Frequently Asked Questions

Noroviruses are found in the stool or vomit of infected people. People can become infected by:

• Having direct contact with an ill person.
• Eating foods or drinking liquids that are contaminated with Noroviruses.
• Touching surfaces or objects contaminated with Noroviruses and then touching their own mouth.

Norovirus can spread quickly in closed places like daycare centers, nursing homes, schools, and cruise ships. Most norovirus outbreaks happen from November to April in the United States.

Norovirus causes inflammation of the stomach intestines or both. This is called acute gastroenteritis.

The most common symptoms include:

• diarrhea
• throwing up
• nausea
• stomach pain
• fever
• headache
• body aches

A person usually develops symptoms 12 to 48 hours after being exposed to norovirus. Most people with norovirus illness get better within 1 to 3 days.

If you have norovirus illness, you can feel extremely ill and throw up or have diarrhea many times a day. This can lead to dehydration, especially in young children, older adults, and people with other illnesses.

Symptoms of dehydration:

• decrease in urination
• dry mouth and throat
• feeling dizzy when standing up

Children who are dehydrated may cry with few or no tears and be unusually sleepy or fussy.