Pediatrician Dr. Mary King spends her Saturday night in the ICU, holding the triage phone at Seattle Children’s, answering call after call about small babies with the same symptoms. It's not Covid or the flu. It's RSV.

Typically, pediatricians see RSV cases surge from December through March, with February as the worst month. According to King, what's happening now is very different, with more children, of a variety of ages, contracting the virus much earlier in the year.

What is RSV?

RSV is short for respiratory syncytial virus, a common respiratory virus that spreads every year in winter. It's most common in small children, with the majority of kids having had the virus by their second birthday.

What are the symptoms of RSV?

In babies, it often causes increased lower airway secretions (lovely, we know). And because babies have small airways, they have more trouble managing those secretions, which can lead to wheezing, coughing, and respiratory distress. 

But it's not just the littlest ones. Adults are also at risk of contracting RSV. Their reaction to the infection is similar to that of a regular cold. However, it does pose a greater risk for older adults and those who are immunosuppressed, as they're more vulnerable to the virus.

What’s different about RSV this year?

Each time a child gets RSV, the symptoms become a little less severe due to the antibodies that build up from prior infections. It becomes more like a cold, instead of this huge illness that can lead to asthma or to some kids needing advanced respiratory support. 

Of course, due to Covid-19 and all the precautions we took to prevent its spread (masks, social distancing, you get the idea), a large number of kids between the ages of zero and three have never had RSV. There would typically be a lot of natural immunity within a group of children, where only about 5 percent would be vulnerable to RSV, King says. Now doctors are seeing maybe 75 percent of kids that have never come in contact with RSV, which is making it spread like wildfire. 

Why is RSV spreading so fast?

Aside from a lack of prior infections and natural immunity, the return to normal life after Covid is the biggest reason. Put another way, mask wearing, hand washing, and staying home while sick didn't just prevent Covid—it helped halt a host of other viral illnesses too. 

"I think there's a lot more mixing of events and big events happening," King says. "I think how we're approaching viral transmission now really is much more like it was pre-Covid. But now we have this really vulnerable cohort, which is very different. We've never seen this before.”  

Are our immune systems weaker post-pandemic?

“This example with RSV pretty clearly demonstrates to me that children didn't have the same antibody protection they did when they were getting this prior," King says. "In that way, I would say yes.” 

That's more about antibody levels than it is about the immune system as a whole, however. The severity of this year’s RSV cases is still unknown, but the number of children and the ages affected this year are unprecedented, King says.

How can you tell if you have RSV?

There is no outpatient test or swab-ready kit for RSV. The only formal way to test for it is through a respiratory panel done in a hospital. However, it's not as important to test for RSV as it is for Covid or influenza, situations where medications can help. Because there's no medication to give for RSV, it's not as crucial to know if you have it or not.

“I can say if you have a younger baby who has a cold, and they're having problems managing their airway secretions with a persistent cough, that is typically the story with RSV,” King says. “If your child has been immunized for influenza and for Covid, there's going to be a lower likelihood that those are going to be the viruses that are causing the problem.” 

While RSV can have similar symptoms to the common cold, it lasts around eight or nine days. Colds typically last only five to six days.

What are RSV treatments?

The key to treating an average case of RSV in a child is to get the fever under control so their breathing rate decreases and they can breathe better. King typically suggests lots of fluids and fever-reducing medications like Tylenol or ibuprofen (if your baby is older than six months). If your child is still having difficulty breathing, a snot sucker or suction bulb can help clear gunk out of the nasal passages as well.

How can we prevent the spread of RSV?

“If I had a family with a child less than two right now, I would be hunkering down like what we did with Covid,” King says. In addition to carefully considering group activities, she also encourages parents to stay in the know. Since there's a massive shortage of hospital resources across Washington, the best thing parents can do is learn how to treat fevers at home and the major warning signs they should look for before heading to the doctor’s office or emergency room. And, if you haven't already, get your kids their flu shots and Covid vaccines ASAP.