Waterborne outbreak of gastroenteritis in a religious summer camp in Norway, 2002

Abstract

In July 2002 an outbreak of acute gastroenteritis occurred in a camp facility in western Norway during a 10-day seminar, with around 300 guests staying overnight and several day-time visitors. Environmental and epidemiological investigations were conducted to identify and eliminate the source of the outbreak, prevent further transmission and describe the impact of the outbreak. Of 205 respondents, 134 reported illness (attack rate, 65%). Multivariate analysis showed drinking water and taking showers at the camp-site to be significant risk factors. Secondary person-to-person spread among visitors or outside of the camp was found. Norovirus was identified in 8 out of the 10 stool samples analysed. Indicators of faecal contamination were found in samples from the private untreated water supply, but norovirus could not be identified. 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. Since aerosol transmission through showering contributed to the spread, intensified hygienic procedures such as isolation of cases and boiling of water may not be sufficient to terminate outbreaks with norovirus.

An investigation of a waterborne outbreak caused by microbiological contamination of the drinking water supply system

“…It is indeed biologically plausible that the vehicle for the outbreak caused by Norovirus and Rotavirus is the drinking water (16). Besides the multiple pathogens identified, we were able to demonstrate high attack rates, while the epidemic curve was suggestive of a common point source, which is compatible with findings in other waterborne outbreaks described before (17,18,19). Thus, these results, combined with the events, brought to light during the environmental investigation, strongly suggest that the vehicle of the outbreak was the contaminated drinking water from the water distribution system.…”

Norovirus gastroenteritis

“…Waterborne epidemics have occurred in such locations as a summer camp in Norway [37] and a Swiss ski resort [38]. In both of these epidemics the water supply had been contaminated by a break in a nearby sewer.…”

Presence of Enteric Viruses in Source Waters for Drinking Water Production in the Netherlands

“…Although the exact role of reoviruses as human pathogens remains unclear and they mainly cause mild and asymptomatic illness, more severe illness, like meningitis, has been reported (17,42). Numerous waterborne outbreaks have previously been described, particularly caused by noroviruses and rotaviruses (13,15,16,25,26,33,46).…”