As schools reopen across the United States, the number of children hospitalized with Covid-19 has hit a record high, raising the possibility of closures in the fall due to Covid-19 outbreaks.

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How Covid-19 is affecting children

In the week ending in Aug. 12, more than 121,000 new Covid-19 cases were reported among children, accounting for about 18% of all reported cases, according to the American Academy of Pediatrics.

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In addition, 1,900 children were hospitalized with Covid-19 last week, a record high that represents about 2.4% of all hospitalized Covid-19 patients in the United States, according to data from HHS.

"There's more questions than answers," Andrew Badley, chair of the Mayo Clinic's Covid-19 research task force, said. "We do know comparing the delta variant to previous variants, people are sicker with the delta variant from the earlier variants and that includes children as well."

NIH Director Francis Collins said he's concerned about the rise in pediatric Covid-19 cases.

"I think traditionally people kind of considered, 'Well, you know, kids aren't going to get that sick with this,'" he said. "More than 400 children have died of Covid-19. And right now we have almost 2,000 kids in the hospital, many of them in ICU, some of them under the age of four."

Children are "very seriously at risk," Collins added. "And it's up to all of us to do everything we can to protect them, as well as we're trying to protect everybody else at the same time."

A study published Monday in JAMA Pediatrics looked at Covid-19 cases and positive coronavirus tests in Ontario, Canada, between June 1 and Dec. 31, 2020. It found that, while babies and toddlers were less likely than teenagers to bring the coronavirus into their homes, they were more likely to spread it to other members of their households.

Specifically, the study found that children between the ages of 14 and 17 made up 38% of all initial cases in a household, compared with 12% among children ages three and under. But children three and under were around 40% more likely to transmit the virus than those between the ages of 14 and 17.

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"The key takeaway for me is that it clearly shows that there's transmission from children occurring in the household," Zoe Hyde, an epidemiologist at the University of Western Australia, who was not involved in the study, said. "This means we urgently need to think about how we're going to protect schools when they reopen shortly."

Schools see Covid-19 outbreaks, could face closures in the fall

A number of school districts that have reopened have already seen Covid-19 outbreaks, with more than 10,000 students and staff in 14 states having been quarantined for exposure to the coronavirus since school reopened, according to local news reporting reviewed by the Washington Post.

The outbreaks coincide with the rampant spread of the highly contagious delta variant, and providers report seeing more children infected by the variant.

According to Michael Burke, interim superintendent of Palm Beach County in Florida, just two days after schools reopened, 440 students were sent home to quarantine.

Meanwhile, in Warren County, Kentucky, 95 Covid-19 cases have been reported, and more than 700 students and staff are in quarantine.

In Mississippi, at least 1,000 students and school staff have tested positive for the coronavirus, according to the state's department of health, with more than 4,400 students quarantining.

And about 1,200 students have quarantined since schools reopened in Arkansas, with more than 100 students and staff testing positive for the coronavirus.

Richard Besser, former acting CDC director and current CEO of the Robert Wood Johnson Foundation, said he doesn't believe that outbreaks will lead to society-wide shutdowns on the scale of last year. Still, he believes some school closures will happen.

"I think what we're going to see is schools closing when cases spread through schools," he said. "We're going to see more recommendations for use of masks."

Many schools throughout the United States have taken precautions to stem the spread of the coronavirus, including improving ventilation, spreading out children, and requiring masks, according to Mark Sawyer, an infectious disease specialist at Rady Children's Hospital.

However, in some states, including Oklahoma, Florida, and Arkansas, schools are forbidden from requiring masks.

"Wearing masks is an essential part of that equation," Sawyer argued. "Sending your kid to school without a mask really makes no sense. It's endorsed by the American Academy of Pediatrics, kids tolerate masks[,] and other than vaccination, it's the next best thing we can do to prevent spread." (Reed/Fernandez, Axios, 8/17; Choi, The Hill, 8/15; Vakil, The Hill, 8/15 [1]; Anthes, New York Times, 8/16; Peiser, Washington Post, 8/13; Vakil, The Hill, 8/15 [2])