title: Genomic Investigation of a Legionellosis Outbreak in a Persistently Colonized Hotel.
abstract: OBJECTIVE
  A long-lasting legionellosis outbreak was reported between November 2011 and July 2012 in a hotel in Calpe (Spain) affecting 44 patients including six deaths. Intensive epidemiological and microbiological investigations were performed in order to detect the reservoirs.
  
  
  METHODS
  Clinical and environmental samples were tested for the presence and genetic characterization of Legionella pneumophila. Six of the isolates were subjected to whole-genome sequencing.
  
  
  RESULTS
  Sequencing of 14 clinical and 260 environmental samples revealed sequence type (ST) 23 as the main responsible strain for the infections. This ST was found in the spa pool, from where it spread to other hotel public spaces, explaining the ST23 clinical cases, including guests who had not visited the spa. Uncultured clinical specimens showed profiles compatible with ST23, ST578, and mixed patterns. Profiles compatible with ST578 were obtained by direct sequencing from biofilm samples collected from the domestic water system, which provided evidence for the source of infection for non ST23 patients. Whole genome data from five ST23 strains and the identification of different STs and Legionella species showed that different hotel premises were likely colonized since the hotel opening thus explaining how different patients had been infected by distinct STs.
  
  
  CONCLUSIONS
  Both epidemiological and molecular data are essential in the investigation of legionellosis outbreaks. Whole-genome sequencing data revealed significant intra-ST variability and allowed to make further inference on the short-term evolution of a local colonization of L. pneumophila.
authors.affiliation: Unidad Mixta "Infección y Salud Pública" Fundación para el Fomento de la Investigación Sanitaria y Biomédica de la Comunitat Valenciana-Salud Pública, Universitat de ValènciaValencia, Spain; Centros de Investigación Biomédica en Red Epidemiología y Salud PúblicaValencia, Spain.
authors.forename: Leonor
authors.initials: L
authors.lastname: Sánchez-Busó
authors.affiliation: Unidad Mixta "Infección y Salud Pública" Fundación para el Fomento de la Investigación Sanitaria y Biomédica de la Comunitat Valenciana-Salud Pública, Universitat de ValènciaValencia, Spain; Dirección General de Salud Pública, Subdirección de Epidemiología y Vigilancia de la SaludValencia, Spain.
authors.forename: Silvia
authors.initials: S
authors.lastname: Guiral
authors.affiliation: Biolinea IntPalma de Mallorca, Spain; Policlínica MiramarPalma de Mallorca, Spain.
authors.forename: Sebastián
authors.initials: S
authors.lastname: Crespi
authors.affiliation: Legioprev Valencia, Spain.
authors.forename: Víctor
authors.initials: V
authors.lastname: Moya
authors.affiliation: Dirección General de Salud Pública, Laboratorio de Salud Pública Valencia, Spain.
authors.forename: María L
authors.initials: ML
authors.lastname: Camaró
authors.affiliation: Dirección General de Salud Pública, Laboratorio de Salud Pública Valencia, Spain.
authors.forename: María P
authors.initials: MP
authors.lastname: Olmos
authors.affiliation: Legioprev Valencia, Spain.
authors.forename: Francisco
authors.initials: F
authors.lastname: Adrián
authors.affiliation: Centro de Salud Pública Denia Denia, Spain.
authors.forename: Vicente
authors.initials: V
authors.lastname: Morera
authors.affiliation: Unidad Mixta "Infección y Salud Pública" Fundación para el Fomento de la Investigación Sanitaria y Biomédica de la Comunitat Valenciana-Salud Pública, Universitat de ValènciaValencia, Spain; Dirección General de Salud Pública, Subdirección de Epidemiología y Vigilancia de la SaludValencia, Spain.
authors.forename: Francisco
authors.initials: F
authors.lastname: González-Morán
authors.affiliation: Unidad Mixta "Infección y Salud Pública" Fundación para el Fomento de la Investigación Sanitaria y Biomédica de la Comunitat Valenciana-Salud Pública, Universitat de ValènciaValencia, Spain; Dirección General de Salud Pública, Subdirección de Epidemiología y Vigilancia de la SaludValencia, Spain.
authors.forename: Hermelinda
authors.initials: H
authors.lastname: Vanaclocha
authors.affiliation: Unidad Mixta "Infección y Salud Pública" Fundación para el Fomento de la Investigación Sanitaria y Biomédica de la Comunitat Valenciana-Salud Pública, Universitat de ValènciaValencia, Spain; Centros de Investigación Biomédica en Red Epidemiología y Salud PúblicaValencia, Spain.
authors.forename: Fernando
authors.initials: F
authors.lastname: González-Candelas
keywords: Legionnaire's disease (LD); complete genome; mixed infections; outbreaks; typing
references.citation: Bioinformatics. 2006 Nov 1;22(21):2688-90
references.pmid: 16928733
references.citation: Clin Infect Dis. 2013 Jul;57(1):48-56
references.pmid: 23511302
references.citation: Infect Genet Evol. 2015 Mar;30:45-54
references.pmid: 25511251
references.citation: Clin Microbiol Infect. 2014 Jan;20(1):O13-9
references.pmid: 23910438
references.citation: Infection. 2004 Aug;32(4):242-5
references.pmid: 15293082
references.citation: Genome Biol. 2014;15(11):504
references.pmid: 25370747
references.citation: BMC Genomics. 2010 Mar 17;11:181
references.pmid: 20236513
references.citation: Int J Med Microbiol. 2007 Nov;297(7-8):577-87
references.pmid: 17467337
references.citation: Euro Surveill. 2012 Feb 23;17(8):null
references.pmid: 22401506
references.citation: Nat Genet. 2004 Nov;36(11):1165-73
references.pmid: 15467720
references.citation: Nat Genet. 2014 Nov;46(11):1205-11
references.pmid: 25282102
references.citation: Am J Epidemiol. 1978 Feb;107(2):149-60
references.pmid: 623097
references.citation: Science. 2010 Jan 22;327(5964):469-74
references.pmid: 20093474
references.citation: Nat Genet. 2014 Mar;46(3):305-9
references.pmid: 24509479
references.citation: Mol Biol Evol. 2011 Oct;28(10):2731-9
references.pmid: 21546353
references.citation: Euro Surveill. 2011 Oct 06;16(40):null
references.pmid: 21996379
references.citation: Ann Intern Med. 1980 Aug;93(2):240-3
references.pmid: 6996551
references.citation: J Clin Microbiol. 2009 Sep;47(9):2901-5
references.pmid: 19605573
references.citation: Lancet. 2013 May 4;381(9877):1551-60
references.pmid: 23541540
references.citation: Nucleic Acids Res. 1991 Jul 25;19(14):4008
references.pmid: 1861999
references.citation: Int J Med Microbiol. 2014 May;304(3-4):307-13
references.pmid: 24309206
references.citation: Mol Biol Evol. 2012 Aug;29(8):1969-73
references.pmid: 22367748
references.citation: J Med Microbiol. 2010 Oct;59(Pt 10):1242-6
references.pmid: 20558588
references.citation: N Engl J Med. 1977 Dec 1;297(22):1189-97
references.pmid: 335244
references.citation: Environ Microbiol. 2007 Mar;9(3):643-56
references.pmid: 17298365
references.citation: Eur J Clin Microbiol Infect Dis. 2012 Aug;31(8):2017-28
references.pmid: 22278293
references.citation: J Clin Microbiol. 1983 Nov;18(5):1040-6
references.pmid: 6358248
references.citation: BMJ Open. 2013 Jan 09;3(1):null
references.pmid: 23306006
references.citation: J Clin Microbiol. 2011 Dec;49(12):4052-8
references.pmid: 21956982
references.citation: Science. 2004 Sep 24;305(5692):1966-8
references.pmid: 15448271
references.citation: J Infect Dis. 2002 Jan 15;185(2):237-43
references.pmid: 11807698
references.citation: J Chromatogr B Analyt Technol Biomed Life Sci. 2005 Jun 5;820(1):137-41
references.pmid: 15866502
references.citation: BMC Genomics. 2011 Nov 01;12:536
references.pmid: 22044686
references.citation: J Clin Microbiol. 2005 May;43(5):2047-52
references.pmid: 15872220
references.citation: J Clin Microbiol. 2009 Apr;47(4):981-7
references.pmid: 19225096
references.citation: J Clin Microbiol. 1986 Apr;23(4):768-71
references.pmid: 3517064
references.citation: PLoS One. 2014 Aug 08;9(8):e103852
references.pmid: 25105285
references.citation: J Clin Microbiol. 2003 Jul;41(7):2932-9
references.pmid: 12843023
references.citation: Am J Med. 1983 Apr;74(4):609-14
references.pmid: 6837589
references.citation: Curr Protoc Bioinformatics. 2010 Sep;Chapter 11:Unit 11.5
references.pmid: 20836074
references.citation: J Bacteriol. 2010 Nov;192(22):6001-16
references.pmid: 20833813
references.citation: Mol Biol Evol. 1993 Sep;10(5):1073-95
references.pmid: 8412650
references.citation: Clin Infect Dis. 2007 Jan 15;44(2):222-8
references.pmid: 17173221