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Leoni E, Catalani F, Marini S, Dallolio L. Legionellosis Associated with Recreational Waters: A Systematic Review of Cases and Outbreaks in Swimming Pools, Spa Pools, and Similar Environments. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2018; 15:E1612. [PMID: 30061526 PMCID: PMC6121464 DOI: 10.3390/ijerph15081612] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Revised: 07/20/2018] [Accepted: 07/25/2018] [Indexed: 12/24/2022]
Abstract
Legionella spp. is widespread in many natural and artificial water systems, such as hot water distribution networks, cooling towers, and spas. A particular risk factor has been identified in the use of whirlpools and hot tubs in spa facilities and public baths. However, there has been no systematic synthesis of the published literature reporting legionellosis cases or outbreaks related to swimming/spa pools or similar environments used for recreational purposes (hot springs, hot tubs, whirlpools, natural spas). This study presents the results of a systematic review of the literature on cases and outbreaks associated with these environments. Data were extracted from 47 articles, including 42 events (17 sporadic cases and 25 outbreaks) and 1079 cases, 57.5% of which were diagnosed as Pontiac fever, without any deaths, and 42.5% were of Legionnaires' disease, with a fatality rate of 6.3%. The results are presented in relation to the distribution of Legionella species involved in the events, clinical manifestations and diagnosis, predisposing conditions in the patients, favourable environmental factors, and quality of the epidemiological investigation, as well as in relation to the different types of recreational water sources involved. Based on the epidemiological and microbiological criteria, the strength of evidence linking a case/outbreak of legionellosis with a recreational water system was classified as strong, probable, and possible; in more than half of the events the resulting association was strong.
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Affiliation(s)
- Erica Leoni
- Unit of Hygiene, Public Health and Medical Statistics, Department of Biomedical and Neuromotor Sciences, University of Bologna, via S. Giacomo 12, 40126 Bologna, Italy.
| | - Federica Catalani
- School of Hygiene and Preventive Medicine, Department of Biomedical and Neuromotor Sciences, University of Bologna, via S. Giacomo 12, 40126 Bologna, Italy.
| | - Sofia Marini
- Department of Life Quality Studies, University of Bologna, Campus of Rimini; Corso d'Augusto 237, 47921 Rimini, Italy.
| | - Laura Dallolio
- Unit of Hygiene, Public Health and Medical Statistics, Department of Biomedical and Neuromotor Sciences, University of Bologna, via S. Giacomo 12, 40126 Bologna, Italy.
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Oana K, Kobayashi M, Yamaki D, Sakurada T, Nagano N, Kawakami Y. Applicability assessment of ceramic microbeads coated with hydroxyapatite-binding silver/titanium dioxide ceramic composite earthplus™ to the eradication of Legionella in rainwater storage tanks for household use. Int J Nanomedicine 2015; 10:4971-9. [PMID: 26346201 PMCID: PMC4531045 DOI: 10.2147/ijn.s87350] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Water environments appear to be the habitats of Legionella species. Legionellosis is considered as a preventable illness because bacterial reservoirs can be controlled and removed. Roof-harvested rainwater has attracted significant attention not only as a groundwater recharge but also as a potential alternative source of nonpotable water. We successfully developed ceramic microbeads coated with hydroxyapatite-binding silver/titanium dioxide ceramic composite earthplus™ using the thermal spraying method. The ceramic microbeads were demonstrated to have bactericidal activities against not only Legionella but also coliform and heterotrophic bacteria. Immersing the ceramic microbeads in household rainwater storage tanks was demonstrated to yield the favorable eradication of Legionella organisms. Not only rapid-acting but also long-lasting bactericidal activities of the ceramic microbead were exhibited against Legionella pneumophila. However, time-dependent attenuation of the bactericidal activities against Legionella were also noted in the sustainability appraisal experiment. Therefore, the problems to be overcome surely remain in constantly managing the Legionella-pollution by means of immersing the ceramic microbeads. The results of our investigation apparently indicate that the earthplus™-coated ceramic microbeads would become the favorable tool for Legionella measures in household rainwater storage tanks, which may become the natural reservoir for Legionella species. Our investigation would justify further research and data collection to obtain more reliable procedures to microbiologically regulate the Legionella in rainwater storage tanks.
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Affiliation(s)
- Kozue Oana
- Division of Infection Control and Microbiological Regulation, Department of Health and Medical Sciences, Shinshu University Graduate School of Medicine, Matsumoto, Japan ; Division of Clinical Microbiology, Department of Biomedical Laboratory Sciences, School of Health Sciences, Shinshu University School of Medicine, Matsumoto, Japan
| | - Michiko Kobayashi
- Division of Infection Control and Microbiological Regulation, Department of Health and Medical Sciences, Shinshu University Graduate School of Medicine, Matsumoto, Japan
| | - Dai Yamaki
- Shinshu Ceramics Co., Ltd., Kiso, Nagano, Japan
| | | | - Noriyuki Nagano
- Division of Infection Control and Microbiological Regulation, Department of Health and Medical Sciences, Shinshu University Graduate School of Medicine, Matsumoto, Japan ; Division of Clinical Microbiology, Department of Biomedical Laboratory Sciences, School of Health Sciences, Shinshu University School of Medicine, Matsumoto, Japan
| | - Yoshiyuki Kawakami
- Division of Infection Control and Microbiological Regulation, Department of Health and Medical Sciences, Shinshu University Graduate School of Medicine, Matsumoto, Japan ; Division of Clinical Microbiology, Department of Biomedical Laboratory Sciences, School of Health Sciences, Shinshu University School of Medicine, Matsumoto, Japan
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Kao PM, Hsu BM, Chang TY, Hsu TK, Tzeng KJ, Huang YL. Seasonal variation of Legionella in Taiwan's reservoir and its relationships with environmental factors. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2015; 22:6104-6111. [PMID: 25391236 DOI: 10.1007/s11356-014-3819-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2014] [Accepted: 11/03/2014] [Indexed: 06/04/2023]
Abstract
In this study, the presence of Legionella in major water reservoirs of Taiwan was examined with respect to seasonal variation, geographical variation, and water quality parameters using TaqMan real-time qPCR. Water samples were collected quarterly at 19 reservoirs in Taiwan between November 2012 and August 2013. The detection rate for Legionella was 35.5% (27/76), and Legionella was detected in all seasons. The Legionella concentration was relatively high in spring and summer, reaching 3.86 × 10(8) and 7.35 × 10(8) cells/L, respectively. By sampling the area, Legionella was detected at a higher proportion in reservoirs in the northern and southern areas, and the difference was consistent in all seasons. Significant association was found between detection of Legionella and various water quality parameters, including conductivity, chlorophyll a, and dissolved oxygen (Mann-Whitney U test, P < 0.05). Results of Spearman rank test showed negative correlation for Legionella detection with pH (P = 0.030, R = -0.497) and dissolved oxygen (P = 0.007, R = -0.596) in fall and positive correlation with Carlson's trophic state index (P = 0.049, R = 0.457) in spring. The identified species included Legionella pneumophila and Legionella drancourtii. The detection of Legionella in reservoirs was indicative of a potential public health risk and should be further evaluated.
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Affiliation(s)
- Po-Min Kao
- Department of Earth and Environmental Sciences, National Chung Cheng University, Chiayi, Taiwan, Republic of China
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Kao PM, Hsu BM, Hsu TK, Ji WT, Huang PH, Hsueh CJ, Chiang CS, Huang SW, Huang YL. Application of TaqMan fluorescent probe-based quantitative real-time PCR assay for the environmental survey of Legionella spp. and Legionella pneumophila in drinking water reservoirs in Taiwan. THE SCIENCE OF THE TOTAL ENVIRONMENT 2014; 490:416-421. [PMID: 24867705 DOI: 10.1016/j.scitotenv.2014.04.103] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Revised: 04/24/2014] [Accepted: 04/25/2014] [Indexed: 06/03/2023]
Abstract
In this study, TaqMan fluorescent quantitative real-time PCR was performed to quantify Legionella species in reservoirs. Water samples were collected from 19 main reservoirs in Taiwan, and 12 (63.2%) were found to contain Legionella spp. The identified species included uncultured Legionella spp., L. pneumophila, L. jordanis, and L. drancourtii. The concentrations of Legionella spp. and L. pneumophila in the water samples were in the range of 1.8×10(2)-2.6×10(3) and 1.6×10(2)-2.4×10(2) cells/L, respectively. The presence and absence of Legionella spp. in the reservoir differed significantly in pH values. These results highlight the importance that L. pneumophila, L. jordanis, and L. drancourtii are potential pathogens in the reservoirs. The presence of L. pneumophila in reservoirs may be a potential public health concern that must be further examined.
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Affiliation(s)
- Po-Min Kao
- Department of Earth and Environmental Sciences, National Chung Cheng University, Chiayi, Taiwan, ROC
| | - Bing-Mu Hsu
- Department of Earth and Environmental Sciences, National Chung Cheng University, Chiayi, Taiwan, ROC.
| | - Tsui-Kang Hsu
- Department of Ophthalmology, Cheng Hsin General Hospital, Taipei, Taiwan, ROC
| | - Wen-Tsai Ji
- Department of Earth and Environmental Sciences, National Chung Cheng University, Chiayi, Taiwan, ROC
| | - Po-Hsiang Huang
- Department of Earth and Environmental Sciences, National Chung Cheng University, Chiayi, Taiwan, ROC
| | - Chih-Jen Hsueh
- Department of Otorhinolaryngology, Cheng Hsin General Hospital, Taipei, Taiwan, ROC
| | - Chuen-Sheue Chiang
- Research and Diagnostic Center, Centers for Disease Control, Taiwan, ROC
| | - Shih-Wei Huang
- Center for General Education, Cheng-Shiu University, Kaohsiung, Taiwan, ROC
| | - Yu-Li Huang
- Department of Safety Health and Environmental Engineering, National Kaohsiung First University of Science and Technology, Kaohsiung, Taiwan, ROC
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Distribution of sequence-based types of legionella pneumophila serogroup 1 strains isolated from cooling towers, hot springs, and potable water systems in China. Appl Environ Microbiol 2014; 80:2150-7. [PMID: 24463975 DOI: 10.1128/aem.03844-13] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Legionella pneumophila serogroup 1 causes Legionnaires' disease. Water systems contaminated with Legionella are the implicated sources of Legionnaires' disease. This study analyzed L. pneumophila serogroup 1 strains in China using sequence-based typing. Strains were isolated from cooling towers (n = 96), hot springs (n = 42), and potable water systems (n = 26). Isolates from cooling towers, hot springs, and potable water systems were divided into 25 sequence types (STs; index of discrimination [IOD], 0.711), 19 STs (IOD, 0.934), and 3 STs (IOD, 0.151), respectively. The genetic variation among the potable water isolates was lower than that among cooling tower and hot spring isolates. ST1 was the predominant type, accounting for 49.4% of analyzed strains (n = 81), followed by ST154. With the exception of two strains, all potable water isolates (92.3%) belonged to ST1. In contrast, 53.1% (51/96) and only 14.3% (6/42) of cooling tower and hot spring, respectively, isolates belonged to ST1. There were differences in the distributions of clone groups among the water sources. The comparisons among L. pneumophila strains isolated in China, Japan, and South Korea revealed that similar clones (ST1 complex and ST154 complex) exist in these countries. In conclusion, in China, STs had several unique allelic profiles, and ST1 was the most prevalent sequence type of environmental L. pneumophila serogroup 1 isolates, similar to its prevalence in Japan and South Korea.
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Kao PM, Tung MC, Hsu BM, Chiu YC, She CY, Shen SM, Huang YL, Huang WC. Identification and quantitative detection of Legionella spp. in various aquatic environments by real-time PCR assay. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2013; 20:6128-6137. [PMID: 23536272 DOI: 10.1007/s11356-013-1534-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Accepted: 01/29/2013] [Indexed: 06/02/2023]
Abstract
In this study, a SYBR green quantitative real-time PCR was developed to quantify and detect the Legionella spp. in various environmental water samples. The water samples were taken from watershed, water treatment plant, and thermal spring area in Taiwan. Legionella was detected in 13.6 % (24/176), and the detection rate for river water, raw drinking water, and thermal spring water was 10, 21.4, and 16.6 %, respectively. Using real-time PCR, concentration of Legionella spp. in detected samples ranged between 9.75 × 10(4) and 3.47 × 10(5) cells/L in river water, 6.92 × 10(4) and 4.29 × 10(5) cells/L in raw drinking water, and 5.71 × 10(4) and 2.12 × 10(6) cells/L for thermal spring water samples. The identified species included Legionella pneumophila (20.8 %), Legionella jordanis (4.2 %), Legionella nautarum (4.2 %), Legionella sp. (4.2 %), and uncultured Legionella sp. (66.6 %). The presence of L. pneumophila in aquatic environments suggested a potential public health threat that must be further examined.
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Affiliation(s)
- Po-Min Kao
- Department of Earth and Environmental Sciences, National Chung Cheng University, Chiayi, Taiwan, Republic of China
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Qin T, Yan G, Ren H, Zhou H, Wang H, Xu Y, Zhao M, Guan H, Li M, Shao Z. High prevalence, genetic diversity and intracellular growth ability of Legionella in hot spring environments. PLoS One 2013; 8:e59018. [PMID: 23527075 PMCID: PMC3601096 DOI: 10.1371/journal.pone.0059018] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2013] [Accepted: 02/09/2013] [Indexed: 11/18/2022] Open
Abstract
Background Legionella is the causative agent of Legionnaires' disease, and hot springs are a major source of outbreaks of this disease. It is important from a public health perspective to survey hot spring environments for the presence of Legionella. Methods Prospective surveillance of the extent of Legionella pollution was conducted at three hot spring recreational areas in Beijing, China in 2011. Pulsed-field gel electrophoresis (PFGE) and sequence-based typing (SBT) were used to describe the genetic polymorphism of isolates. The intracellular growth ability of the isolates was determined by interacting with J774 cells and plating the dilutions onto BCYE agar plates. Results Overall, 51.9% of spring water samples showed Legionella-positive, and their concentrations ranged from 1 CFU/liter to 2,218 CFU/liter. The positive rates of Legionella were significantly associated with a free chlorine concentration of ≥0.2 mg/L, urea concentration of ≥0.05 mg/L, total microbial counts of ≥400 CFU/ml and total coliform of ≥3 MPN/L (p<0.01). The Legionella concentrations were significantly associated with sample temperature, pH, total microbial counts and total coliform (p<0.01). Legionella pneumophila was the most frequently isolated species (98.9%), and the isolated serogroups included serogroups 3 (25.3%), 6 (23.4%), 5 (19.2%), 1 (18.5%), 2 (10.2%), 8 (0.4%), 10 (0.8%), 9 (1.9%) and 12 (0.4%). Two hundred and twenty-eight isolates were analyzed by PFGE and 62 different patterns were obtained. Fifty-seven L. pneumophila isolates were selected for SBT analysis and divided into 35 different sequence types with 5 main clonal groups. All the 57 isolates had high intracellular growth ability. Conclusions Our results demonstrated high prevalence and genetic polymorphism of Legionella in springs in Beijing, China, and the SBT and intracellular growth assay results suggested that the Legionella isolates of hot spring environments were pathogenic. Improved control and prevention strategies are urgently needed.
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Affiliation(s)
- Tian Qin
- State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Changping, Beijing, China
- * E-mail: (TQ); (ZS)
| | - Gebin Yan
- Changping District Center for Disease Control and Prevention, Changping, Beijing, China
| | - Hongyu Ren
- State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Changping, Beijing, China
| | - Haijian Zhou
- State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Changping, Beijing, China
| | - Huanxin Wang
- Changping District Center for Disease Control and Prevention, Changping, Beijing, China
| | - Ying Xu
- Changping District Center for Disease Control and Prevention, Changping, Beijing, China
| | - Mingqiang Zhao
- Changping District Center for Disease Control and Prevention, Changping, Beijing, China
| | - Hong Guan
- State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Changping, Beijing, China
| | - Machao Li
- State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Changping, Beijing, China
| | - Zhujun Shao
- State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Changping, Beijing, China
- * E-mail: (TQ); (ZS)
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Ali S, Phillips CA, Phillips PS, Bates M. Isolation and identification of Legionella pneumophila from material reclamation facilities. INTERNATIONAL JOURNAL OF ENVIRONMENTAL HEALTH RESEARCH 2010; 20:367-377. [PMID: 20853198 DOI: 10.1080/09603123.2010.484859] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Sampling points at a material reclamation facility (MRF) were monitored over three months for the presence of Legionella spp. A number of different Legionellae were isolated and typed to identify L. pneumophila serogroup 1, the serotype which is the most common human pathogen. Phenotypic methods resulted in a total of 61 presumptive isolates of Legionella spp. Using latex agglutination, 26 out of the 61 were identified as L. pneumophila serogroup 1, 23 as L. pneumophila serogroups 2-14, and the remaining 12 were Legionella spp. However, on typing using pulse field gel electrophoresis, the 26 L. pneumophila serotype 1 isolates were a diverse group of 25 PFGE types with none persisting in the environment over time. This diversity suggests that there are a number of contamination sources for this important human pathogen in the MRF environment which constitute a risk to health for operatives in these facilities.
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Affiliation(s)
- Shanom Ali
- School of Health, University of Northampton, Northampton, UK
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Huang SW, Hsu BM, Wu SF, Fan CW, Shih FC, Lin YC, Ji DD. Water quality parameters associated with prevalence of Legionella in hot spring facility water bodies. WATER RESEARCH 2010; 44:4805-4811. [PMID: 20727568 DOI: 10.1016/j.watres.2010.07.063] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2010] [Revised: 07/08/2010] [Accepted: 07/20/2010] [Indexed: 05/29/2023]
Abstract
Some species of Legionella are recognized as opportunistic potential human pathogens, such as Legionella pneumophila, which causes legionnaires disease. Indeed, outbreaks of legionellosis are frequently reported in areas in which the organism has been spread via aerosols from contaminated institutional water systems. Contamination in hot tubs, spas and public baths are also possible. As a result, in this study, we investigated the distribution of Legionella at six hot spring recreation areas throughout Taiwan. Legionella were detected in all six hot spring recreation areas, as well as in 20 of the 72 samples that were collected (27.8%). Seven species of Legionella identified from samples by the direct DNA extraction method were unidentified Legionella spp., Legionella anisa, L. pneumophila, Legionella erythra, Legionella lytica, Legionella gresilensis and Legionella rubrilucen. Three species of Legionella identified in the samples using the culture method were L. pneumophila, unidentified Legionella spp. and L. erythra. Legionella species were found in water with temperatures ranging from 22.7 °C to 48.6 °C. The optimal pH appeared to range from 5.0 to 8.0. Taken together, the results of this survey confirmed the ubiquity of Legionella in Taiwan spring recreational areas. Therefore, a long-term investigation of the health of workers at hot spring recreational areas and the occurrence of Legionella in hot spring recreational areas throughout Taiwan are needed.
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Affiliation(s)
- Shih-Wei Huang
- Department of Earth and Environmental Sciences, National Chung Cheng University, 168 University Road, Minhsiung Township, Chiayi County 62102, Taiwan, ROC
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Optimization of pulsed-field gel electrophoresis for Legionella pneumophila subtyping. Appl Environ Microbiol 2010; 76:1334-40. [PMID: 20061458 DOI: 10.1128/aem.01455-09] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A total of 32 strains of Legionella pneumophila were used to optimize pulsed-field gel electrophoresis (PFGE) for subtyping of L. pneumophila. Twenty-six isolates of L. pneumophila with various origins and 11 isolates from five different water systems were used as the panels. For optimization of electrophoretic parameters (EPs) of SfiI PFGE, 26 isolates were analyzed with SfiI digestion, using four EPs yielding the same D value. The EP of a switch time of 5 to 50 s for 21 h had the smallest similarity coefficients and was declared the optimal EP for SfiI PFGE of L. pneumophila. By software analysis and pilot study, AscI was chosen as another PFGE enzyme. AscI PFGE could cluster the isolates from each water system into the same or very similar patterns and had a high degree of typing concordance with other molecular methods. In evaluating the discriminatory power of AscI with the panel of 26 isolates, AscI PFGE gave one single pattern and a D value of 100%. AscI PFGE had a high discriminatory power and a high degree of consistency with epidemiological data and other molecular typing methods for L. pneumophila subtyping, and hence, AscI could be used as a restriction enzyme in PFGE subtyping of L. pneumophila.
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Furugen M, Koide M, Teruya H, Naha Y, Tamayose M, Akamine M, Uchihara T, Atsumi E, Haranaga S, Yara S, Higa F, Tateyama M, Fujita J, Baba M, Sato Y. Legionella pneumonia caused by Legionella pneumophila serogroup 2: second case report in Japan. J Infect Chemother 2008; 14:161-5. [DOI: 10.1007/s10156-008-0594-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2007] [Accepted: 01/30/2008] [Indexed: 11/28/2022]
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