As COVID-19 cases in children continue to climb, pediatricians warn that parents and caregivers should not overlook another respiratory illness that recently surged unexpectedly: respiratory syncytial virus, or RSV.
Both RSV and COVID-19 ― particularly the delta variant ― are highly contagious. And both can cause cold or flu-like symptoms in children. Which means they’re sometimes difficult to tell apart.
So here’s what parents need to know.
RSV is usually mild — but not in babies
RSV is a seasonal virus that primarily affects children, and it’s really common. Most kids have had the virus by the time they turn 2. And for kids who are toddler-age and older, symptoms tend to be mild, like a common cold.
However, babies 1 year and younger are much more susceptible to serious illness. The virus can spread to their respiratory tract, causing pneumonia or bronchiolitis (basically, inflammation of their airways) that can make it difficult for them to breathe.
“By age 2, at least 90% of children have had one infection with RSV,” Dr. Octavio Ramilo, chief of infectious diseases at Nationwide Children’s Hospital, told HuffPost. “It’s estimated that during their first year of life, 50 to 60% of children get infected with RSV. The problem is that 3% of those kids get very sick, because it goes to the lungs.”
RSV and COVID cause slightly different symptoms
Mild RSV symptoms include a runny nose, dry cough or sore throat, low-grade fever, sneezing or a headache.
Mild COVID-19 symptoms in kids are pretty similar: fever, chills, cough. But many kids, like adults, experience a loss of taste or smell — and it’s unclear how much that’s the case with RSV. (Again, this is partly because babies are often the ones getting sick with RSV, and they’re not able to vocalize what they’re smelling or tasting.) There’s also some indication that gastrointestinal issues, like vomiting, tend to be associated more with COVID than RSV.
Since the symptoms are so similar, testing is key — and both COVID tests and RSV tests are available.
Experts don’t fully know why cases surged this summer
RSV usually peaks in the fall and winter and declines in the spring, but there was an unexplained surge this summer that seems to be winding down now. Experts don’t know exactly what was behind it — or what it means for what’s to come — but they do have theories.
One is that cases increased because children were spending time together again over the summer, often without masks, after many months of staying home. Like COVID-19, RSV is spread through droplets in the air. (Unlike the coronavirus, it is also readily spread through surface transmission, and it can survive for many hours on hard surfaces.)
Another theory is that because pregnant women were not going out into the world as much during the pandemic, they didn’t come into contact with the virus themselves, which for them, would manifest basically as a cold. So they didn’t necessarily pass on antibodies during pregnancy, Ramilo said. “There are a lot of nuances that we need to understand,” he added.
Right now, it is simply too soon to say whether we’re in for another surge this fall and winter, just like it’s really too soon to say whether this upcoming flu season will be bad.
It’s also worth noting that RSV is not one of those viruses that you’re exposed to once and then don’t get again. “It’s not perfect immunity. It’s not like measles or chicken pox, where you get it once and you’re protected,” Ramilo said. “No. It’s a much more complex virus.”
So yes, your child could have RSV multiple times in one year. But if they’re older, it’ll likely just seem like a cold.
Avoiding crowded settings with babies is important this fall and winter
Fortunately, the protective measures that help prevent COVID-19 transmission can also minimize children’s risk of coming down with RSV: masking, social distance, and regular hand-washing.
Getting eligible children and adults vaccinated for COVID-19 can help too, so that children ― and particularly susceptible babies ― don’t have to cope with multiple viruses at once. There is not a vaccine for RSV, but Ramilo noted options are on the horizon, including vaccines that can be given to women during pregnancy so they pass antibodies along to their baby.
“We hope that in the next year and a half, two years, we will have vaccines and antibodies to prevent infections in young children,” he said.
In the meantime, parents and caregivers should be cautious about spending time in public spaces, and make sure that anyone who visits is symptom-free. If older siblings come home from school with a sniffle, you might not want them to cuddle with the baby, he said.
“If you take a 1-month-old baby to the mall, it’s possible that he gets exposed to someone with RSV, even if that person is not highly symptomatic,” Ramilo said. “Obviously, any visiting family member, any friend that has a runny nose should not kiss the baby.”
Experts are still learning about COVID-19. The information in this story is what was known or available as of publication, but guidance can change as scientists discover more about the virus. Please check the Centers for Disease Control and Prevention for the most updated recommendations.