GEOFF BENNETT: Now a look at an illness that's dangerous for babies, made worse by a shortage of drugs to treat it.

Amna is back with this report recorded earlier.

AMNA NAWAZ: Among children under the age of 5, RSV leads to as many as 80,000 hospitalizations and up to 300 deaths a year.

It's the number one cause of hospitalization for infants under a year-old.

Dr. Celine Gounder is an epidemiologist and senior fellow at KFF.

She also hosts the podcast "Epidemic: Eradicating Smallpox."

Celine, it's good to see you.

And let's just start with what it is that makes RSV so dangerous for young children in particular.

What does it do to their systems?

DR. CELINE GOUNDER, Infectious Disease and Public Health Specialist: Well, RSV, or really any viral respiratory infection, leads to inflammation in the airways, which can lead to mucus, could lead to thickening of the lining of the airways.

And between the two of those, you can get blockages of the airways, especially in young infants who have smaller airways to begin with.

AMNA NAWAZ: So there are approved drugs to treat it.

They're available as shots.

There is this nationwide shortage.

Is high demand the sole reason for that shortage?

And, if so, can we boost supply?

DR. CELINE GOUNDER: There is a new monoclonal antibody that's delivered as a shot.

Its brand name is Beyfortus that is new this season to help protect the youngest of infants.

The challenge is really manufacturing.

And based on what I'm being told by the CDC and pharmaceutical companies, the supply that we have available right now is the supply that we're going to have available for the season.

It simply just takes too long to manufacture more to have more available this season.

AMNA NAWAZ: So that shortage has now led the CDC to issue guidelines saying who should be prioritized.

Who are they saying should get those shots first?

And who does that leave out?

DR. CELINE GOUNDER: So, the youngest of infants, so those under the age of 6 months, as well as other infants who might have underlying medical conditions that predispose them to severe RSV.

And pediatricians can help parents figure that out.

There are alternatives.

So there's an older monoclonal antibody against RSV called Synagis that is also effective in protecting infants.

And that is being recommended for those between the ages of 8 and 19 months as an alternative.

And then there's a third option, which is to vaccinate pregnant women.

Those pregnant women will then produce antibodies to the RSV vaccine and pass those on through the placenta and through breast milk to protect their infants in that way.

AMNA NAWAZ: Celine, what should we understand about the cost of all of these treatments too?

Does that impact who is able to get it?

Is it covered by insurance?

DR. CELINE GOUNDER: Well, under the Affordable Care Act, insurance companies do not have to cover this until a year after the initial recommendation.

However, the big insurance companies are covering the RSV vaccine for pregnant women.

So, even already now, many pregnant women will have coverage.

It's also been challenging, however, to educate obstetricians about the need to vaccinate pregnant women against RSV to help reduce some of the issues we're having with shortages with the other options for infants, and also educating pharmacists who work in pharmacies that it is perfectly safe to be vaccinating pregnant women and, in fact, should be the norm.

AMNA NAWAZ: So a lot of parents are seeing the headlines about these shortages.

You have been hearing about looming tripledemics, right, coming in this next fall and winter season.

What is your advice to them on how they should proceed, especially if their child isn't eligible under those CDC guidelines?

DR. CELINE GOUNDER: Well, if your child is not eligible, do talk to your pediatrician about Synagis.

It is an alternative for the older infants.

And then it's the commonsense measures that we take to reduce the risk of infection, not just with RSV, but also with influenza, COVID and other respiratory infections.

So, if you're sick, stay away from other people.

If other people are sick, keep them away from your child, to the best that you can.

I know that can be challenging if a child is in day care, for example.

Masks do work.

So, if someone is sick and absolutely has to be around your child -- maybe they're a caregiver - - they should be wearing a mask to reduce the risk of transmission to your child.

Handwashing is also an important piece of this.

And then a way to reduce risk in general in various indoor spaces is open your windows, open doors if you can, or put in a HEPA air filtration unit to reduce the risk of transmission in that space.

AMNA NAWAZ: More broadly, when you look at this, the issue of demand being so high for a drug seems to go against the trend of vaccine hesitancy and, frankly, skepticism in science that we saw, particularly in the pandemic.

How do you look at that?

DR. CELINE GOUNDER: I think there's a few things at play here.

I think some parents really have seen whether it's their child or other young children get very sick from RSV, end up in the hospital from RSV.

And so it's very real for them.

I think another issue, though, is that COVID was politically polarizing, politicized in a way that RSV has not been.

And I think, between those two different factors, we're seeing a difference in demand and uptake.

AMNA NAWAZ: That is Dr. Celine Gounder, epidemiologist and senior fellow at KFF.

Dr. Gounder, always good to see you.

Thank you.

DR. CELINE GOUNDER: My pleasure.