0 a very infectious virus that makes people vomit and have diarrhoea (= waste from the body that is more liquid than usual)
Staff from residential institutions, hospitals, day-care centres and schools, and also parents should be made aware that norovirus is highly contagious.
This outbreak investigation illustrates the importance of norovirus as a cause of waterborne illness and the additional exacerbation through person-to-person transmission in closed settings.
Sampling of water for norovirus analysis was carried out 3-4 weeks after the outbreak, which may have led to the negative results.
An estimate of costs for patients with campylobacter, salmonella or norovirus infections was, in total, 10 -17 % of the costs of gastroenteritis.
In foodborne outbreaks norovirus was common, due to contamination of food by food handlers.
Of three foodborne norovirus outbreaks, where a number of suspected food items were tested, virus was not detected in any of them.
Four of these outbreaks were caused by norovirus, for the remaining five no conclusive causative agent was found.
Indicators of faecal contamination were found in samples from the private untreated water supply, but norovirus could not be identified.
