{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,21]],"date-time":"2026-04-21T08:59:19Z","timestamp":1776761959941,"version":"3.51.2"},"reference-count":25,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,4,21]],"date-time":"2026-04-21T00:00:00Z","timestamp":1776729600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>Legionnaires\u2019 disease is a rare cause of atypical pneumonia associated with a high mortality rate among untreated patients. In Romania, the disease has historically been underreported due to insufficient surveillance and limited diagnostic capacity. The aim of this study was to describe the characteristics of Legionnaires\u2019 disease cases admitted to a specialized infectious disease hospital between 2023 and 2024, with a particular focus on a cluster associated with travel to a spa resort. Most cases included in our study (31\/36) were confirmed by urinary antigen testing, while one case was confirmed by a significant increase in the level of specific antibodies against Legionella pneumophila serogroup 1 in paired serum samples. The most frequently reported symptom was fever (28\/32), followed by chills (24\/32). Among the 32 confirmed cases, 3 patients died. Two cases were identified as part of a family cluster involving a father and son who had undergone physiotherapy at a balneary resort. Both patients presented with fever and gastrointestinal symptoms, and radiological investigations confirmed mixed pneumonia associated with an intense inflammatory syndrome. In the father\u2019s case, hepatic involvement and interstitial nephritis were also identified. Early diagnosis based on epidemiological data, clinical predictive scores, and laboratory investigations would allow timely administration of targeted antibiotic therapy and may contribute to reduced mortality.<\/jats:p>","DOI":"10.3390\/microorganisms14040935","type":"journal-article","created":{"date-parts":[[2026,4,21]],"date-time":"2026-04-21T07:57:21Z","timestamp":1776758241000},"page":"935","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Characteristics of Legionnaires\u2019 Disease Cases Hospitalized at a Specialized Infectious Disease Hospital, 2023\u20132024, with a Focus on Clusters Associated with Travel to a Spa Resort"],"prefix":"10.3390","volume":"14","author":[{"given":"Constan\u021ba-Angelica","family":"Vi\u0219an","sequence":"first","affiliation":[{"name":"Faculty of Dentistry, Department of Infectious Diseases, \u201cCarol Davila\u201d University of Medicine and Pharmacy, 050474 Bucharest, Romania"},{"name":"National Institute for Infectious Diseases \u201cProf. Dr. Matei Bals\u201d, 021105 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Gina","family":"Filip","sequence":"additional","affiliation":[{"name":"National Institute for Mother and Child Health \u201cAlessandrescu-Rusescu\u201d (NIMCH \u201cAlessandrescu-Rusescu\u201d), 120 Lacul Tei Boulevard, 2nd District, 020395 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-9635-1177","authenticated-orcid":false,"given":"Carmen-Cristina","family":"Vasile","sequence":"additional","affiliation":[{"name":"National Institute for Infectious Diseases \u201cProf. Dr. Matei Bals\u201d, 021105 Bucharest, Romania"},{"name":"Faculty of Medicine, Department of Epidemiology I, \u201cCarol Davila\u201d University of Medicine and Pharmacy, 021105 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Anca Cristina","family":"Dr\u0103g\u0103nescu","sequence":"additional","affiliation":[{"name":"National Institute for Infectious Diseases \u201cProf. Dr. Matei Bals\u201d, 021105 Bucharest, Romania"},{"name":"Faculty of Medicine, Department of Pediatrics, \u201cCarol Davila\u201d University of Medicine and Pharmacy, 050474 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4193-063X","authenticated-orcid":false,"given":"Gheorghi\u021b\u0103","family":"Jugulete","sequence":"additional","affiliation":[{"name":"Faculty of Dentistry, Department of Infectious Diseases, \u201cCarol Davila\u201d University of Medicine and Pharmacy, 050474 Bucharest, Romania"},{"name":"National Institute for Infectious Diseases \u201cProf. Dr. Matei Bals\u201d, 021105 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Anca","family":"Streinu-Cercel","sequence":"additional","affiliation":[{"name":"National Institute for Infectious Diseases \u201cProf. Dr. Matei Bals\u201d, 021105 Bucharest, Romania"},{"name":"Faculty of Medicine, Department of Infectious Disease, \u201cCarol Davila\u201d University of Medicine and Pharmacy, 050474 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Andreea","family":"Tudor","sequence":"additional","affiliation":[{"name":"National Institute for Infectious Diseases \u201cProf. Dr. Matei Bals\u201d, 021105 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lauren\u021biu Mih\u0103i\u021b\u0103","family":"Stratan","sequence":"additional","affiliation":[{"name":"National Institute for Infectious Diseases \u201cProf. Dr. Matei Bals\u201d, 021105 Bucharest, Romania"},{"name":"Faculty of Medicine, Department of Infectious Disease, \u201cCarol Davila\u201d University of Medicine and Pharmacy, 050474 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4118-8268","authenticated-orcid":false,"given":"Daniela","family":"Pi\u021bigoi","sequence":"additional","affiliation":[{"name":"National Institute for Infectious Diseases \u201cProf. Dr. Matei Bals\u201d, 021105 Bucharest, Romania"},{"name":"Faculty of Medicine, Department of Epidemiology I, \u201cCarol Davila\u201d University of Medicine and Pharmacy, 021105 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6514-0122","authenticated-orcid":false,"given":"Ana Maria","family":"Tudor","sequence":"additional","affiliation":[{"name":"Faculty of Dentistry, Department of Infectious Diseases, \u201cCarol Davila\u201d University of Medicine and Pharmacy, 050474 Bucharest, Romania"},{"name":"National Institute for Infectious Diseases \u201cProf. Dr. Matei Bals\u201d, 021105 Bucharest, 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Med."}],"container-title":["Microorganisms"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2076-2607\/14\/4\/935\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,4,21]],"date-time":"2026-04-21T08:16:37Z","timestamp":1776759397000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2076-2607\/14\/4\/935"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,4,21]]},"references-count":25,"journal-issue":{"issue":"4","published-online":{"date-parts":[[2026,4]]}},"alternative-id":["microorganisms14040935"],"URL":"https:\/\/doi.org\/10.3390\/microorganisms14040935","relation":{},"ISSN":["2076-2607"],"issn-type":[{"value":"2076-2607","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,4,21]]}}}