Bronchiolitis in Babies
Content reviewed against published AAP, CDC, WHO guidelines
Last reviewed:
Bronchiolitis is a common lower respiratory tract infection in infants and young children, most often caused by RSV. It causes inflammation and congestion in the small airways (bronchioles) of the lungs, leading to wheezing and difficulty breathing. It is the most common reason for hospitalization in infants under 1 year.
Key takeaways
- Bronchiolitis is a common lower respiratory tract infection in infants and young children, most often caused by RSV.
- Duration: Typically peaks around day 3-5, then gradually improves over 7-10 days. Cough may persist for 2-4 weeks.
- Go to ER if: Blue lips or face
- A vaccine or immunization is available
Symptoms
How It Presents by Age
0-3 months
May present with apnea, poor feeding, and lethargy before significant cough or wheeze develops. At highest risk for severe disease.
Risk level: High
3-6 months
Classic presentation with progressive congestion, cough, and wheezing over 3-5 days. Peak symptoms around day 3-5.
Risk level: Moderate to high
6-12 months
Wheezing and cough with variable severity. Most manage at home with close monitoring.
Risk level: Moderate
1-2 years
Generally less severe. May present similarly to asthma/reactive airway disease on repeat episodes.
Risk level: Low to moderate
Treatment
Supportive care
No medications have been shown to help bronchiolitis. Antibiotics, steroids, and bronchodilators are NOT recommended.
Nasal suctioning
Gentle superficial suctioning before feeds and sleep. Deep suctioning is not recommended.
Hydration
Small frequent feeds. May need to offer half the normal volume twice as often.
Monitoring
Watch for signs of worsening: breathing rate, retractions, wet diapers, and feeding amounts.
Hospital care
Oxygen support, nasogastric or IV fluids if needed. High-flow nasal cannula for moderate-severe cases.
Home Care
- Saline nasal drops and gentle suctioning before feeds
- Cool-mist humidifier in the room
- Keep baby slightly elevated (raise head of mattress safely)
- Small, frequent feeds — offer breast/bottle every 2 hours
- Watch for wet diapers (at least 3-4 per day)
- Keep environment smoke-free
When to Worry
Go to the ER if:
- Blue lips or face
- Pauses in breathing
- Severe retractions — skin sucking in deeply between ribs or at the neck
- Baby is limp or very difficult to rouse
- Unable to feed at all
- Grunting with every breath
Call your doctor if:
- Symptoms are not improving by day 5-7
- Baby is taking less than half their feeds
- Fever develops after initial improvement (may suggest secondary infection)
- Fewer than 3 wet diapers in 24 hours
- You are concerned about your baby's breathing
Keep an eye on:
- Breathing rate over 60 breaths per minute
- Visible ribs or belly breathing
- Baby working hard to breathe
- Feeding less than half of normal
- Fewer wet diapers than usual
Prevention
- Nirsevimab (Beyfortus) for all infants entering their first RSV season
- Handwashing before handling baby
- Avoid sick contacts, especially during RSV season
- Breastfeeding provides protective antibodies
- Avoid cigarette smoke exposure
- Limit exposure to older siblings' daycare germs when possible
Contagion & Incubation
Incubation
2-8 days depending on the causative virus
Contagious for
Typically 3-8 days, but young infants may shed virus for up to 3-4 weeks
Duration
Typically peaks around day 3-5, then gradually improves over 7-10 days. Cough may persist for 2-4 weeks.
Frequently asked questions
How long does bronchiolitis last?
How does acute bronchiolitis spread?
When should I take my baby to the ER?
Can acute bronchiolitis 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
Bronchiolitis is a viral illness that typically resolves on its own. Seek emergency care if blue lips or face.
Trust your instincts. If something feels wrong, reach out to your pediatrician. Worrying about your baby means you care — that is a good thing.