What to Know About the RSV Surge

Photo: Jill Lehmann Photography/Getty Images

In recent weeks, pediatric units across the country have been overrun by an uptick in RSV, or respiratory syncytial virus, a contagious infection affecting the lungs and airways. The seasonal illness is common: Dr. Jennifer Lighter, a pediatric infectious-disease expert and hospital epidemiologist at NYU Langone Health, tells the Cut that, pre-pandemic, everyone normally got it by the age of 2. RSV typically consists of mild, cold-like symptoms that resolve in one to two weeks, but it can be serious for babies under one and lead to more severe complications, including bronchitis and pneumonia.

While RSV normally peaks in the winter, this season’s surge has come early. The New York Times reports that children are falling seriously ill from RSV at higher rates than normal, and preliminary CDC estimates indicate that nearly one in 500 babies under the age of 6 months has been hospitalized with the virus since October. Though the reason for the timing of the surge is unclear, many experts believe the social-distancing measures of the last few years have prevented kids from building up their immune systems against the virus. Now that temperatures are dropping and kids have returned to school largely mask-free, seasonal illness is back in full swing. It’s not just RSV: Dr. Christopher Strother, director of pediatric emergency medicine at Mount Sinai, says he’s seen increases in respiratory illnesses across the board. “There’s lots of colds and fevers, and also a fair bit of rhinovirus, enterovirus, a bit of COVID, and some flu cases going around. We’re at mid-winter volume right now, and it’s sort of one virus on top of the next.”

Here’s what to know about the RSV surge.

What is RSV ?

RSV is a common respiratory virus that infects the lungs and the breathing passageways. Most cases are mild, especially among older children and adults, but the infection can be more serious in infants, who have small airways that can be blocked from even slight amounts of mucus. Children with asthma are also at-risk for more severe complications, as are those with sensitive lungs and chronic lung disease, as well as premature babies. “They’re smaller to start with and don’t have a lot of reserve,” says Dr. Strother. “If you put mucus and inflammation in their lungs, they get distressed more easily and get sicker than bigger, healthier kids.”

With so many respiratory illnesses going around, how do you know if you or your child are suffering from RSV? Dr. Strother warns that the symptoms are “similar” to the flu and COVID, but of the three, RSV is the most taxing on the lungs. “It’s going to look like the classic flu,” he says, “Usually you’ll see lots of mucus, a bit of congestion, and a junky, mucus-y cough.” Even children who don’t have asthma can develop wheezing or noisy breathing, and older children are likely to experience sore throats, headaches, and body aches. In adults, the virus usually presents as an upper respiratory illness; per Dr. Lighter, you’re likely to be reinfected with it several times throughout your lifetime in the form of a mild cold. That said, elderly and significantly immune-compromised adults, for whom there’s a risk of the virus moving down the airways and causing lower respiratory infection, should exercise extra caution.

Why is RSV worse this season?

Even though children are getting sicker with RSV than they have in previous seasons, Dr. Lighter says there’s no evidence that this year’s virus is a more severe strain, or even that it’s more transmissible. Rather, it may be that with masking and social distancing, fewer kids were getting sick in the past few years — so for many young children, this season is their first no-holds-barred brush with the virus. “There were decreased incidents in the last two years and it picked up a little in 2021,” says Dr. Lighter. “Now that it’s back, cohorts from 2020, 2021 and 2022 who weren’t infected will be.” Dr. Strother adds that older children haven’t had the chance to build immunity through repeat exposure. “If you have the flu this year, you’re less likely to get it next year, though it’s not a guarantee,” he explains. “It’s the same with RSV. Some kids get it and the next year they won’t pick it up when they’re exposed, because they have immunity left over, or they get it and don’t get quite as sick.”

What can you do to prevent transmission?

Make sure you and your children are vaccinated for the flu and COVID to soften any potential RSV infection. RSV is mostly transmitted through touch, so encourage children to make a habit of washing their hands thoroughly. Caregivers should also wash their hands, especially before caring for at-risk infants, and be careful about exposing their children if they’re unwell. “If you’re sick, be careful being around your baby,” says Dr. Lighter. “All the rules we learned from COVID, they apply to RSV.”

How is RSV treated?

Most RSV cases are mild and typically resolve within a week or two. For at-home treatment, Dr. Strother advises parents to keep their kids well hydrated and comfortable. Tylenol or Motrin can be administered for fever. “There’s no treatment to get over it faster, unfortunately. It’s really just about getting them through it so their bodies can heal,” he says.

If your child is experiencing excessive trouble breathing or dehydration, reach out to your pediatrician. “If kids are breathing fast, or using extra muscles to breathe, those things should bring you to the doctor,” Dr. Strother says.  Hospital treatment is largely supportive: “If kids need extra oxygen, we give it to them. We’ll give them fluids if they’re dehydrated, and if they’re struggling to breathe, we’ll give them masks to make it a little easier.”

Is there a vaccine?

While premature infants commonly receive preventative antibody treatments, like palivizumab, during RSV season, there’s currently no vaccine for older children. That could change soon: Pfizer recently concluded late-stage trials of a vaccine that Dr. Lighter is “optimistic” about. “It was given to pregnant women, and proved safe and effective,” she says. Pfizer will soon apply to the FDA for approval, but even assuming it’s approved, it isn’t likely to be available until next season.

What to Know About the RSV Surge