Your baby is coughing, breathing faster than usual, and clearly worn out. Could it be RSV? Every year this virus leads to thousands of doctor visits and hospitalizations among young children.

RSV (respiratory syncytial virus) is the most common cause of serious respiratory infection in children under two years of age. Most children only get mild cold symptoms, but for the very youngest, the infection can develop into bronchiolitis — inflammation of the small airways that causes breathing difficulties.

Here you'll find an overview of symptoms, treatment, and prevention based on updated recommendations from the CDC and AAP.

What Is RSV?

RSV is a highly contagious respiratory virus that affects people of all ages. In older children and adults, it usually only causes a cold. In infants, the virus can attack the lower airways and cause bronchiolitis.

Almost all children are infected with RSV during the first two years of life. Around 1–3 percent of infected infants need hospitalization.

RSV Season

RSV has a clear seasonal pattern with outbreaks typically from November through March. The peak is usually in December–February. Outbreaks often follow a cyclical pattern with more severe seasons every other year.

Hospitals see a clear increase in admissions of infants with breathing difficulties during this period.

RSV spreads through droplet transmission (coughing, sneezing) and contact transmission (hands, surfaces). The virus can survive on surfaces for several hours.

Symptoms of RSV

Symptoms typically develop gradually over a few days.

Early Symptoms (Days 1–3)

The first signs resemble a common cold:

Runny or stuffy nose
Mild cough
Low-grade fever
Reduced appetite
Fatigue

Symptoms of Bronchiolitis (Days 3–5)

In children under one to two years, the infection can move down to the lower airways. You may then see:

Rapid breathing — the baby is breathing noticeably faster than normal
Wheezing — a whistling sound when breathing out
Retractions — skin pulling in between the ribs, under the chest, or at the base of the throat when breathing in
Nasal flaring — nostrils widening with each breath
Difficulty feeding — the baby doesn't have the energy to nurse or bottle-feed normally
Coughing — can be wet or dry

Persistent Cough After RSV

After the infection itself is over, the child may continue to cough for two to four weeks. The mucous membranes in the airways need time to heal. This cough is usually not a sign that the child is still contagious or needs treatment.

Who Is Most at Risk?

Some children have a higher risk of a severe course:

Infants under 2–3 months — have the highest disease burden
Premature babies — especially those born before week 32
Children with congenital heart disease or chronic lung disease
Children with neurological conditions that affect breathing muscles
Children with Down syndrome
Children with weakened immune systems

Older siblings are one of the most important sources of infection. An older child with a mild cold can transmit RSV to the baby, who can become seriously ill. Be especially careful about hand hygiene during RSV season.

Treatment of RSV

There is no medication that kills RSV. Treatment focuses on relieving symptoms while the child's immune system fights the infection.

Home Treatment

Most children with RSV can be treated at home. Here are the most important measures:

Fluids: Give frequent, small feedings. Children with a stuffy nose often can't eat as much as usual. Offer breast or bottle more frequently, in shorter sessions.

Saline drops in the nose: A few drops of saline solution (0.9% NaCl) in each nostril loosens mucus and makes breathing easier. Use a nasal aspirator to suction out mucus in the youngest children.

Elevated head position: Place a rolled-up towel under the mattress (not under the baby) so the head lies slightly higher. This can make breathing easier.

Rest: Let the child rest. Avoid activity that makes the child more short of breath.

Use saline drops in the nose right before feedings. This makes it easier for the baby to breathe through the nose while eating.

Fever Reducers

If the child has a fever and is clearly uncomfortable, you can give acetaminophen (Tylenol) following the recommended dosing for the child's weight and age. Read more in our guide on fever in children.

What Should You NOT Do?

Corticosteroids are not recommended for bronchiolitis — they have no documented effect
Cough syrup and expectorants are not recommended for young children
Antibiotics do not help against viruses (only for confirmed bacterial secondary infection)

Hospital Treatment

Children admitted to the hospital receive monitoring of breathing and oxygen levels. If needed, they may receive:

Extra oxygen via nasal cannula
IV fluids if they are unable to drink enough
In severe cases: breathing support with CPAP or ventilator

Hospital stays for RSV typically last three to five days.

Parent caring for a child in a warm, calm home setting

When Should You Contact a Doctor?

Trust your instincts. If you are worried about your child, it is always right to seek help.

Contact your pediatrician or urgent care if the child: - Is breathing faster than normal or with effort - Has retractions in the chest or at the base of the throat - Won't eat or is drinking less than half the normal amount - Has fewer wet diapers than usual (sign of dehydration) - Is unusually limp, tired, or difficult to wake - Has had a fever for more than 3 days - Has a fever and is under 3 months old

Call 911 if the child:

Has blue or gray lips, tongue, or fingertips — sign of oxygen deficiency
Stops breathing — even brief breathing pauses in infants are serious
Is limp or unresponsive to stimulation
Has severe breathing difficulty where the child is using all their effort to breathe

The younger the child, the faster you should act. A baby under three months with respiratory symptoms should always be assessed by a doctor.

Prevention: How to Protect Your Baby

RSV is highly contagious, and you cannot avoid it entirely. But there is a lot you can do to reduce the risk.

Everyday Hygiene

Wash hands frequently — use soap and water for at least 20 seconds
Clean surfaces — wash toys, door handles, and touch surfaces regularly during RSV season
Cough and sneeze into your elbow — teach older siblings good cough hygiene
Avoid touching your face — the virus enters through the eyes, nose, and mouth

Protect the Youngest

Limit visitors to newborns during RSV season, especially from people with colds
Avoid large gatherings with babies under three months during winter
Ask visitors to wash their hands before touching the baby
Keep sick older siblings away from the baby as much as possible

It is perfectly fine to set limits. If grandma or a relative has a cold, it is sensible to postpone the visit for a few days. Most people understand that it is about the baby's health.

Breastfeeding Provides Protection

Breast milk contains antibodies that strengthen the baby's immune system. Children who are breastfed have a lower risk of serious RSV infection. If your child does get sick, frequent breastfeeding can also help keep fluid intake up.

For newborns and premature babies, it is especially important to limit exposure during RSV season. Read more about newborn care.

Vaccines and Preventive Treatment

In recent years, several new options have become available to protect babies against serious RSV infection.

Nirsevimab (Beyfortus) — Long-Acting Antibody

Nirsevimab is a long-acting antibody that provides protection for up to five months with a single injection. It is FDA-approved for:

Newborns and infants in their first RSV season
Children under two years with high risk

Unlike palivizumab (which requires monthly injections), nirsevimab is given as a single dose. Talk with your pediatrician about availability and eligibility.

Palivizumab (Synagis) — For High-Risk Groups

Palivizumab is an antibody given as a monthly injection throughout RSV season. It is reserved for children at highest risk:

Very premature babies
Children with severe heart disease
Children with chronic lung disease
Children with severe immunodeficiency

Your pediatrician will assess whether your child qualifies.

Abrysvo — Vaccine for Pregnant Women

Abrysvo is a vaccine that can be given to pregnant women between gestational weeks 32 and 36. Antibodies are transferred to the baby via the placenta and provide protection during the first months of life — exactly when the baby is most vulnerable.

The vaccine is FDA-approved and available in the United States. Talk with your doctor or midwife if you are interested. Read our full guide: RSV Vaccine During Pregnancy.

RSV Vaccines for Older Adults

For grandparents and other older adults over 60, there are RSV vaccines available (Arexvy, Abrysvo). These protect the older person themselves, but also indirectly help protect infants by reducing transmission within the family.

The CDC recommends RSV prevention measures for infants — either through vaccination during pregnancy or antibody treatment for newborns. Talk with your pediatrician to find out what is right for your baby.

Frequently Asked Questions

How long is the child contagious with RSV?

Children with RSV are usually contagious for three to eight days after symptoms start. Young infants and children with weakened immune systems may be contagious for up to four weeks.

Can a child get RSV more than once?

Yes. RSV does not confer lasting immunity. The child can be reinfected, but repeated infections tend to cause milder symptoms as the body builds up some resistance.

How long does RSV last?

Acute symptoms typically last one to two weeks. Coughing and fatigue can persist for three to four weeks after the infection is over. If the child has not improved after two weeks, you should contact the doctor.

Do saline nebulizer treatments help?

Saline nebulizer treatments can help loosen mucus, but the effect is limited. It is more important to make sure the child gets enough fluids and rest. Talk with your doctor if you are considering nebulizer treatments.

Can RSV be prevented with vitamins?

There is no evidence that vitamin supplements protect against RSV. Vitamin D is recommended for all infants, but for bone health — not to prevent respiratory infections.

Should older siblings stay home from daycare?

It is not necessary to keep healthy siblings home. But be especially careful about hand hygiene, and try to limit close contact between a sibling with a cold and the baby.

When can the child return to daycare?

The child can return to daycare when their general condition is good, the fever is gone, and they are able to participate in normal activities. A cough alone is not a reason to keep the child home, as long as they are otherwise doing well.

Caring parent with child in a calm, warm atmosphere

Useful Tools on Babysential

Health log — track symptoms and illness
Pediatrician visit checklist

RSV in Children: Symptoms, Treatment, and Prevention