{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,7]],"date-time":"2026-09-07T17:09:41Z","timestamp":1788800981141,"version":"build-2803163510"},"reference-count":38,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,9,5]],"date-time":"2026-09-05T00:00:00Z","timestamp":1788566400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>Legionella pneumophila, the causative agent of Legionnaires\u2019 disease, remains a major public health concern in water systems. Chlorination is the most widely used disinfection strategy but presents important limitations, including reduced stability in hot water systems and the generation of carcinogenic by-products. This study evaluated ozonation as an alternative disinfection method, comparing its efficacy with chlorination against different physiological states of L. pneumophila, including culturable and viable but non-culturable (VBNC) cells, as well as biofilm-associated bacteria and amoebal hosts. The biocidal effect of ozone and chlorination on planktonic L. pneumophila was assessed by culture and viability-qPCR. Biofilm viability was evaluated using fluorescein diacetate staining, whereas amoeba viability was determined by flow cytometry. Ozonation achieved complete inactivation of both culturable and VBNC L. pneumophila within 5 min. In contrast, chlorination achieved complete loss of culturability only at high concentrations and was associated with the persistence of VBNC cells. Neither ozonation nor chlorination significantly reduced established biofilms or amoebae. These findings indicate that ozonation is a promising strategy for rapid inactivation of planktonic L. pneumophila and may overcome important limitations associated with chlorine-based treatments.<\/jats:p>","DOI":"10.3390\/pathogens15090943","type":"journal-article","created":{"date-parts":[[2026,9,7]],"date-time":"2026-09-07T16:30:02Z","timestamp":1788798602000},"page":"943","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Ozonation Eliminates Viable but Not Culturable Legionella pneumophila More Effectively than Chlorination"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7468-6979","authenticated-orcid":false,"given":"Elisenda","family":"Arqu\u00e9","sequence":"first","affiliation":[{"name":"Clinical and Environmental Infectious Diseases Study Group, Germans Trias i Pujol Research Institute, Carretera de Can Ruti, Cam\u00ed de les Escoles s\/n, 08916 Badalona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"methodology","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"given":"Marina","family":"Simon-Coma","sequence":"additional","affiliation":[{"name":"Clinical and Environmental Infectious Diseases Study Group, Germans Trias i Pujol Research Institute, Carretera de Can Ruti, Cam\u00ed de les Escoles s\/n, 08916 Badalona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-3490-4912","authenticated-orcid":false,"given":"Pol","family":"Oliveras","sequence":"additional","affiliation":[{"name":"Clinical and Environmental Infectious Diseases Study Group, Germans Trias i Pujol Research Institute, Carretera de Can Ruti, Cam\u00ed de les Escoles s\/n, 08916 Badalona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"methodology","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"given":"Esteban Alberto","family":"Reynaga","sequence":"additional","affiliation":[{"name":"Clinical and Environmental Infectious Diseases Study Group, Germans Trias i Pujol Research Institute, Carretera de Can Ruti, Cam\u00ed de les Escoles s\/n, 08916 Badalona, Spain"},{"name":"Department of Infectious Diseases, Hospital Universitari Germans Trias i Pujol, Carretera de Can Ruti, 08916 Badalona, Spain"},{"name":"Fundaci\u00f3 Lluita Contra les Infeccions, Infectious Diseases Department, Hospital Universitari Germans Trias i Pujol, 08916 Badalona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"given":"Nieves","family":"Sopena","sequence":"additional","affiliation":[{"name":"Clinical and Environmental Infectious Diseases Study Group, Germans Trias i Pujol Research Institute, Carretera de Can Ruti, Cam\u00ed de les Escoles s\/n, 08916 Badalona, Spain"},{"name":"Department of Infectious Diseases, Hospital Universitari Germans Trias i Pujol, Carretera de Can Ruti, 08916 Badalona, Spain"},{"name":"Fundaci\u00f3 Lluita Contra les Infeccions, Infectious Diseases Department, Hospital Universitari Germans Trias i Pujol, 08916 Badalona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"resources","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"given":"Maria Llu\u00efsa","family":"Pedro-Botet","sequence":"additional","affiliation":[{"name":"Clinical and Environmental Infectious Diseases Study Group, Germans Trias i Pujol Research Institute, Carretera de Can Ruti, Cam\u00ed de les Escoles s\/n, 08916 Badalona, Spain"},{"name":"Department of Infectious Diseases, Hospital Universitari Germans Trias i Pujol, Carretera de Can Ruti, 08916 Badalona, Spain"},{"name":"Fundaci\u00f3 Lluita Contra les Infeccions, Infectious Diseases Department, Hospital Universitari Germans Trias i Pujol, 08916 Badalona, Spain"},{"name":"Department of Medicine, Universitat Aut\u00f2noma de Barcelona, Carretera de Can Ruti, 08916 Badalona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"writing-original-draft","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0376-5036","authenticated-orcid":false,"given":"Noem\u00ed","family":"P\u00e1rraga-Ni\u00f1o","sequence":"additional","affiliation":[{"name":"Clinical and Environmental Infectious Diseases Study Group, Germans Trias i Pujol Research Institute, Carretera de Can Ruti, Cam\u00ed de les Escoles s\/n, 08916 Badalona, 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