An outbreak of foodborne norovirus gastroenteritis linked to a restaurant in Melbourne, Australia, 2014

Authors

  • Shaun Peter Coutts Victorian Department of Health and Human Services, Melbourne, Australia
  • Kaye Sturge Victorian Department of Health and Human Services, Melbourne, Australia
  • Karin Lalor Victorian Department of Health and Human Services, Melbourne, Australia
  • John Marshall Victorian Infectious Diseases Reference Laboratory, Melbourne, Australia
  • Leesa Bruggink Victorian Infectious Diseases Reference Laboratory, Melbourne, Australia
  • Nela Subasinghe Microbiological Diagnostic Unit Public Health Laboratory, Melbourne, Australia
  • Marion Easton Victorian Department of Health and Human Services, Melbourne, Australia

DOI:

https://doi.org/10.5365/wpsar.2017.8.1.008

Abstract

Introduction: In May 2014 an outbreak of norovirus occurred among patrons of a restaurant in Melbourne, Australia. Investigations were conducted to identify the infectious agent, mode of transmission and source of illness, and to implement controls to prevent further transmission.

Methods: A retrospective case-control study was conducted to test the hypothesis that food served at the restaurant between 9 and 15 May 2014 was the vehicle for infection. A structured questionnaire was used to collect demographic, illness and food exposure data from study participants. To ascertain whether any food handlers had experienced gastroenteritis symptoms and were a possible source of infection, investigators contacted and interviewed staff who had worked at the restaurant between 9 and 16 May 2014.

Results: Forty-six cases (including 16 laboratory-confirmed cases of norovirus) and 49 controls were interviewed and enrolled in the study. Results of the analysis revealed a statistically significant association with illness and consumption of grain salad (OR: 21.6, 95% CI: 1.8–252.7, P = 0.015) and beetroot dip (OR: 22.4, 95% CI: 1.9–267.0, P = 0.014). An interviewed staff member who reported an onset of acute gastrointestinal illness on 12 May 2014 had prepared salads on the day of onset and the previous two days.

Discussion: The outbreak was likely caused by person-to-food-to-person transmission. The outbreak emphasizes the importance of the exclusion of symptomatic food handlers and strict hand hygiene practices in the food service industry to prevent contamination of ready-to-eat foods and the kitchen environment.

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Published

05-05-2017

How to Cite

1.
Coutts SP, Sturge K, Lalor K, Marshall J, Bruggink L, Subasinghe N, Easton M. An outbreak of foodborne norovirus gastroenteritis linked to a restaurant in Melbourne, Australia, 2014. Western Pac Surveill Response J [Internet]. 2017 May 5 [cited 2024 Nov. 21];8(2). Available from: https://ojs.wpro.who.int/ojs/index.php/wpsar/article/view/536

Issue

Section

Outbreak Investigation Report