Norovirus (Stomach Bug) in Babies & Toddlers
Content reviewed against published CDC, CDC, AAP guidelines
Last reviewed:
Norovirus is the most common cause of acute gastroenteritis (stomach flu) in people of all ages. It causes sudden onset of vomiting and diarrhea and is extremely contagious. It spreads rapidly through families, daycare centers, and anywhere people are in close contact. While usually self-limiting, it can cause dangerous dehydration in young babies.
Key takeaways
- Norovirus is the most common cause of acute gastroenteritis (stomach flu) in people of all ages.
- Duration: Typically 1-3 days. Vomiting usually resolves within 24 hours, diarrhea may persist 2-3 days longer. Most recover fully within 72 hours.
- Go to ER if: No wet diaper for 6+ hours in baby, or 8+ hours in toddler
- No vaccine currently available
Symptoms
How It Presents by Age
0-6 months
Vomiting and watery diarrhea that can quickly lead to dehydration. May present primarily with irritability and poor feeding. Breastfed babies may be somewhat protected.
Risk level: Moderate to high (dehydration risk)
6-12 months
Sudden onset vomiting (often the first sign), followed by diarrhea. May refuse to eat or drink. Rapid dehydration is the main concern.
Risk level: Moderate
1-3 years
Classic sudden vomiting and diarrhea. Often the whole family gets sick. Child may vomit several times in the first hours then transition to diarrhea.
Risk level: Low to moderate
3-5 years
Similar to adults — sudden vomiting, diarrhea, and stomach cramps. Usually resolves faster than in younger children.
Risk level: Low
Treatment
Oral rehydration
Small, frequent sips of oral rehydration solution (Pedialyte). Start with 1 teaspoon every 5 minutes and gradually increase as tolerated.
Wait and reintroduce
Wait 30-60 minutes after vomiting stops before offering fluids. Then start with tiny amounts.
Continue breastfeeding
Breastfed babies should continue nursing. Breast milk is easy to digest and provides hydration.
Ondansetron
A single dose of ondansetron (Zofran) can be prescribed to stop vomiting and allow oral rehydration.
IV fluids
For moderate to severe dehydration when oral rehydration fails.
Home Care
- Wait 30-60 minutes after vomiting before offering any fluids
- Start with 1 teaspoon of Pedialyte every 5 minutes, increase slowly
- Continue breastfeeding in short, frequent sessions
- Once vomiting stops for a few hours, offer bland foods
- Avoid dairy (except breast milk) for 24-48 hours if diarrhea persists
- Use soap and water for handwashing — hand sanitizer does NOT kill norovirus
- Clean contaminated surfaces with bleach solution (5-25 tablespoons per gallon)
- Keep separate towels and washcloths for the sick child
- Wash soiled clothing and linens on the hottest setting
When to Worry
Go to the ER if:
- No wet diaper for 6+ hours in baby, or 8+ hours in toddler
- Sunken fontanelle, sunken eyes, no tears
- Baby is limp or very lethargic
- Vomiting bile (green/yellow) — may indicate bowel obstruction
- Severe abdominal pain
- Bloody stool
- Baby unable to be roused or very confused
- Signs of severe dehydration — mottled skin, cold extremities, rapid heart rate
Call your doctor if:
- Baby under 6 months with vomiting and diarrhea
- Unable to keep fluids down for 8-12 hours
- Diarrhea lasting more than 5 days
- Fever over 102°F lasting more than 2 days
- Signs of mild dehydration (dry lips, fewer wet diapers)
- Blood in stool or vomit
Keep an eye on:
- No wet diaper for 4-6 hours (babies) or 8 hours (toddlers)
- No tears when crying
- Vomiting continuing beyond 24 hours without any fluids staying down
- Blood in vomit or stool
- Extreme drowsiness or irritability
- Sunken fontanelle in infants
Prevention
- Thorough handwashing with soap and water (hand sanitizer is NOT effective)
- Clean and disinfect surfaces with chlorine bleach solution
- Wash contaminated laundry at highest temperature with detergent
- Isolate sick family members as much as possible
- Do not prepare food for others while sick and for 48 hours after recovery
- Wash fruits and vegetables thoroughly
- Keep children home from daycare for 48 hours after last episode of vomiting/diarrhea
Contagion & Incubation
Incubation
12-48 hours (often very rapid onset)
Contagious for
From onset of symptoms until at least 48 hours after symptoms resolve, though virus can be shed in stool for 2 weeks or more
Duration
Typically 1-3 days. Vomiting usually resolves within 24 hours, diarrhea may persist 2-3 days longer. Most recover fully within 72 hours.
Frequently asked questions
How long does norovirus (stomach bug) last?
How does norovirus gastroenteritis spread?
When should I take my baby to the ER?
Can norovirus gastroenteritis be prevented?
When can my child return to daycare?
Sources
All content follows our editorial policy and is reviewed against published clinical guidelines.
2,705 evidence-based guides6 authoritative medical sources
Related Illnesses
Bottom line
Norovirus (Stomach Bug) is a viral illness that typically resolves on its own. Seek emergency care if no wet diaper for 6+ hours in baby, or 8+ hours in toddler.
Trust your instincts. If something feels wrong, reach out to your pediatrician. Worrying about your baby means you care — that is a good thing.