NoVs are the major cause of acute nonbacterial human gastroenteritis, being transmitted from food or from person to person via a fecal-oral route, affecting population all over the world.
Indirect evidence in epidemiological studies shows that the virus transmission can be airborne, such as in explosive vomiting occurred during the disease. Transmission can also happen via water reservoir when groundwater is contaminated.
NoVs infect persons of all ages. Although NoV disease outbreaks are reported year-round, they peak during months with cold weather in temperate climates. Norovirus can spread quickly in enclosed places like daycare centers, nursing homes, schools, and cruise ships.
Clinical NoV infection generally has an incubation of 24–48 h and is characterized by acute onset of nausea, vomiting, abdominal cramps, myalgias, and non-bloody diarrhea.
NoV illness can present with relatively severe symptoms of vomiting and non-bloody diarrhea, with symptoms usually resolving in 2–3 days.
It only takes a very small amount of norovirus particles (fewer than 100) to make the person sick. People with norovirus illness shed billions of virus particles in their stool and vomit and can easily infect others.
Norovirus infection
