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Charles N. Haas - One of the best experts on this subject based on the ideXlab platform.
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Outbreaks of Legionnaires’ Disease and Pontiac Fever 2006–2017
Current Environmental Health Reports, 2018Co-Authors: Kerry A. Hamilton, Aaron J. Prussin, Warish Ahmed, Charles N. HaasAbstract:Purpose of Review The global importance of Legionnaires’ disease (LD) and Pontiac Fever (PF) has grown in recent years. While sporadic cases of LD and PF do not always provide contextual information for evaluating causes and drivers of Legionella risks, analysis of outbreaks provides an opportunity to assess these factors. Recent Findings A review was performed and provides a summary of LD and PF outbreaks between 2006 and 2017. Of the 136 outbreaks, 115 were LD outbreaks, 4 were PF outbreaks, and 17 were mixed outbreaks of LD and PF. Cooling towers were implicated or suspected in the a large portion of LD or PF outbreaks (30% total outbreaks, 50% confirmed outbreak-associated cases, and 60% outbreak-associated deaths) over this period of time, while building water systems and pools/spas were also important contributors. Summary Potable water/building water system outbreaks seldom identify specific building water system or fixture deficiencies. The outbreak data summarized here provides information for prioritizing and targeting risk analysis and mitigation strategies.
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Outbreaks of Legionnaires’ Disease and Pontiac Fever 2006–2017
Current environmental health reports, 2018Co-Authors: Kerry A. Hamilton, Aaron J. Prussin, Warish Ahmed, Charles N. HaasAbstract:Purpose of Review The global importance of Legionnaires’ disease (LD) and Pontiac Fever (PF) has grown in recent years. While sporadic cases of LD and PF do not always provide contextual information for evaluating causes and drivers of Legionella risks, analysis of outbreaks provides an opportunity to assess these factors.
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outbreaks of legionnaires disease and Pontiac Fever 2006 2017
Current Environmental Health Reports, 2018Co-Authors: Kerry A. Hamilton, Aaron J. Prussin, Warish Ahmed, Charles N. HaasAbstract:Purpose of Review The global importance of Legionnaires’ disease (LD) and Pontiac Fever (PF) has grown in recent years. While sporadic cases of LD and PF do not always provide contextual information for evaluating causes and drivers of Legionella risks, analysis of outbreaks provides an opportunity to assess these factors.
Denis Zmirou-navier - One of the best experts on this subject based on the ideXlab platform.
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Open AccessResearch article
2015Co-Authors: Paul Tossa, Magali Deloge-abarkan, Denis Zmirou-navier, Laurence MathieuAbstract:Background: Pontiac Fever is usually described in epidemic settings. Detection of Pontiac Fever is a marker of an environmental contamination by Legionella and should thereby call for prevention measures in order to prevent outbreak of Legionnaire's disease. The objective of this study is to propose an operational definition of Pontiac Fever that is amenable to epidemiological surveillance and investigation in a non epidemic setting. Methods: A population of 560 elderly subjects residing in 25 nursing homes was followed during 4 months in order to assess the daily incidence of symptoms associated, in the literature, with Pontiac Fever. The water and aerosol of one to 8 showers by nursing home were characterized combining conventional bacterial culture of Legionella and the Fluorescence In Situ Hybridization (FISH) technique that used oligonucleotides probes specific for Legionellaceae. A definition of Pontiac Fever was devised based on clinical symptoms described in epidemic investigations and on their timing after the exposure event. The association between incidence of Pontiac Fever and shower contamination levels was evaluated to test the relevance of this definition. Results: The proposed definition of Pontiac Fever associated the following criteria: occurrence o
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Corrigendum to “Pontiac Fever among retirement home nurses associated with airborne legionella” Journal of Hospital Infection 2011; 78: 269–273
Journal of Hospital Infection, 2012Co-Authors: A. Hautemaniere, Philippe Hartemann, Thomas Remen, L. Mathieu, M. Deloge-abarkan, Denis Zmirou-navierAbstract:Corrigendum to “Pontiac Fever among retirement home nurses associated with airborne legionella” Journal of Hospital Infection 2011; 78: 269e273 A. Hautemaniere *, T. Remen , L. Mathieu , M. Deloge-Abarkan , P. Hartemann , D. Zmirou-Navier a,b Nancy University School of Medicine, Vandoeuvre-les-Nancy, France b INSERM, U954, Vandoeuvre-les-Nancy, France c EPHE (Ecole Pratique des Hautes Etudes), Laboratoire d’Hydro-climatologie Medicale Sante Environnement, Faculte de Medecine, Vandoeuvre-les-Nancy, France
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Pontiac Fever among retirement home nurses associated with airborne legionella
The Journal of hospital infection, 2011Co-Authors: A. Hautemaniere, Philippe Hartemann, Thomas Remen, L. Mathieu, M. Deloge-abarkan, Denis Zmirou-navierAbstract:The aim of this study was to ascertain incidence of symptoms compatible with Pontiac Fever (PF) and to assess their association with exposure to legionella bacteria among retirement home nurses who help residents take their shower. Within a non-epidemic framework, 104 nurses of 19 retirement homes were followed up during an average period of four months. Data on symptoms, number and location of showers they attended were recorded daily by each participant. Water and aerosol bacterial quality was characterised at the end of follow-up using the culturable and the in-situ hybridisation techniques. Among 11 Pontiac-like episodes, eight cases complied with the study definition of PF. Water concentrations >10(3) cfu legionella per litre were associated with an increased risk of PF, with dose-response patterns. No association was established between the aerosol legionella concentrations and PF events. A threshold value of 103 cfu legionella per litre of water might be used with a view to protection from legionella-associated occupational conditions.
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Legionella bacteria in shower aerosols increase the risk of Pontiac Fever among older people in retirement homes
Journal of epidemiology and community health, 2008Co-Authors: M Bauer, Paul Tossa, Philippe Hartemann, Thomas Remen, L. Mathieu, M. Deloge-abarkan, Denis Zmirou-navierAbstract:Background: 828 elderly subjects residing in nursing homes were followed up during 4 months to ascertain incidence of symptoms associated with Pontiac Fever (PF) in a non-epidemic setting. Methods: The exposure situation was inhalation of Legionella bacteria while showering. An audit of the hot water system in all institutions allowed ascribing each subject to a water quality area wherefrom one shower was sampled for Legionella assays at the end of the follow-up period. Legionella were detected in water and aerosols using the culture (CFU, colony forming units) and in situ hybridization (FISH) techniques. Results: Among 32 Pontiac-like episodes, 29 cases complied with the operational definition of PF elaborated for this study. Incidence density was 0.11 case/person–year (95% CI 0.07 to 0.15). Water concentrations greater than 105 Legionella FISH/l and 104 Legionella CFU/l were associated with an increased risk of PF (respectively RR 2.23, p = 0.05 and RR 2.39, p = 0.11, with significant dose–response patterns: p for trend Legionella FISH/l of air. A significantly higher risk of Pontiac-like episodes (RR 6.24, 95% CI 2.12 to 18.38) was seen for elderly subjects receiving corticosteroid therapy. Conclusion: The water and threshold values identified in this research could be used to inform guidance measures aimed at protecting institutionalised older people from Legionnaires’ disease. Immunosuppressive therapy in the same population group can significantly enhance susceptibility to Legionella bacteria.
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Pontiac Fever: an operational definition for epidemiological studies.
BMC public health, 2006Co-Authors: Paul Tossa, Magali Deloge-abarkan, Denis Zmirou-navier, Philippe Hartemann, Laurence MathieuAbstract:Pontiac Fever is usually described in epidemic settings. Detection of Pontiac Fever is a marker of an environmental contamination by Legionella and should thereby call for prevention measures in order to prevent outbreak of Legionnaire's disease. The objective of this study is to propose an operational definition of Pontiac Fever that is amenable to epidemiological surveillance and investigation in a non epidemic setting. A population of 560 elderly subjects residing in 25 nursing homes was followed during 4 months in order to assess the daily incidence of symptoms associated, in the literature, with Pontiac Fever. The water and aerosol of one to 8 showers by nursing home were characterized combining conventional bacterial culture of Legionella and the Fluorescence In Situ Hybridization (FISH) technique that used oligonucleotides probes specific for Legionellaceae. A definition of Pontiac Fever was devised based on clinical symptoms described in epidemic investigations and on their timing after the exposure event. The association between incidence of Pontiac Fever and shower contamination levels was evaluated to test the relevance of this definition. The proposed definition of Pontiac Fever associated the following criteria: occurrence of at least one symptom among headache, myalgia, Fever and shivers, possibly associated with other 'minor' symptoms, within three days after a shower contaminated by Legionella, during a maximum of 8 days (minimum 2 days). 23 such cases occurred during the study (incidence rate: 0.125 cases per person-year [95% CI: 0.122–0.127]). A concentration of Legionella in water equal to or greater than 104.L-1 (FISH method) was associated with a significant increase of incidence of Pontiac Fever (p = 0.04). Once validated in other settings, the proposed definition of Pontiac Fever might be used to develop epidemiological surveillance and help draw attention on sources of Legionella.
Barry S. Fields - One of the best experts on this subject based on the ideXlab platform.
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A Large, Travel-Associated Outbreak of Legionellosis among Hotel Guests: Utility of the Urine Antigen Assay in Confirming Pontiac Fever
Clinical infectious diseases : an official publication of the Infectious Diseases Society of America, 2006Co-Authors: L. J. Burnsed, Lauri A. Hicks, Laura M. K. Smithee, Barry S. Fields, Kristy K. Bradley, Neil Pascoe, Shawn Richards, Sue Mallonee, Lisa Littrell, Robert F. BensonAbstract:Background. During March 2004, a large outbreak of legionnaires disease and Pontiac Fever occurred among hotel guests in Oklahoma. An investigation was conducted to identify the source and evaluate the utility of the Legionella urine antigen assay and serologic testing for the identification of Pontiac Fever. Methods. A retrospective cohort investigation of hotel guests and employees and an environmental evaluation were performed. Participants were interviewed, and clinical specimens were collected from consenting individuals. Results. Six cases of legionnaires disease and 101 cases of Pontiac Fever were identified. Exposure to the indoor pool and hot tub area was associated with legionellosis (relative risk, 4.4; 95% confidence interval, 2.8-6.9). Specimens from the pool and hot tub tested positive for Legionella pneumophila serogroup 1 by polymerase chain reaction. For Pontiac Fever, the sensitivity and positive predictive value were 35.7% and 100%, respectively, for the urine antigen assay, and 46.4% and 90%, respectively, for serologic testing. The specificity and negative predictive value were 100% and 47.8%, respectively, for the urine antigen assay, and 89.3% and 45.5%, respectively, for serologic testing. Conclusions. Urine antigen testing, with or without serologic testing, can be used to confirm outbreak-associated cases of Pontiac Fever caused by L. pneumophila serogroup 1.
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An Outbreak of Travel-Associated Legionnaires Disease and Pontiac Fever: The Need for Enhanced Surveillance of Travel-Associated Legionellosis in the United States
The Journal of infectious diseases, 2001Co-Authors: Andrea L. Benin, Robert F. Benson, Barry S. Fields, Kathryn E. Arnold, Anthony E. Fiore, Patricia G. Cook, L. Keoki Williams, Richard E. BesserAbstract:Travel-associated outbreaks of legionnaires disease (LD) and combined outbreaks of LD and Pontiac Fever (PF) are rarely identified. During one travel-associated combined outbreak at a hotel, a cohort study of potentially exposed persons and an environmental investigation were performed. Two LD and 22 PF cases were identified. Legionella pneumophila serogroup 6 (Lp6) isolates from the index patient and the hotel whirlpool spa were found to be identical by amplified fragment-length polymorphism typing. Disease occurred in 10 of 26 guests who were exposed to the spa versus 2 of 29 guests who were exposed only to the pool area (38% vs. 7%; P = .005). Immunoglobulin M (IgM) antibody to the outbreak Lp6 strain was more common among persons with PF (4 of 9) than among non-ill persons (2 of 32) (44% vs. 6%; P= .02). Spa exposure correlated with disease (P= .001) and IgM seropositivity (P= .007). New laboratory techniques facilitate outbreak investigation; to expedite outbreak interruption and measure the impact of travel-associated legionellosis, surveillance must be improved.
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Pontiac Fever Due to Legionella micdadei from a Whirlpool Spa: Possible Role of Bacterial Endotoxin
The Journal of infectious diseases, 2001Co-Authors: Barry S. Fields, Thomas E. Haupt, Jeffrey P. Davis, Matthew J. Arduino, Phyllis H. Miller, Jay C. ButlerAbstract:During January 1998, a cluster of illnesses occurred among hotel guests in Wisconsin. Ill persons had been exposed to the hotel's whirlpool spa and swimming pool. Symptoms included headache, Fever, chills, myalgia, shortness of breath, and fatigue. A diagnosis of Pontiac Fever was made, based on serologic evidence of acute infection with Legionella micdadei. High concentrations of heterotrophic bacteria were recovered from the spa, despite apparently high disinfectant levels. L. micdadei was isolated from the swimming pool filter and water from the spa after heat enrichment but not from pools and spas at nearby hotels. Water from hotel pools and spas was tested to determine endotoxin levels; water from the spa of the implicated hotel contained the highest concentration of endotoxin (14,40() endotoxin units/mL). Additional studies are needed to determine the role of endotoxin from legionellae or other bacteria in the pathogenesis of Pontiac Fever.
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Use of Polymerase Chain Reaction in an Epidemiologic Investigation of Pontiac Fever
The Journal of infectious diseases, 1993Co-Authors: Lisa A. Miller, Robert F. Benson, James L. Beebe, Jay C. Butler, William J. Martin, Richard E. Hoffman, Barry S. FieldsAbstract:In June 1992, 13 (38%) of 34 resort guests experienced illness that met a symptom-based case definition of Pontiac Fever. Each ill guest reported using an indoor hot tub compared with 6 (29%) of 21 nonill guests (P < .001). Water samples from the indoor hot tub were culture-negative for legionellae using standard techniques, coculture with amebae, and intraperitoneal inoculation of guinea pigs. However, polymerase chain reaction (PCR) testing of the water samples indicated the presence of Legionella pneumophila. Direct fluorescent antibody testing identified the organism as serogroup 6. Seroconversion to L. pneumophila serogroup 6 occurred in 7 (64%) of 11 ill guests and none of 5 nonill guests (P = .03). These results suggest that in certain circumstances, culture of environmental samples should be supplemented with additional tests such as PCR. These results are also consistent with the concept that Pontiac Fever can be caused by nonviable legionellae.
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Virulence of a Legionella anisa strain associated with Pontiac Fever: an evaluation using protozoan, cell culture, and guinea pig models.
Infection and immunity, 1990Co-Authors: Barry S. Fields, J M Barbaree, G N Sanden, W E MorrillAbstract:Legionella anisa and the amoeba Hartmannella vermiformis were isolated from an indoor fountain implicated as the infectious reservoir in an outbreak of Pontiac Fever. We evaluated the ability of this strain of L. anisa to multiply in cultures of an amoeba (H. vermiformis), a ciliated protozoan (Tetrahymena pyriformis), and human mononuclear cells and to infect guinea pigs. These bacteria multiplied in the culture of H. vermiformis but failed to infect guinea pigs or the cultures of T. pyriformis and human mononuclear cells. These findings suggest that some Legionella spp. may multiply only in specific protozoan hosts. The inability of this strain of L. anisa to multiply in human phagocytic cells may be related to the development of Pontiac Fever rather than pneumonic legionellosis in exposed individuals. Further studies are necessary to determine whether the ability of legionellae to infect certain host cells can be correlated to differences in human disease.
Kerry A. Hamilton - One of the best experts on this subject based on the ideXlab platform.
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Outbreaks of Legionnaires’ Disease and Pontiac Fever 2006–2017
Current Environmental Health Reports, 2018Co-Authors: Kerry A. Hamilton, Aaron J. Prussin, Warish Ahmed, Charles N. HaasAbstract:Purpose of Review The global importance of Legionnaires’ disease (LD) and Pontiac Fever (PF) has grown in recent years. While sporadic cases of LD and PF do not always provide contextual information for evaluating causes and drivers of Legionella risks, analysis of outbreaks provides an opportunity to assess these factors. Recent Findings A review was performed and provides a summary of LD and PF outbreaks between 2006 and 2017. Of the 136 outbreaks, 115 were LD outbreaks, 4 were PF outbreaks, and 17 were mixed outbreaks of LD and PF. Cooling towers were implicated or suspected in the a large portion of LD or PF outbreaks (30% total outbreaks, 50% confirmed outbreak-associated cases, and 60% outbreak-associated deaths) over this period of time, while building water systems and pools/spas were also important contributors. Summary Potable water/building water system outbreaks seldom identify specific building water system or fixture deficiencies. The outbreak data summarized here provides information for prioritizing and targeting risk analysis and mitigation strategies.
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Outbreaks of Legionnaires’ Disease and Pontiac Fever 2006–2017
Current environmental health reports, 2018Co-Authors: Kerry A. Hamilton, Aaron J. Prussin, Warish Ahmed, Charles N. HaasAbstract:Purpose of Review The global importance of Legionnaires’ disease (LD) and Pontiac Fever (PF) has grown in recent years. While sporadic cases of LD and PF do not always provide contextual information for evaluating causes and drivers of Legionella risks, analysis of outbreaks provides an opportunity to assess these factors.
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outbreaks of legionnaires disease and Pontiac Fever 2006 2017
Current Environmental Health Reports, 2018Co-Authors: Kerry A. Hamilton, Aaron J. Prussin, Warish Ahmed, Charles N. HaasAbstract:Purpose of Review The global importance of Legionnaires’ disease (LD) and Pontiac Fever (PF) has grown in recent years. While sporadic cases of LD and PF do not always provide contextual information for evaluating causes and drivers of Legionella risks, analysis of outbreaks provides an opportunity to assess these factors.
Jay C. Butler - One of the best experts on this subject based on the ideXlab platform.
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Pontiac Fever Due to Legionella micdadei from a Whirlpool Spa: Possible Role of Bacterial Endotoxin
The Journal of infectious diseases, 2001Co-Authors: Barry S. Fields, Thomas E. Haupt, Jeffrey P. Davis, Matthew J. Arduino, Phyllis H. Miller, Jay C. ButlerAbstract:During January 1998, a cluster of illnesses occurred among hotel guests in Wisconsin. Ill persons had been exposed to the hotel's whirlpool spa and swimming pool. Symptoms included headache, Fever, chills, myalgia, shortness of breath, and fatigue. A diagnosis of Pontiac Fever was made, based on serologic evidence of acute infection with Legionella micdadei. High concentrations of heterotrophic bacteria were recovered from the spa, despite apparently high disinfectant levels. L. micdadei was isolated from the swimming pool filter and water from the spa after heat enrichment but not from pools and spas at nearby hotels. Water from hotel pools and spas was tested to determine endotoxin levels; water from the spa of the implicated hotel contained the highest concentration of endotoxin (14,40() endotoxin units/mL). Additional studies are needed to determine the role of endotoxin from legionellae or other bacteria in the pathogenesis of Pontiac Fever.
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Use of Polymerase Chain Reaction in an Epidemiologic Investigation of Pontiac Fever
The Journal of infectious diseases, 1993Co-Authors: Lisa A. Miller, Robert F. Benson, James L. Beebe, Jay C. Butler, William J. Martin, Richard E. Hoffman, Barry S. FieldsAbstract:In June 1992, 13 (38%) of 34 resort guests experienced illness that met a symptom-based case definition of Pontiac Fever. Each ill guest reported using an indoor hot tub compared with 6 (29%) of 21 nonill guests (P < .001). Water samples from the indoor hot tub were culture-negative for legionellae using standard techniques, coculture with amebae, and intraperitoneal inoculation of guinea pigs. However, polymerase chain reaction (PCR) testing of the water samples indicated the presence of Legionella pneumophila. Direct fluorescent antibody testing identified the organism as serogroup 6. Seroconversion to L. pneumophila serogroup 6 occurred in 7 (64%) of 11 ill guests and none of 5 nonill guests (P = .03). These results suggest that in certain circumstances, culture of environmental samples should be supplemented with additional tests such as PCR. These results are also consistent with the concept that Pontiac Fever can be caused by nonviable legionellae.