RSV and Bronchiolitis in Babies: Symptoms, Care and Prevention

What it is

RSV (respiratory syncytial virus) is a common cold virus that peaks in fall and winter. Almost every child catches it by age 2. In older children and adults it's usually a cold. In babies it can spread to the small airways of the lungs, causing bronchiolitis: swelling and mucus that make breathing harder. Other viruses can cause bronchiolitis too.

How it usually goes

• Days 1-2: runny nose, sneezing, mild cough, maybe a low fever.
• Days 3-5: often the worst. Faster breathing, wheezing, a wet cough, more mucus, harder feeding.
• After that: slow improvement. The cough can last 2-4 weeks.
• Babies under 6 months, preterm babies, and those with heart or lung conditions or weak immune systems are most likely to need hospital care, mostly for oxygen or help with feeding.

Home care

• Clear the nose with saline drops and gentle suction before feeds and sleep.
• Offer smaller, more frequent feeds. A stuffy baby tires quickly.
• Count wet diapers. Fewer than usual means they need more fluid.
• A cool-mist humidifier may ease congestion.
• Fever medicine for comfort, dosed by weight; call before giving any under 12 weeks.
• Keep them on their back to sleep on a flat, firm surface, even when congested. Don't use inclined sleepers or propped mattresses.
• Keep smoke and vaping away from your baby.

Antibiotics, steroids and inhalers usually don't help bronchiolitis, and cough and cold medicines aren't safe for babies.

Watching breathing

Count breaths for a full minute while your baby is calm or asleep. Faster than about 60 a minute is too fast for a baby. Also look for ribs or the skin at the neck pulling in, nostrils flaring, grunting, or the head bobbing with each breath.

Prevention

Most babies can now be protected in one of two ways (usually not both): - A vaccine during pregnancy, given at 32-36 weeks during RSV season, passes protection to the baby. - A long-acting antibody shot for the baby, given before or during their first RSV season if the pregnant parent wasn't vaccinated, was vaccinated less than 2 weeks before birth, or the baby was adopted or born by surrogacy. Some higher-risk babies get a dose in their second season too.

Everyday steps also help: handwashing, keeping sick visitors away, and cleaning toys and surfaces. See the vaccines and visitors guides.

When to check in

• See the pediatrician if your baby is under 3 months and has cold symptoms, is feeding about half as much as usual, has fewer wet diapers, or has a fever lasting more than 2-3 days.
• Any fever of 100.4°F (38°C) or higher in a baby under 3 months needs a same-day visit.
• If your baby is struggling to breathe, pauses in breathing, or has blue or gray lips or skin, call 911.