From a Pediatrician: How RSV Affects a Child’s Lungs

Almost all children have had RSV, or respiratory syncytial virus, by the time they are 2 years old. RSV typically causes mild, cold-like symptoms such as congestion, coughing, sneezing, runny nose and fever; in infants, RSV might lead to irritability, decreased appetite and activity, and trouble breathing.

For most healthy children, this lung infection runs its course in about a week, but RSV can cause significant issues for infants and toddlers, particularly if they were born prematurely, have a lung or heart issue, or have a weakened immune system. RSV is the leading cause of infant hospitalization in the United States; the Centers for Disease Control and Prevention estimates that as many as 80,000 children younger than 5 are hospitalized each year because of RSV.

UNC Health pediatrician Edward Pickens, MD, explains what RSV does to a child’s lungs.

RSV’s Short-Term Effect on the Lungs

RSV affects the lungs in a few ways, the combination of which can be especially hard on infants and toddlers.

“RSV creates a lot of mucus, which plugs up the air passages,” Dr. Pickens says. “As a result, germs and viruses can get trapped in the lower respiratory tract, leading to a second lung infection, like pneumonia or bronchitis.”

Congestion and coughing also can cause the air passages to become swollen or irritated, making it more difficult to get air through the passages. Sometimes the passages can spasm, causing symptoms similar to an asthma attack.

“If your child is having to work really hard to breathe, to the point that you can see them using their chest muscles to get the air in and out, they should be checked out right away,” Dr. Pickens says. “It’s not just a problem of getting the air in but getting the air out as well. The mucus can trap the air in the lungs, and they can’t blow it out.”

Children experiencing extreme breathing difficulties may require oxygen in the hospital during an RSV infection. For some children, the asthma medication albuterol may provide symptom relief.

RSV’s Long-Term Effect on the Lungs

Because RSV can trap mucus in the lungs, many children develop another lung infection after RSV, and in the winter, when many viruses are circulating, it may seem that small children are constantly sick. For most children, multiple infections won’t cause long-term issues with the lungs.

A small number of children, however, will have damage from RSV in the airways, Dr. Pickens says. “Those kids may go on to have some lung problems later on.”

Children who have bronchiolitis as a result of RSV are more likely to develop asthma. Bronchiolitis causes swelling and irritation in the small airways known as the bronchioles. Wheezing—a high-pitched whistling or rattling sound during breathing—is a symptom of bronchiolitis and asthma, and it might show up in subsequent respiratory infections.

“There is a link between RSV bronchiolitis and later asthma, but it’s unclear if the virus causes the damage or if a genetic predisposition to asthma causes the child to have a harder time with RSV,” Dr. Pickens says.

If your child continues to wheeze, your pediatrician might recommend an asthma treatment such as albuterol.

How to Help a Child Who Has RSV

There are a few things you can do to help your child during an RSV infection. Placing a humidifier in your child’s bedroom or having your child play in a bathroom made steamy by a hot shower can help clear mucus and make it easier to breathe, and you can use a bulb syringe to remove mucus from the nose. Otherwise, you should focus on keeping your child hydrated and rested.

“Make sure kids take it easy during the recovery process,” Dr. Pickens says, noting that each child’s recovery is different. “Some kids need several weeks to get over RSV, with a few weeks of coughing and mucus, while others can return to activities sooner.”

If you have a young infant, talk to your pediatrician about immunization against RSV.

“Beyfortus, or nirsevimab, has been approved for use in infants under 8 months,” Dr. Pickens says. “It’s designed to be given at the beginning of RSV season, in October, but it can be administered at any time before the season ends, usually in March.”


Worried your child may have RSV? Talk to your doctor. If you need a doctor, find one near you.