Norovirus

Virus and disease overview

Norovirus, more commonly known as the “winter vomiting disease virus”, is the leading cause of acute gastroenteritis in all age groups and often causes large, rapidly spreading outbreaks, especially in settings such as schools and nursing homes. This highly contagious virus tends to peak during the winter months, when close indoor contact facilitates its transmission. Due to its genetic diversity, norovirus is classified into seven genogroups, with genogroup II being the primary culprit of diarrheal illness in humans.

Detection in Wastewater and Public Health Relevance

Norovirus is shed in large quantities in the stool of infected individuals, including asymptomatic carriers, making it easily detectable in wastewater. Because of its high prevalence and typically self-limiting nature, norovirus infections are only required to be reported by specialized medical laboratories. Most infections last only a few days, and stool testing for norovirus is relatively rare, making wastewater monitoring a valuable tool for tracking the spread of norovirus. By monitoring norovirus levels in wastewater, public health authorities can receive early warning of outbreaks, often before they are detected by clinical surveillance. This approach enables proactive public health responses, including targeted hygiene campaigns, and helps manage the burden on healthcare facilities during peak periods.