Dataset Information

Large community-acquired Legionnaires' disease outbreak caused by Legionella pneumophila serogroup 1, Italy, July to August 2018.

ABSTRACT: In July 2018, a large outbreak of Legionnaires' disease (LD) caused by Legionella pneumophila serogroup 1 (Lp1) occurred in Bresso, Italy. Fifty-two cases were diagnosed, including five deaths. We performed an epidemiological investigation and prepared a map of the places cases visited during the incubation period. All sites identified as potential sources were investigated and sampled. Association between heavy rainfall and LD cases was evaluated in a case-crossover study. We also performed a case-control study and an aerosol dispersion investigation model. Lp1 was isolated from 22 of 598 analysed water samples; four clinical isolates were typed using monoclonal antibodies and sequence-based typing. Four Lp1 human strains were ST23, of which two were Philadelphia and two were France-Allentown subgroup. Lp1 ST23 France-Allentown was isolated only from a public fountain. In the case-crossover study, extreme precipitation 5-6 days before symptom onset was associated with increased LD risk. The aerosol dispersion model showed that the fountain matched the case distribution best. The case-control study demonstrated a significant eightfold increase in risk for cases residing near the public fountain. The three studies and the matching of clinical and environmental Lp1 strains identified the fountain as the source responsible for the epidemic.

SUBMITTER: Faccini M

PROVIDER: S-EPMC7262491 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Large community-acquired Legionnaires' disease outbreak caused by <i>Legionella pneumophila</i> serogroup 1, Italy, July to August 2018.

Faccini Marino M Russo Antonio Giampiero AG Bonini Maira M Tunesi Sara S Murtas Rossella R Sandrini Monica M Senatore Sabrina S Lamberti Anna A Ciconali Giorgio G Cammarata Serafina S Barrese Eros E Ceriotti Valentina V Vitaliti Sonia S Foti Marina M Gentili Gabriella G Graziano Elisabetta E Panciroli Emerico E Bosio Marco M Gramegna Maria M Cereda Danilo D Perno Carlo Federico CF Mazzola Ester E Campisi Daniela D Aulicino Gianuario G Castaldi Silvana S Girolamo Antonietta A Caporali Maria Grazia MG Scaturro Maria M Rota Maria Cristina MC Ricci Maria Luisa ML

Euro surveillance : bulletin Europeen sur les maladies transmissibles = European communicable disease bulletin 20200501 20

In July 2018, a large outbreak of Legionnaires' disease (LD) caused by <i>Legionella pneumophila</i> serogroup 1 (Lp1) occurred in Bresso, Italy. Fifty-two cases were diagnosed, including five deaths. We performed an epidemiological investigation and prepared a map of the places cases visited during the incubation period. All sites identified as potential sources were investigated and sampled. Association between heavy rainfall and LD cases was evaluated in a case-crossover study. We also perfor ...[more]

PMID: 32458793

Similar Datasets

Project description:UnlabelledA total of 30 Legionella pneumophila serogroup 1 isolates representing 10 separate legionellosis laboratory investigations ("outbreaks") that occurred in New York State between 2004 and 2012 were selected for evaluation of whole-genome sequencing (WGS) approaches for molecular subtyping of this organism. Clinical and environmental isolates were available for each outbreak and were initially examined by pulsed-field gel electrophoresis (PFGE). Sequence-based typing alleles were extracted from WGS data yielding complete sequence types (ST) for isolates representing 8 out of the 10 outbreaks evaluated in this study. Isolates from separate outbreaks sharing the same ST also contained the fewest differences in core genome single nucleotide polymorphisms (SNPs) and the greatest proportion of identical allele sequences in a whole-genome multilocus sequence typing (wgMLST) scheme. Both core SNP and wgMLST analyses distinguished isolates from separate outbreaks, including those from two outbreaks sharing indistinguishable PFGE profiles. Isolates from a hospital-associated outbreak spanning multiple years shared indistinguishable PFGE profiles but displayed differences in their genome sequences, suggesting the presence of multiple environmental sources. Finally, the rtx gene demonstrated differences in the repeat region sequence among ST1 isolates from different outbreaks, suggesting that variation in this gene may be useful for targeted molecular subtyping approaches for L. pneumophila This study demonstrates the utility of various genome sequence analysis approaches for L. pneumophila for environmental source attribution studies while furthering the understanding of Legionella ecology.ImportanceWe demonstrate that whole-genome sequencing helps to improve resolution of Legionella pneumophila isolated during laboratory investigations of legionellosis compared to traditional subtyping methods. These data can be important in confirming the environmental sources of legionellosis outbreaks. Moreover, we evaluated various methods to analyze genome sequence data to help resolve outbreak-related isolates.

Dataset Information

Large community-acquired Legionnaires' disease outbreak caused by Legionella pneumophila serogroup 1, Italy, July to August 2018.

Publications

Large community-acquired Legionnaires' disease outbreak caused by <i>Legionella pneumophila</i> serogroup 1, Italy, July to August 2018.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure