Waterborne Norovirus Outbreaks

Abstract

Noroviruses (NoVs) are the most common nonbacterial causative agents of waterborne outbreaks. Due to the mild and short-lived disease of gastroenteritis, even large epidemics may go unnoticed, since patients do not necessarily visit a doctor. NoVs have several means by which to survive both in the environment and in a population. The nonenveloped small virus retains its infectivity in the environment, and particularly in cold water, for a long time. Unlike most enteric viruses, it causes disease both in children and adults. A large number of genotypes combined with a small infective dose and short-term immunity guarantee efficient circulation of these viruses. The world of NoVs has been revealed to us predominantly by molecular methods. Having learned to detect these viruses first in patients, the emphasis is now in searching for methods sensitive enough to find them in environmental samples. In this review, the latest methods and their use in monitoring of these viruses are discussed.

Keywords: :

• gastroenteritis
• molecular epidemiology
• norovirus
• waterborne outbreak

Acknowledgements

I want to thank Emeritus Professor C-H von Bonsdorff for critical review of the manuscript. I also thank the personnel in the Helsinki University Hospital, Laboratory Services (HUSLAB), Department of Virology. Research was supported by grants from European Commission contract (Providing tools to prevent emergence of enteric viruses, EVENT, FP6-SP22-CT-2004-502571), and the Jenny and Antti Wihuri Foundation.

Additional information

Funding

I want to thank Emeritus Professor C-H von Bonsdorff for critical review of the manuscript. I also thank the personnel in the Helsinki University Hospital, Laboratory Services (HUSLAB), Department of Virology. Research was supported by grants from European Commission contract (Providing tools to prevent emergence of enteric viruses, EVENT, FP6-SP22-CT-2004-502571), and the Jenny and Antti Wihuri Foundation.