Everything you need to know about RSV in babies and toddlers

RSV is an infection of the lungs and respiratory tract. There are two different strains of the virus, and they can lead to different levels of severity. According to the Centers for Disease Control and Prevention (CDC), almost all children catch the virus by the time they’re two, and an estimated 57,000 children under five are hospitalized each year in the United States for RSV. Much like cold and flu season, RSV season lasts from November through April. And the virus doesn't discriminate, affecting all age groups, from babies to the elderly.

RSV is highly contagious and can be spread in many different ways. “Droplets from a runny nose, coughing and sneezing are all common ways that RSV is spread,” says TJ Gold, a paediatrician at Tribeca Pediatrics in New York City. Gold says the virus can also live on surfaces in the home, such as doorknobs, countertops, cribs and baby toys, for several hours. According to the CDC, if your baby has the virus, she can be contagious for three to eight days after getting infected.

One of the tricky things about RSV is that you don’t see symptoms until about four to six days after your child is exposed, but there are symptoms that parents should watch for. “RSV is a virus that produces a lot of mucus,” says Gold. If your baby has a lot of mucus, that’s a classic first sign of RSV—though that’s also symptomatic of a cold. Unlike a cold, though, if your baby has RSV, she could have difficulty breathing.

The most common symptoms of RSV are:

• A runny nose
• Coughing
• Sneezing
• Wheezing or difficulty breathing (listen for a high-pitched noise when your baby is breathing, and watch your child’s chest to see if her skin or muscles pull in with each breath)
• A fever
• Decreased appetite

While you may start to notice these symptoms after the incubation period is over (three to four days after exposure), Gold says that RSV doesn’t hit its peak until day five or six. For most kids, RSV symptoms last for one to two weeks, but you may notice a residual cough for weeks after other symptoms have cleared up.

Given the early start to the flu season and the ongoing pandemic, it's also important to monitor your child's symptoms carefully to rule out influenza or COVID-19, as respiratory viruses tend to present similarly. According to the Cleveland Clinic, looking out for these symptoms could give you a better handle on what you're dealing with:

• Wheezing: Most common in RSV cases
• High fever; severe nausea and/or vomiting: Most common with the flu
• Long-term effects: Most common with COVID

Children, especially those in childcare settings, can be co-infected with one or more viruses, which makes getting vaccinated against the flu and COVID that much more vital.

When doctors examine a patient who is suspected of having RSV, they look for a lot of secretions, such as mucus. A doctor will also listen to a baby’s chest. Patients with RSV will have scattered wheezing in their chests, and many will pant or breathe extremely fast, says Gold. A nasal swab is done to confirm if a child has RSV. An oxygenation test, done on the finger, may also be performed to see how well your child’s lungs are functioning.

Since RSV is a virus, antibiotics aren’t a treatment option. There is an RSV-specific inhaled breathing treatment of humidified saline that your doctor can administer through a mask and nebulizer machine. It’s not 100 percent effective, says Gold, but it can help with RSV-related breathing issues. However, the treatment has to be administered at your doctor’s office. Acetaminophen or ibuprofen can be used to help reduce a fever and relieve pain, but check the label to make sure that you’re giving the right dose for your child’s weight.

As with many other viruses, RSV needs to run its course, which, unfortunately, can be a long while. “Residual coughing and sneezing can last for four to six weeks,” says Gold. For some kids, especially babies under six months, the symptoms of RSV can worsen, and a hospital stay may be necessary to treat their symptoms. If your baby isn’t breastfeeding or bottle feeding well, they may become dehydrated and need to be hospitalized and put on an IV to restore her fluid levels. If your child is breathing at twice their normal rate, take them to the doctor or the nearest hospital. With RSV, it’s not uncommon for your baby’s oxygen levels to be low, so they might need to be put on oxygen in the hospital.

Besides lots of TLC, these strategies, combined with plenty of rest, can help your baby feel better.

• Use a humidifier: Concentrated, humidified air can help ease your baby’s coughing and stuffy nose.
• Offer plenty of liquids: Rapid breathing can cause babies to dehydrate. Your baby probably won’t want to eat as many solids, so try breastfeeding or bottle feeding more frequently for shorter periods of time.
• Use the shower to turn your washroom into a steam room: The steam can serve as a natural way to improve breathing.

Gold says to watch for the main symptoms of RSV, such as difficulty breathing and poor feeding, to worsen. When babies have difficulty breathing, it’s harder for them to feed from the breast or bottle. “Children can get dehydrated, so parents should watch for decreased urine output and poor feeding as signs that RSV is worsening,” says Gold. If you notice these symptoms, visit your doctor or the emergency room immediately.

RSV can reduce your child’s immune function and make them more susceptible to other viruses. According to the CDC, pneumonia and bronchiolitis are two illnesses that children with RSV can catch. With pneumonia, the lungs become infected, while bronchiolitis involves inflammation of the small airways in the lungs. Viral pneumonia, like RSV, is a virus that just has to run its course. But if your baby has bacterial pneumonia, your paediatrician will prescribe antibiotics. Bacterial pneumonia can be quite serious and may require hospitalization, says Gold.

Children and babies that develop bronchiolitis, a viral inflammation of the lung's airways, may find relief from symptoms through saline drops and acetaminophen. Watch out for signs of dehydration and laboured breathing because, like RSV, your child may need a hospital stay to restore their fluids and stabilize their oxygen levels.

As with colds, there isn’t one magical thing you can do to prevent RSV, but you can take measures to minimize your risk.

• Wash your hands: Since you’re preparing your baby’s food and doing pretty much everything else for them, be sure to wash your hands. Wash them before you pick up your baby and whenever you handle anything that’s going in their mouth.
• Keep surfaces clean: Since RSV lives on surfaces, be sure to wipe down anything that your baby will come in contact with, including toys.
• Keep your baby away from sick people: You wouldn’t intentionally let your baby hang around with other babies or grown-ups who are sick, but once you know someone is ill, it’s time to go.

If your baby has picked up RSV before, they can still get it again—even during the same RSV season—so be proactive about prevention.

The development of an RSV vaccine has been a long time coming (read about its fraught history here) and a couple of promising versions are currently in trials in older adults, but it could be another few years before one becomes widely available.

There is an injection called Synagis that contains virus-fighting antibodies. It’s only given to babies who are at high risk of developing complications from RSV. These include babies who were born prematurely or suffer from congenital heart disease or chronic lung disease. Unlike a vaccine, babies who receive Synagis need to get an injection once a month, every month, during RSV season. Your paediatrician will be able to tell you if Synagis is suitable for your baby.

Remember, you know your baby best. If your intuition tells you that something isn’t right, act on it and see your paediatrician for a proper diagnosis.

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