Dataset Information

Retrospective use of whole genome sequencing to better understand an outbreak of Salmonella enterica serovar Mbandaka in New South Wales, Australia.

ABSTRACT:

Introduction

Salmonella enterica serovar Mbandaka is an infrequent cause of salmonellosis in New South Wales (NSW) with an average of 17 cases reported annually. This study examined the added value of whole genome sequencing (WGS) for investigating a non-point source outbreak of Salmonella ser. Mbandaka with limited geographical spread.

Methods

In February 2016, an increase in Salmonella ser. Mbandaka was noted in New South Wales, and an investigation was initiated. A WGS study was conducted three months after the initial investigation, analysing the outbreak Salmonella ser. Mbandaka isolates along with 17 human and non-human reference strains from 2010 to 2015.

Results

WGS analysis distinguished the original outbreak cases (n = 29) into two main clusters: Cluster A (n = 11) and Cluster B (n = 6); there were also 12 sporadic cases. Reanalysis of food consumption histories of cases by WGS cluster provided additional specificity when assessing associations.

Discussion

WGS has been widely acknowledged as a promising high-resolution typing tool for enteric pathogens. This study was one of the first to apply WGS to a geographically limited cluster of salmonellosis in Australia. WGS clearly distinguished the outbreak cases into distinct clusters, demonstrating its potential value for use in real time to support non-point source foodborne disease outbreaks of limited geographical spread.

SUBMITTER: Lindsay C

PROVIDER: S-EPMC6059765 | biostudies-literature | 2018 Apr-Jun

REPOSITORIES: biostudies-literature

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Publications

Retrospective use of whole genome sequencing to better understand an outbreak of <i>Salmonella enterica</i> serovar Mbandaka in New South Wales, Australia.

Lindsay Cassia C Flint James J Lilly Kim K Hope Kirsty K Wang Qinning Q Howard Peter P Sintchenko Vitali V Durrheim David N DN

Western Pacific surveillance and response journal : WPSAR 20180423 2

<h4>Introduction</h4><i>Salmonella enterica</i> serovar Mbandaka is an infrequent cause of salmonellosis in New South Wales (NSW) with an average of 17 cases reported annually. This study examined the added value of whole genome sequencing (WGS) for investigating a non-point source outbreak of <i>Salmonella</i> ser. Mbandaka with limited geographical spread.<h4>Methods</h4>In February 2016, an increase in <i>Salmonella</i> ser. Mbandaka was noted in New South Wales, and an investigation was init ...[more]

PMID: 30057854

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