Norovirus symptoms typically begin 12 to 48 hours after exposure and usually last about 1 to 3 days. Most people recover completely without treatment within this time frame

. Some sources specify that symptoms can last from 12 to 60 hours, with the illness generally resolving within 1 to 2 days, though diarrhea may persist slightly longer

. After symptoms resolve, individuals can still shed the virus in their stool for several weeks, potentially remaining contagious during this period

. People with weakened immune systems or other medical conditions might experience symptoms for a longer duration or have prolonged viral shedding

. In summary:

• Symptom onset: 12 to 48 hours after exposure
• Duration of symptoms: typically 1 to 3 days (often 1 to 2 days)
• Viral shedding and contagiousness: can continue for weeks after recovery
• Longer duration possible in vulnerable populations

Hydration is key during the illness, and people are advised to stay home until at least 48 hours after symptoms have passed to prevent spreading the virus