The number of children hospitalized with Covid-19 is soaring nationwide, especially as the highly transmissible omicron variant of the coronavirus spreads across the country.

According to an NBC News analysis, at least nine states have reported record numbers of Covid-related pediatric hospitalizations: Connecticut, Georgia, Illinois, Kentucky, Massachusetts, Maine, Missouri, Ohio and Pennsylvania, as well as Washington, D.C.

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Some of those children were found to be Covid-positive through routine testing if they had to be hospitalized for other, unrelated issues. But many have been hospitalized specifically because of complications from Covid-19.

The spike in hospitalizations frustrates pediatric infectious disease doctors on the front lines treating children sick with the coronavirus.

“It seems like people have tried to downplay the significance of the disease in children,” said Dr. Mark Kline, the physician-in-chief at Children’s Hospital New Orleans. “We’ve spent two years rebutting myths pertaining to Covid and children, that it’s ‘harmless’ for children. It’s not.”

As of Monday, Kline said, 14 children were sick enough with Covid-19 to be hospitalized at his facility, and three were in the intensive care unit.

The three children are under age 2. The youngest is just 8 weeks old.

At Texas Children’s Hospital in Houston, pediatric hospitalization numbers, at close to 70 patients, have surpassed the peak of patients during the surge of the delta variant in the summer, Dr. Jim Versalovic, a pathologist who is a co-leader of the Covid-19 Command Center, said at a news briefing Monday. More than 90 percent of the cases are due to the omicron variant.

“More children infected with omicron still translates into a big number of children who may need hospital-based care,” Versalovic said.

On Monday, the American Academy of Pediatrics reported a sharp rise in pediatric Covid-19 cases. At least 325,340 cases were reported during the week of Dec. 23, compared with 198,551 cases during the week of Dec. 16. While serious illness from Covid is still rare for younger children, the sheer number of new cases worries doctors.

As of Sunday, the number of pediatric Covid admissions had hit a new peak: 1,354 a day, based on a seven-day average, according to NBC News data.

And the number of kids who simply occupied hospital beds each day, even if they ultimately weren’t admitted to the hospital, reached a record average of 3,081 a day over the last seven-day period.

Kline co-authored a study, published last week by the Centers for Disease Control and Prevention, that analyzed 915 Covid cases among children and teenagers hospitalized at six medical centers in July and August.

More than three-quarters — 78 percent — were hospitalized because of complications of Covid-19. About half needed help breathing, and nearly a third were placed in intensive care.

A third of the 915 patients were otherwise healthy, without any underlying health problems that would have put them at greater risk.

“I think a lot of parents have been relying on the narrative that if you have a healthy child, it’s very unlikely that your child can get sick from Covid. That’s not true,” said Dr. Amy Edwards, a pediatric infectious disease expert at University Hospitals Rainbow Babies & Children’s Hospital in Cleveland.

“It is true that statistically speaking, your kid probably won’t have severe Covid, but statistics don’t matter when it’s your child who ends up getting sick,” she said.

Edwards said she and her colleagues have noted a “significant uptick” in the number of children admitted to the hospital recently with Covid-19, as well as an increase in the number of such children needing IV fluids, oxygen support and, in some cases, ventilation.

And doctors say that overwhelmingly, the vast majority of children hospitalized with Covid-19 are unvaccinated, because either they are too young to be eligible or their parents declined to get them vaccinated.

“We rarely see a vaccinated child in the hospital,” Kline said.

Kline conducted his research during the height of the delta variant’s spread last summer. Although some studies have suggested that the omicron variant may result in milder illness overall, Kline said the sheer number of omicron cases inevitably will lead to more hospitalizations.

“It’s a bit of wishful thinking to say, ‘Well, it’s mild,’ or ‘It’s going to be OK,’ but if there are 10 times as many cases, that still equates with a lot of hospitalizations and a lot of ICU admissions and, unfortunately, deaths,” he said.

Other pediatric infectious disease physicians, too, are concerned that the speed at which the omicron variant is spreading will increase the number of children sick enough to be hospitalized.

“I have never seen an infection sweep an entire country in a matter of a week or two,” said Dr. David Kimberlin, a co-director of the division of pediatric infectious diseases at the University of Alabama at Birmingham.

“The rate of cases in my portion of Alabama is like a rocket ship,” Kimberlin said. “It reflects how much virus is out there in the community. With that, we’re going to see increasing hospitalization numbers.”

Even if children are hospitalized for other reasons and test positive for Covid-19 during routine screenings, it doesn’t mean the impact is any less significant.

Dr. Chethan Sathya, a pediatric surgeon at Cohen Children’s Medical Center in New York, part of Northwell Health, said that “literally every child” whom he and his team operated on or treated otherwise over the weekend was Covid-positive. Even if their illnesses weren’t specific to the coronavirus, they stretched resources nevertheless.

A young patient rushed into the operating room because of a burst appendix, for example, must be put into an isolation room to recover from surgery if he or she is found to be Covid-positive.

“That just slows the whole system down and severely limits our ability to keep things moving,” Sathya said.

Although many pediatric Covid cases are mild enough to be cared for at home, doctors say there are some warning signs that a child isn’t improving and should be seen by a doctor.

Edwards, of UH Rainbow Babies & Children’s Hospital, said signs to watch for include:

• Trouble breathing.
• Dehydration.
• Persistent pain or pressure in the chest.

“As soon as you’re having trouble getting them to drink or their diapers are drying up or they’re not going to the bathroom as much and they look like they’re having a harder time breathing, that’s when we want to get them evaluated,” Edwards said.

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