a1 Thames Valley HPU, Centre for Radiation, Chemical and Environmental Hazards, Health Protection Agency, Chilton, Didcot, UK
a2 South East Regional Office, Health Protection Agency, South East Region, London, UK
a3 Gastrointestinal, Emerging and Zoonotic Infections Department, Centre for Infection, Health Protection Agency, London, UK
a4 Virus Reference Laboratory, Centre for Infection, Health Protection Agency, London UK
An outbreak of gastroenteritis affected at least 240 persons who had eaten at a gourmet restaurant over a period of 7 weeks in 2009 in England. Epidemiological, microbiological, and environmental studies were conducted. The case-control study demonstrated increased risk of illness in those who ate from a special ‘tasting menu’ and in particular an oyster, passion fruit jelly and lavender dish (odds ratio 7·0, 95% confidence interval 1·1–45·2). Ten diners and six staff members had laboratory-confirmed norovirus infection. Diners were infected with multiple norovirus strains belonging to genogroups I and II, a pattern characteristic of molluscan shellfish-associated outbreaks. The ongoing risk from dining at the restaurant may have been due to persistent contamination of the oyster supply alone or in combination with further spread via infected food handlers or the restaurant environment. Delayed notification of the outbreak to public health authorities may have contributed to outbreak size and duration.
(Accepted October 26 2011)
(Online publication December 01 2011)