Phylogenetic structure of European Salmonella Enteritidis outbreak correlates with national and international egg distribution network

Research output: Contribution to journalArticle

Authors

  • Tim Dallman
  • Thomas Inns
  • Thibaut Jombart
  • Philip Ashton
  • Carol Chatt
  • Ute Messelhaeusser
  • Wolfgang Rabsch
  • Sandra Simon
  • Sergejs Nikisins
  • Helen Bernard
  • Simon le Hello
  • Nathalie Jourdan da-Silva
  • Christian Kornschober
  • Joel Mossong
  • Elizabeth de Pinna
  • Kathie Grant
  • Paul Cleary

Colleges, School and Institutes

External organisations

  • Public Health England
  • Imperial College London
  • Institute of Microbiology and Infection, University of Birmingham, Birmingham, B15 2TT, UK. n.j.loman@bham.ac.uk.
  • Bavarian Health and Food Safety Authority, Oberschleissheim, Germany.
  • Robert Koch Institute, Division for Enteropathogenic Bacteria and Legionella, Wernigerode , Germany.
  • Department for Infectious Disease Epidemiology at the Robert Koch Institute, Berlin , Germany.
  • Institut Pasteur, Centre national de reference des E. coli, Shigella et Salmonella , Paris , France.
  • French Institute for Public Health Surveillance , France.
  • Austrian Agency for Health and Food Safety, National Reference Centre for Salmonella , Graz , Austria.
  • Surveillance & epidemiology of infectious diseases, Laboratoire National de Santé, Dudelange, Luxembourg.

Abstract

Outbreaks of Salmonella Enteritidis have long been associated with contaminated poultry and eggs. In the summer of 2014 a large multi-national outbreak of Salmonella Enteritidis phage type 14b occurred with over 350 cases reported in the United Kingdom, Germany, Austria, France and Luxembourg. Egg supply network investigation and microbiological sampling identified the source to be a Bavarian egg producer. As part of the international investigation into the outbreak, over 400 isolates were sequenced including isolates from cases, implicated UK premises and eggs from the suspected source producer. We were able to show a clear statistical correlation between the topology of the UK egg distribution network and the phylogenetic network of outbreak isolates. This correlation can most plausibly be explained by different parts of the egg distribution network being supplied by eggs solely from independent premises of the Bavarian egg producer (Company X). Microbiological sampling from the source premises, traceback information and information on the interventions carried out at the egg production premises all supported this conclusion. The level of insight into the outbreak epidemiology provided by whole-genome sequencing (WGS) would not have been possible using traditional microbial typing methods.

Details

Original languageEnglish
Article numbere000070
JournalMicrobial Genomics
Volume2
Issue number8
Publication statusPublished - 25 Aug 2016

Keywords

  • Journal Article