legionella CFU counts below 250/liter. PCR cutoff values for identifying hot water system samples containing >103 CFU/liter legionellae were determined separately in each laboratory. The cutoffs differed widely between the laboratories and had sensitivities from 87.7 to 92.9% and specificities from 77.3 to 96.5%. The best specificity was obtained with mip PCR. PCR cutoffs could not be determined for cooling tower samples, as the results were highly variable and often high for culture-negative samples. Thus, quantitative Legionella PCR appears to be applicable to samples from hot water systems, but the positivity cutoff has to be determined in each laboratory.

scholarly journals Legionnaires' disease outbreak in Rome, Italy

2005 ◽  
Vol 133 (5) ◽  
pp. 853-859 ◽  
Author(s):  
M. C. ROTA ◽  
G. PONTRELLI ◽  
M. SCATURRO ◽  
A. BELLA ◽  
A. R. BELLOMO ◽  
...  
Keyword(s):  
Legionella Pneumophila ◽  
Cooling Tower ◽  
Case Control Study ◽  
Hospital Admissions ◽  
Case Control ◽  
Phenotypic Analysis ◽  
Single Strain ◽  
Increased Risk ◽  
Legionnaires Disease ◽  
Control Study

Between August and October 2003, 15 cases of Legionnaires' disease were detected in the 9th district of Rome. To identify possible sources of Legionella exposure, a matched case-control study was conducted and environmental samples were collected. Hospital discharge records were also retrospectively analysed for the period July–November 2003, and results were compared with the same period during the previous 3 years. The case-control study revealed a significantly increased risk of disease among those frequenting a specific department store in the district (OR 9·8, 95% CI 2·1–46·0), and Legionella pneumophila was isolated from the store's cooling tower. Genotypic and phenotypic analysis of human and environmental isolates demonstrated that the cluster was caused by a single strain of L. pneumophila serogroup 1, and that the cooling tower of the store was the source of infection. The increased number of hospital admissions for microbiologically undiagnosed pneumonia during the study period may indicate that some legionellosis cases were not identified.

Development of an improved PCR–ICT hybrid assay for direct detection of Legionellae and Legionella pneumophila from cooling tower water specimens

2006 ◽  
Vol 40 (11) ◽  
pp. 2221-2229 ◽  
Author(s):  
Yu-Tze Horng ◽  
Po-Chi Soo ◽  
Bin-Jon Shen ◽  
Yu-Li Hung ◽  
Kai-Yin Lo ◽  
...  
Keyword(s):  
Legionella Pneumophila ◽  
Cooling Tower ◽  
Direct Detection

scholarly journals Isolation of Legionella pneumophila from the UOEH Cooling Tower

1986 ◽  
Vol 8 (4) ◽  
pp. 423-428
Author(s):  
Yoshihiko NIKAIDO ◽  
Hiroyuki KIKUHARA ◽  
Shin-ichi YOSHIDA ◽  
Yasuo MIZUGUCHI ◽  
Tadao TANABE
Keyword(s):  
Legionella Pneumophila ◽  
Cooling Tower

Comparison of Legiolert and a Conventional Culture Method for Detection of Legionella pneumophila from Cooling Towers in Québec

2019 ◽  
Vol 102 (4) ◽  
pp. 1235-1240 ◽  
Author(s):  
Isabelle Barrette
Keyword(s):  
Legionella Pneumophila ◽  
Cooling Tower ◽  
Test Procedure ◽  
Agar Plate ◽  
Culture Method ◽  
Most Probable Number ◽  
Cooling Towers ◽  
Plate Method ◽  
Probable Number ◽  
Compliance Testing

Abstract Background: Legionnaires’ disease is a potentially lethal pneumonia contracted through inhalation of aerosolized water contaminated with Legionella bacteria. Detection and control of L. pneumophila, the primary species responsible for the disease, is critical to public health. In Québec, cooling towers and evaporative condensers are required to follow a maintenance and testing program to ensure L. pneumophila concentrations remain at acceptable levels. Objective: This study compared a new culture method based on the most probable number approach, Legiolert®, with the formal culture method used at EnvironeX for regulatory compliance testing to quantify L. pneumophila from cooling tower waters in Québec. Methods: A split-sample analysis was performed in which 401 samples from cooling towers in Québec were tested with both methods. Results: Results with 74 positive samples showed that Legiolert provided a significant increase in sensitivity for L. pneumophila compared with the agar plate method. Cooling tower samples often contain non-Legionella flora that necessitate multiple treatment and plating conditions to prevent interference with the test. Legiolert showed little to no impact from non-Legionella organisms in this study. Conclusions: Overall, Legiolert showed several advantages over the agar plate method, including increased sensitivity, reduced interference, a simplified test procedure, and an easy-to-read positive signal.

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