Epidemiological and molecular analysis of a waterborne outbreak of norovirus GII.4

Guangdong Provincial Centre for Disease Control and Prevention, Guangdong, China.
Epidemiology and Infection (Impact Factor: 2.49). 03/2012; 140(12):1-8. DOI: 10.1017/S0950268812000374
Source: PubMed

ABSTRACT SUMMARYContaminated water is one of the main sources of norovirus (NoV) gastroenteritis outbreaks globally. Waterborne NoV outbreaks are infrequently attributed to GII.4 NoV. In September 2009, a NoV outbreak affected a small school in Guangdong Province, China. Epidemiological investigations indicated that household use water, supplied by a well, was the probable source (relative risk 1·9). NoV nucleic acid material in concentrated well-water samples was detected using real-time RT-PCR. Nucleotide sequences of NoV extracted from diarrhoea and well-water specimens were identical and had the greatest sequence identity to corresponding sequences from the epidemic strain GII.4-2006b. Our report documents the first laboratory-confirmed waterborne outbreak caused by GII.4 NoV genotype in China. Our investigations indicate that well water, intended exclusively for household use but not for consumption, caused this outbreak. The results of this report serve as a reminder that private well water intended for household use should be tested for NoV.

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Available from: John D Klena, Jan 16, 2014
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    • "NoV are characterized by high environmental stability, and only few infectious viral particles are necessary to induce disease (Teunis et al. 2008). Transmission of these highly infectious viruses occurs mainly via the faecal–oral route, by ingestion of contaminated water and food, particularly shellfish, soft fruits and vegetables, but also through person-to-person contact and exposure to fomites (Beuchat 2006; Hewitt et al. 2007; Le Guyader et al. 2009; Lopman et al. 2012; Matthews et al. 2012; Zhou et al. 2012). NoV outbreaks occur most commonly in semi-closed communities such as restaurants, nursing homes, hospitals, schools, day care centres and cruise chips (Fankhauser et al. 2002). "
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