People infected with norovirus are contagious from the moment they start feeling ill and remain so for at least 3 days after recovery. However, some individuals can continue to be contagious for up to 2 weeks or even longer after symptoms have resolved
. The virus can be shed in stool for two weeks or more, and in immunocompromised patients, viral shedding may persist for months
. During the contagious period, norovirus can be transmitted through direct contact with an infected person, contact with contaminated surfaces or objects, and ingestion of contaminated food or water. Good hand hygiene, especially thorough handwashing with soap and water, is critical to prevent spread, as alcohol-based sanitizers are less effective against norovirus
. In summary:
- Contagious from onset of symptoms until at least 3 days after recovery
- Some people remain contagious up to 2 weeks or more post-recovery
- Immunocompromised individuals may shed virus for months
- Virus can be present in stool for weeks after symptoms end
- Handwashing and surface disinfection are key to controlling spread
This means people should avoid preparing food or attending work, school, or daycare while symptomatic and for at least 3 days after recovery to reduce transmission risk
