{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,26]],"date-time":"2026-03-26T04:45:31Z","timestamp":1774500331592,"version":"3.50.1"},"reference-count":37,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2017,6,8]],"date-time":"2017-06-08T00:00:00Z","timestamp":1496880000000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2017,6,8]],"date-time":"2017-06-08T00:00:00Z","timestamp":1496880000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Sci Rep"],"abstract":"<jats:title>Abstract<\/jats:title><jats:p>Legionnaires\u2019 disease, predominantly caused by the bacterium <jats:italic>Legionella pneumophila<\/jats:italic>, has increased in prevalence worldwide. The most common mode of transmission of <jats:italic>Legionella<\/jats:italic> is inhalation of contaminated aerosols, such as those generated by cooling towers. Simple, rapid and accurate methods to enumerate <jats:italic>L. pneumophila<\/jats:italic> are required to prevent the spread of this organism. Here, we applied a microfluidic device for on-chip fluorescent staining and semi-automated counting of <jats:italic>L. pneumophila<\/jats:italic> in cooling tower water. We also constructed a portable system for rapid on-site monitoring and used it to enumerate target bacterial cells rapidly flowing in the microchannel. A fluorescently-labelled polyclonal antibody was used for the selective detection of <jats:italic>L. pneumophila<\/jats:italic> serogroup 1 in the samples. The counts of <jats:italic>L. pneumophila<\/jats:italic> in cooling tower water obtained using the system and fluorescence microscopy were similar. The detection limit of the system was 10<jats:sup>4<\/jats:sup>\u2009cells\/ml, but lower numbers of <jats:italic>L. pneumophila<\/jats:italic> cells (10<jats:sup>1<\/jats:sup> to 10<jats:sup>3<\/jats:sup>\u2009cells\/ml) could be detected following concentration of 0.5\u20133\u2009L of the water sample by filtration. Our technique is rapid to perform (1.5\u2009h), semi-automated (on-chip staining and counting), and portable for on-site measurement, and it may therefore be effective in the initial screening of <jats:italic>Legionella<\/jats:italic> contamination in freshwater.<\/jats:p>","DOI":"10.1038\/s41598-017-03293-9","type":"journal-article","created":{"date-parts":[[2017,6,2]],"date-time":"2017-06-02T13:41:39Z","timestamp":1496410899000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":36,"title":["Rapid on-site monitoring of Legionella pneumophila in cooling tower water using a portable microfluidic system"],"prefix":"10.1038","volume":"7","author":[{"given":"Nobuyasu","family":"Yamaguchi","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yusuke","family":"Tokunaga","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Satoko","family":"Goto","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yudai","family":"Fujii","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fumiya","family":"Banno","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Akiko","family":"Edagawa","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"297","published-online":{"date-parts":[[2017,6,8]]},"reference":[{"key":"3293_CR1","doi-asserted-by":"publisher","first-page":"2417","DOI":"10.1001\/archinte.1994.00420210049006","volume":"154","author":"BJ Marston","year":"1994","unstructured":"Marston, B. J., Lipman, H. B. & Breiman, R. F. Surveillance for Legionnaires\u2019 disease. Risk factors for morbidity and mortality. Arch Intern Med \n                           154, 2417\u20132422, doi:10.1001\/archinte.1994.00420210049006 (1994).","journal-title":"Arch Intern Med"},{"key":"3293_CR2","unstructured":"Meguro, K. Guideline for Prevention of Legionnaires\u2019 Disease - Third Version. (Building Management Education Center, 2009)."},{"key":"3293_CR3","doi-asserted-by":"publisher","first-page":"2540","DOI":"10.1128\/AEM.69.5.2540-2547.2003","volume":"69","author":"A Ohno","year":"2003","unstructured":"Ohno, A., Kato, N., Yamada, K. & Yamaguchi, K. Factors influencing survival of Legionella pneumophila serotype 1 in hot spring water and tap water. Appl Environ Microbiol \n                           69, 2540\u20132547, doi:10.1128\/AEM.69.5.2540-2547.2003 (2003).","journal-title":"Appl Environ Microbiol"},{"key":"3293_CR4","doi-asserted-by":"publisher","first-page":"365","DOI":"10.11150\/kansenshogakuzasshi1970.79.365","volume":"79","author":"M Okada","year":"2005","unstructured":"Okada, M. et al. The largest outbreak of legionellosis in Japan associated with spa baths: epidemic curve and environmental investigation. Kansenshogaku Zasshi \n                           79, 365\u2013374, doi:10.11150\/kansenshogakuzasshi1970.79.365 (2005).","journal-title":"Kansenshogaku Zasshi"},{"key":"3293_CR5","doi-asserted-by":"publisher","first-page":"117","DOI":"10.1007\/s10156-008-0592-5","volume":"14","author":"T Sasaki","year":"2008","unstructured":"Sasaki, T. et al. An outbreak of Legionnaires\u2019 disease associated with a circulating bathwater system at a public bathhouse. I: a clinical analysis. J Infect Chemother \n                           14, 117\u2013112, doi:10.1007\/s10156-008-0592-5 (2008).","journal-title":"J Infect Chemother"},{"key":"3293_CR6","doi-asserted-by":"publisher","first-page":"203","DOI":"10.1111\/1348-0421.12366","volume":"60","author":"N Ishizaki","year":"2016","unstructured":"Ishizaki, N. et al. Legionella thermalis sp. nov., isolated from hot spring water in Tokyo, Japan. Microbiol Immunol \n                           60, 203\u2013208, doi:10.1111\/1348-0421.12366 (2016).","journal-title":"Microbiol Immunol"},{"key":"3293_CR7","doi-asserted-by":"publisher","first-page":"127","DOI":"10.1086\/341087","volume":"186","author":"VL Yu","year":"2002","unstructured":"Yu, V. L. et al. Distribution of Legionella species and serogroups isolated by culture in patients with sporadic community-acquired legionellosis: an international collaborative survey. J Infect Dis \n                           186, 127\u2013128, doi:10.1086\/341087 (2002).","journal-title":"J Infect Dis"},{"key":"3293_CR8","doi-asserted-by":"publisher","first-page":"2104","DOI":"10.1111\/j.1365-2672.2008.03932.x","volume":"105","author":"A Edagawa","year":"2008","unstructured":"Edagawa, A. et al. Detection of culturable and nonculturable Legionella species from hot water systems of public buildings in Japan. J Appl Microbiol \n                           105, 2104\u20132114, doi:10.1111\/j.1365-2672.2008.03932.x (2008).","journal-title":"J Appl Microbiol"},{"key":"3293_CR9","doi-asserted-by":"crossref","first-page":"2047","DOI":"10.1128\/aem.63.5.2047-2053.1997","volume":"63","author":"M Steinert","year":"1997","unstructured":"Steinert, M., Em\u00f6dy, L., Amann, R. & Hacker, J. Resuscitation of viable but nonculturable Legionella pneumophila Philadelphia JR32 by Acanthamoeba castellanii. 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Int J Environ Res Public Health \n                           12, 13118\u201313130, doi:10.3390\/ijerph121013118 (2015).","journal-title":"Int J Environ Res Public Health"},{"key":"3293_CR12","doi-asserted-by":"publisher","first-page":"264","DOI":"10.1002\/cyto.a.20858","volume":"77A","author":"HP F\u00fcchslin","year":"2010","unstructured":"F\u00fcchslin, H. P., K\u00f6tzsch, S., Keserue, H. A. & Egli, T. Rapid and quantitative detection of Legionella pneumophila applying immunomagnetic separation and flow cytometry. Cytometry \n                           77A, 264\u2013274, doi:10.1002\/cyto.a.20858 (2010).","journal-title":"Cytometry A"},{"key":"3293_CR13","doi-asserted-by":"publisher","first-page":"753","DOI":"10.1111\/j.1751-7915.2012.00366.x","volume":"5","author":"HA Keserue","year":"2012","unstructured":"Keserue, H. A., Baumgartner, A., Felleisen, R. & Egli, T. 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Rapid enumeration of active Legionella pneumophila in freshwater environments by the microcolony method combined with direct fluorescent antibody staining. Microbes Environ \n                           27, 324\u2013326, doi:10.1264\/jsme2.ME11324 (2012).","journal-title":"Microbes Environ"},{"key":"3293_CR24","doi-asserted-by":"publisher","first-page":"643","DOI":"10.1016\/j.mimet.2006.11.003","volume":"68","author":"C Sakamoto","year":"2007","unstructured":"Sakamoto, C. et al. Rapid quantification of bacterial cells in potable water using a simplified microfluidic device. J Microbiol Methods \n                           68, 643\u2013647, doi:10.1016\/j.mimet.2006.11.003 (2007).","journal-title":"J Microbiol Methods"},{"key":"3293_CR25","doi-asserted-by":"publisher","first-page":"2978","DOI":"10.1039\/C4LC00394B","volume":"14","author":"G Comina","year":"2014","unstructured":"Comina, G., Suska, A. & Filippini, D. Low cost lab-on-a-chip prototyping with a consumer grade 3D printer. 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Four-year bacterial monitoring in the International Space Station \u2013 Japanese Experiment Module \u201cKibo\u201d with culture-independent approach. npj Microgravity \n                           2, Article number 16007, doi:10.1038\/npjmgrav.2016.7\u00a0(2016).","DOI":"10.1038\/npjmgrav.2016.7"},{"key":"3293_CR28","doi-asserted-by":"publisher","unstructured":"Park, J., Ichijo, T., Nasu, M. & Yamaguchi, N. Investigation of bacterial effects of Asian dust events through comparison with seasonal variability in outdoor airborne bacterial community. Sci Rep \n                           6, Article number: 35706, doi:10.1038\/srep35706\u00a0(2016).","DOI":"10.1038\/srep35706"},{"key":"3293_CR29","doi-asserted-by":"publisher","unstructured":"Tokel, O. et al. Portable microfluidic integrated plasmonic platform for pathogen detection. 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On-site monitoring of harmful bacteria in river environments by portable system. Progress Reports of the River Foundation. 26-1215-022. http:\/\/public-report.kasen.or.jp\/261215022.pdf."},{"key":"3293_CR35","doi-asserted-by":"publisher","first-page":"699","DOI":"10.1128\/AEM.68.2.699-704.2002","volume":"68","author":"M Kawai","year":"2002","unstructured":"Kawai, M. et al. 16S ribosomal DNA-based analysis of bacterial diversity in purified water used in pharmaceutical manufacturing processes by PCR and denaturing gradient gel electrophoresis. Appl Environ Microbiol \n                           68, 699\u2013704, doi:10.1128\/AEM.68.2.699-704.2002 (2002).","journal-title":"Appl Environ Microbiol"},{"key":"3293_CR36","doi-asserted-by":"publisher","first-page":"163","DOI":"10.1264\/jsme2.ME09120","volume":"24","author":"T Baba","year":"2009","unstructured":"Baba, T., Yamaguchi, N., Matsumoto, R. & Nasu, M. 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Ecol Res \n                           26, 893\u2013896, doi:10.1007\/s11284-010-0707-1 (2011).","journal-title":"Ecol Res"}],"container-title":["Scientific Reports"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.nature.com\/articles\/s41598-017-03293-9.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/www.nature.com\/articles\/s41598-017-03293-9","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/www.nature.com\/articles\/s41598-017-03293-9.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2022,12,23]],"date-time":"2022-12-23T05:07:57Z","timestamp":1671772077000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.nature.com\/articles\/s41598-017-03293-9"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2017,6,8]]},"references-count":37,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2017,12]]}},"alternative-id":["3293"],"URL":"https:\/\/doi.org\/10.1038\/s41598-017-03293-9","relation":{},"ISSN":["2045-2322"],"issn-type":[{"value":"2045-2322","type":"electronic"}],"subject":[],"published":{"date-parts":[[2017,6,8]]},"assertion":[{"value":"5 December 2016","order":1,"name":"received","label":"Received","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"26 April 2017","order":2,"name":"accepted","label":"Accepted","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"8 June 2017","order":3,"name":"first_online","label":"First Online","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"The authors declare that they have no competing interests.","order":1,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing Interests"}}],"article-number":"3092"}}