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GABE GUTIERREZ: Inside Connecticut Children's Hospital in Hartford, doctors and nurses are sounding the alarm.
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UNIDENTIFIED REPORTER: In cases of RSV. Now, that's a common respiratory illness that's left some children in need of hospitalization. So the surge...
AYESHA RASCOE, HOST:
It's not just in the news. Everywhere you turn these days, there's RSV, a cold, flu, COVID.
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ANGIE BEAVIN: And it's driving student absences nationwide. So far, at least 59 school districts in Kentucky have closed.
RASCOE: Leaving parents scrambling to find childcare and even to find children's Tylenol and Motrin and other pain relievers among a surge in demand. So why are so many children getting sick all at the same time from so many different illnesses? Researchers are looking at the idea that for many infectious diseases, a second or third infection tends to be milder than the first time you get sick. And since so many children weren't exposed to some common viruses during the pandemic because of school closures, masking and social distancing, they're catching this stuff now for the first time. It's been shorthanded as immunity debt. And as Keren Landman writes, it's an easily misunderstood concept. Dr. Landman is a senior health and science reporter for Vox, and she joins us now. Welcome to the show.
KEREN LANDMAN: Thanks so much for having me, Ayesha. Great to be here.
RASCOE: Can you explain what is meant by immunity debt, and how it relates to our so-called post-pandemic world or post...
LANDMAN: Mid-pandemic...
RASCOE: Yeah.
LANDMAN: ...Hopefully near end of pandemic. The term itself was coined in August of 2021, so a little over a year ago, by a group of French pediatric infectious disease experts. And what they were trying to do was basically imagine what the trends would look like across a whole range of common childhood infections, ranging from RSV to flu to chickenpox to bacterial meningitis and beyond once we lifted preventive measures against COVID really broadly, like once schools opened up and people were no longer masking broadly and, you know, all these other things that we put in place had kind of stopped.
RASCOE: So basically, a large number of people and children are vulnerable to the disease. Is that what it is?
LANDMAN: That's exactly right. And, you know, to understand why that happens, you have to understand, you know, what immunity means and where immunity comes from. Babies get their immunity mostly while they're in the womb. So whatever their pregnant parent passes on to them during pregnancy, whether because they get infected during pregnancy or because they get vaccinated during pregnancy, those antibodies are really what help protect newborn babies through the first few months of their lives. Now, older children also get protected from infections by being either vaccinated against them or by being exposed to them. And, you know, over those - these last three years, a lot of adults, including pregnant adults, really have not had a lot of exposures to colds either.
So now those babies born in 2020 who never got exposed, babies born in 2021, whose parents did not get exposed and who themselves did not get exposed during any kind of daycare experiences over the next year, and, you know, babies born since then, there's just been less immunity, both from exposures of those babies to other kids and less immunity passed on to them from their parents during pregnancy. So all of that adds up to a lot of susceptible kids now going back to daycare and getting sick.
RASCOE: Some people would listen to this and say, well, doesn't this mean that it's better for people to go out and get sick and then they would be less vulnerable to getting these really intense illnesses? Is that the case?
LANDMAN: That actually is not. And let me explain why. The risk that babies face, especially from RSV, but also the risks that younger children face from respiratory illnesses and from other illnesses is more severe than the risk that older children face, even toddlers. And a lot of that, especially with respiratory illnesses, is related to the size of their air tubes. They're just a lot smaller. And so when they get clogged, it has the potential to completely shut off that tube, whereas for an - even a slightly older kid, you know, that airway might just get a little narrower, but can still - you can still move air through it.
So preventing kids, even delaying infection in babies really matters because it can make the difference between a kid not being able to move air at all and needing to go on a ventilator to help them or, you know, moving air less well than usually, but well enough that they can be managed with medicines or, you know, at home. You know, I think as we learn more also about post-viral syndromes like long COVID, we're starting to understand that the post-viral period can be full of problems.
RASCOE: But ultimately, I guess, what are some of the larger steps that as a society people might be able to take to be safer?
LANDMAN: Masks will help protect individual people. So if that is something that you want to do, then by all means you can feel like you're protecting yourself somewhat, certainly from respiratory infections, when you mask up. Washing your hands also really does help. RSV is transmitted more than some other respiratory viruses by touch. So washing your hands before and after contact with other folks, before you eat, before you touch your face. Where you can, open windows, get airflow into a room. Air purifiers, you know, with high-quality HEPA air filtration also really make a big difference. Where you can get vaccinated against some of these infections, do - so flu and COVID, obviously. So get vaccinated against those infections.
RASCOE: Dr. Keren Landman is Vox's senior health and science reporter. Thank you so much for joining us.
LANDMAN: Thank you so much for having me, Ayesha. It was a real pleasure to be here. Transcript provided by NPR, Copyright NPR.
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