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An outbreak of norovirus GI-6 infection following a wedding in North West England

  • K. C. SMITH (a1) (a2), T. INNS (a3) (a4), V. DECRAENE (a3), A. FOX (a5), D. J. ALLEN (a4) (a6) and A. SHAH (a1)...

In August 2015 a gastroenteritis outbreak occurred following a wedding. An outbreak investigation was undertaken and a cohort study was conducted using an online survey. Of 140 guests, 134 received the survey and 113 responded (84·3% response rate). Seventy respondents met the case definition of vomiting and/or diarrhoea within 72 h of the wedding (61·9% attack rate). Fifteen exposures were associated with illness; on stratification, all were confounded by the ham hock starter. Multivariable analysis showed a significant association with exposure to ham hock (risk ratio 6·62, 95% confidence interval 2·19–20·03). Eight guests and two catering staff submitted stool samples. All tested positive for norovirus GI-6 infection, including a food handler who had vomiting less than 48 h before the wedding. A single genotype was detected among all samples, suggesting a single source of contamination. The transmission pattern suggested point-source exposure. The most plausible cause of the outbreak was transmission from an infected food handler via contaminated food. This highlights the importance of appropriate exclusions for symptomatic food handlers. Additionally, the food handler's stool sample was submitted 7 days after symptom resolution. The potential for extended viral excretion, and the extremely low infective dose of norovirus, may mean that current exclusion guidelines are not of sufficient duration.

Corresponding author
*Author for correspondence: Dr A. Shah, Health Protection Team, Public Health England, North West, UK. (Email:
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1. Norovirus Working Group. Guidance for the management of norovirus infection in cruise ships. London: Health Protection Agency, 2007.
2. Tam CC, et al. Longitudinal study of infectious intestinal disease in the UK (IID2 study): incidence in the community and presenting to general practice. Gut 2012; 61: 6977.
3. Tam CC, O'Brien SJ. Economic cost of campylobacter, norovirus and rotavirus disease in the United Kingdom. PLoS ONE. Published online: 1 February 2016. doi:10.1371/journal.pone.0138526.
4. Hawker J, et al. Communicable Disease Control and Health Protection Handbook, 3rd edn. Chichester: Wiley-Blackwell, 2012.
5. Barrabeig I, et al. Foodborne norovirus outbreak: the role of an asymptomatic food handler. BMC Infectious Diseases. Published online: 15 September 2010.doi:10.1186/1471-2334-10-269.
6. Franck KT, et al. Sources of calicivirus contamination in foodborne outbreaks in Denmark, 2005–2011 – the role of the asymptomatic food handler. Journal of Infectious Diseases 2015; 211: 563570.
7. Patterson T, Hutchings P, Palmer S. Outbreak of SRSV gastroenteritis at an international conference traced to food handled by a post-symptomatic caterer. Epidemiology and Infection 1993; 111: 157162.
8. Thornley CN, et al. Multiple outbreaks of a novel norovirus GII.4 linked to an infected post-symptomatic food handler. Epidemiology and Infection 2013; 141: 15851597.
9. Einöder-Moreno M, et al. Non-heat-treated frozen raspberries the most likely vehicle of a norovirus outbreak in Oslo, Norway, November 2013. Epidemiology and Infection. Published online: 16 February 2016. doi:10.1017/S0950268816000194.
10. Boom R, et al. Rapid and simple method for purification of nucleic acids. Journal of Clinical Microbiology 1990; 28: 495503.
11. Kageyama T, et al. Broadly reactive and highly sensitive assay for Norwalk-like viruses based on real-time quantitative reverse transcription-PCR. Journal of Clinical Microbiology 2003; 41: 14581557.
12. Kojima S, et al. Genogroup-specific PCR primers for detection of Norwalk-like viruses. Journal of Virological Methods 2002; 100: 107114.
13. Gallimore CI, et al. Diversity of noroviruses cocirculating in the North of England from 1998 to 2001. Journal of Clinical Microbiology 2004; 42: 13961401.
14. Maunula L, Miettinen IT, von Bonsdorff CH. Norovirus outbreaks from drinking water. Emerging Infectious Diseases 2005; 11: 17161721.
15. Xerry J, et al. Genetic characterization of genogroup I norovirus in outbreaks of gastroenteritis. Journal of Clinical Microbiology 2010; 48: 25602562.
16. Bruggink LD, Dunbar NL, Marshall JA. Norovirus genotype diversity in community-based sporadic gastroenteritis incidents: a five-year study. Journal of Medical Virology 2015; 87: 961969.
17. Leshem E, et al. Genotype GI.6 norovirus, United States, 2010–2012. Emerging Infectious Diseases 2013; 19: 13171320.
18. Rockx B, et al. Natural history of human calicivirus infection: a prospective cohort study. Clinical Infectious Diseases 2002; 35: 246253.
19. Atmar RL, et al. Norwalk virus shedding after experimental human infection. Emerging Infectious Diseases 2008; 15: 15531557.
20. Tamura K, et al. MEGA6: Molecular Evolutionary Genetics Analysis version 6.0. Molecular Biology and Evolution 2013; 30: 27252729.
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Epidemiology & Infection
  • ISSN: 0950-2688
  • EISSN: 1469-4409
  • URL: /core/journals/epidemiology-and-infection
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