Black and Hispanic children are disproportionately affected by COVID-19, according to two Centers for Disease Control and Prevention reports published Friday.
The CDC reports come just days after President Donald Trump told Fox News that children are "almost immune" to the coronavirus, an assertion proven to be untrue.
As of July 31, more than 338,000 children in the United States have been diagnosed with COVID-19, according to the American Academy of Pediatrics. That represents about 8 percent of the nearly 5 million cases reported so far in the U.S.
And pediatric cases appear to be rising. One of the CDC reports released Friday found that between March 21 and July 25, "weekly hospitalization rates steadily increased among children." Overall, Black and Hispanic children were most likely to require hospitalization.
About a third of those children were sick enough to be admitted into a hospital's intensive care unit. That's equal to the proportion of adults with COVID-19 who have required critical care, even though children in general are less likely to be as severely impacted by the virus as adults.
Forty-two percent of the 208 children in the CDC analysis had at least one underlying condition, usually obesity.
"Childhood obesity affects almost 1 in 5 U.S. children," the CDC authors wrote, "and is more prevalent in Black and Hispanic children."
It's unclear how obesity might affect the severity of COVID-19 outcomes, but the link has also been noted among adults with the virus.
"There's something about obesity that causes an underlying inflammatory state that we don't understand that much about," said Dr. Josh Denson, a pulmonary medicine and critical care physician at the Tulane Medical Center in New Orleans. Denson treats severely ill adult COVID-19 patients, and has recently published research on the link between the coronavirus and obesity in the African American population.
Also Friday, the National Institutes of Health announced it's launching a project called PreVAIL kIds that aims to identify which children might be most at risk for COVID-19 complications.
The study will analyze, in part, biomarkers found in blood samples taken from children with COVID-19, so scientists can determine how the virus impacts young people, as well as which ones might be most at risk.
"This is a new virus, and it's really critical to understand what it does to children long term," said Dr. Bill Kapogiannis, a senior medical officer with the NIH's National Institute of Child Health and Human Development.
The main goal of the project is to learn more about one of the most severe COVID-19 complications among kids: multisystem inflammatory syndrome, or MIS-C.
William Lantry, 10, of Pittsburgh, who was diagnosed with MIS-C in June had no idea he'd even been infected with the coronavirus.
His mother, Tacia Brentley, noticed he seemed a "little off," and had a sore neck. When his temperature soared past 104 degrees Fahrenheit, she took him to the emergency room.
"It didn't really feel like I had been sick," William said, but added that the day his mother took him to the hospital, his neck pain stretched from his head down his shoulder, and he was vomiting.
Physicians suspected the child had meningitis, and put him on oxygen. Later tests revealed he'd had the coronavirus.
William has since recovered, but remains on steroids to help his breathing.
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The second report published Friday by the CDC looked specifically at MIS-C.
Out of 570 such cases, 364 — nearly 64 percent — needed to be put in intensive care. Ten young patients died, the CDC reported.
Symptoms of MIS-C included fever, rash, eye infections, gastrointestinal problems and heart damage, and tended to show up nearly a month after being exposed to the coronavirus that causes COVID-19.
Dr. Kevin Friedman, a pediatric cardiologist at Boston Children's Hospital, said he and his colleagues have treated nearly 40 such cases.
Symptoms of MIS-C are "occurring somewhere between three and six weeks after acute COVID exposure or infection," he told NBC News. "In some cases, children don't even know they had COVID and had no acute symptoms."
There is no specific treatment for MIS-C or less severe cases of COVID-19 in children. Friedman said doctors are treating patients with anti-inflammatories and supportive care to boost their heart and lung function.
As with severe COVID-19 cases, racial and ethnic disparities are common for MIS-C, as well. About 60 percent of children with MIS-C in Massachusetts, Friedman estimated, have been Black or Hispanic.
Indeed, the CDC report found that overall across the country, MIS-C tended to be more prevalent —73.6 percent — in racial minorities.
Brentley wants parents to remain alert for unusual symptoms in children. "The very second you see something that isn't normal, just go. Go straight to the hospital."