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Why are COVID-19 cases in kids rising? It's mostly the adults around them

The pediatric cases are a direct reflection of what's happening in their surrounding communities, experts said.

The beginning of the school year is coinciding with new data showing a startling surge in children and teenagers diagnosed with COVID-19, as a new report finds that nearly half of all pediatric cases of the disease were diagnosed in a single month.

The spike does not indicate any sinister changes in the virus that would make children more susceptible. And there's no evidence that children are doing anything unusual that would account for such an increase.

Instead, the source appears to be rooted in the communities those children are living in.

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"The pediatric cases are in all of the same states that we know are surging with adults who have disease," said Dr. Jodie Dionne-Odom, an assistant professor of medicine in the division of infectious diseases at the University of Alabama at Birmingham.

Those states include Alabama, Arizona, California, Florida, Georgia, Illinois and Tennessee. Each of those seven states has tallied more than 15,000 COVID-19 cases among young people since the beginning of the pandemic.

Louisiana, Virginia and the Carolinas all reported at least 10,000 pediatric cases. The numbers may be slightly skewed, because states differ in how they define "child" in their COVID-19 reporting. Alabama's pediatric count, for example, includes anyone under age 25.

The increase was detailed in a joint report from the American Academy of Pediatrics and the Children's Hospital Association, published Monday.

Up to July 9, just over 200,000 cases of COVID-19 had been diagnosed in kids and young people in the U.S. in total. But from July 9 through Aug. 6, an additional 179,990 pediatric cases were reported — an increase of 90 percent in just four weeks.

"That got our attention," said Dr. Susan Coffin, a professor of pediatric infectious disease at Children's Hospital of Philadelphia and the University of Pennsylvania.

The summer spike came after an apparent lull in pediatric infections this past spring. Coffin suggested it was because in-person schooling had been halted, and children largely remained indoors, away from others in March and April. But the warmer months lead to an increase in gatherings.

"The array of activities that all of us are doing has expanded," Coffin said.

"We cannot simply assume that we don't have to worry about kids because they don't get infected," said Dr. Sean O'Leary, vice chair of the committee on infectious diseases for the American Academy of Pediatrics. "They absolutely do."

O'Leary noted that some of the rise seen in kids is likely reflective of more testing. But largely, the spike is related to a spike in overall infections. "In places where there are large increases in adult infections, there are also large increases in infections in children," he said.

Still, it appears children are largely spared the most dire health consequences of COVID-19.

Children accounted for 1.6 percent of all COVID-19 hospitalizations in the AAP report. But that percentage might not be nationally representative; just 20 states and New York City provide data on the ages of hospitalized patients.

Ninety young people have died with COVID-19, according to the report. Some of those had been diagnosed with an extremely rare but serious disease called multisystem inflammatory syndrome in children, or MIS-C, which is strongly believed to be linked to the coronavirus, according to the Centers for Disease Control and Prevention.

The agency has received reports of 570 confirmed cases of MIS-C, with additional cases under investigation.

Overall, children make up 9.1 percent of COVID-19 cases nationally.

The new report comes just as schools nationwide are opening their doors to students once again. While it does appear most infections among young people are mild, some children have underlying conditions, such as obesity, putting them at risk for complications.

What's more, teachers and other school staff may also be at increased risk if they have underlying conditions or are older.

Coffin stressed that the way to reopen schools safely is to control the spread of COVID-19 in the surrounding neighborhoods, even among households without children.

"Schools are complex microcosms of our larger community," Coffin said. "If we're good about wearing our masks in public, and limiting our gathering sizes, we will ultimately get to open our schools for in-person instruction."

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Other experts agreed.

"You have to keep your eye on the ball when you reopen," said Dr. Roberta DeBiasi, chief of Infectious Diseases at Children's National Hospital in Washington.

"We don't want parents to panic," DeBiasi said. "But we also don't want people to be too cavalier and say, 'I don't need to wear a mask or worry about playgroups because my child can't get infected.'"

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