According to the American Academy of Pediatrics report on Tuesday, the number of Covid-19 cases in children of all ages is reported 10 percent of all US cases, reports AP.

Most infected children have mild cases; hospitalisations and death rates are much lower than in adults.

The COVID-19 infection rate among adolescents aged between 12 and 17 is "approximately double" that of younger children, according to a new report by the US Centers for Disease Control and Prevention (CDC).

The report published on Monday analysed 277,285 confirmed COVID-19 cases in school-aged children in the US between March and mid-September.

Researchers found the average weekly incidence of COVID-19 in adolescents to be roughly 37 cases per 100,000 children, reports Xinhua

This is nearly double the rate in younger kids between the ages of five and 11, which reported an incidence of 19 cases per 100,000 children.

Underlying conditions were more common among school-aged children with severe outcomes related to COVID-19, said the report.

Among school-aged children with laboratory-confirmed COVID-19, 58 percent reported at least one symptom, 5 percent reported no symptoms, and information on symptoms was missing or unknown for 37 percent, according to the report.

The CDC found a total of 3,240 school-aged children with COVID-19 were hospitalized, including 404 who required ICU admission. Fifty-one school-aged children died of COVID-19.

"It is important for schools and communities to monitor multiple indicators of COVID-19 among school-aged children and layer prevention strategies to reduce COVID-19 disease risk for students, teachers, school staff, and families," said the report.

Dr Sally Goza, president of the American Academy of Pediatrics, said the rising numbers are a big concern and underscore the importance of masks, hand-washing, social distancing and other precautions.

“While children generally don’t get as sick with the coronavirus as adults, they are not immune and there is much to learn about how easily they can transmit it to others,’’ she said in a statement.

However, the CDC report did not indicate where or how the children became infected.

Just as cases in college students have been linked to partying and bars, school children may be contracting the virus at playdates, sleepovers, sports and other activities where precautions aren’t being taken, said Dr Leana Wen, a public health specialist at George Washington University.

“Understandably, there is quarantine fatigue,’’ Wen said. Many people have a sense that if schools are reopening, then other activities can resume too, “but actually the opposite is true."

Global school studies suggest in-person learning can be safe when transmission rates in the larger community are low, the CDC report said.

New York City, the nation's largest school district, with over 1 million students, resumed classroom learning Tuesday for elementary school children. Higher grades will resume on Thursday.

The CDC report said more than 277,000 children ages 5 to 17 were confirmed infected between March and September 19, with an increase in September after a peak and a decline over the summer.

The agency acknowledged that may be an underestimate, in part because testing is most often done on people with symptoms, and children with the coronavirus often have none.

The CDC reported 51 deaths in school-age kids, most in them ages 12 to 17. Less than two percent of infected children were hospitalized, and youngsters who are Black, Hispanic or have underlying conditions fared worse than white children.

The findings add to other data showing the pandemic is increasingly affecting younger age groups after initially hitting older Americans hard.

In a separate report Tuesday, the CDC said weekly COVID-19 cases among people ages 18 to 22 increased 55 percent nationally. The increases were greatest in the Northeast and Midwest and were not solely attributable to increased testing, the CDC said. About one-third of US cases are in adults 50 and older, while one-quarter are in 18-to-29-year-olds.

The AAP research is based on reports from public health departments in 49 states, New York City, Washington, DC, Puerto Rico and Guam. New York state doesn’t provide data by age. Most states count children's cases up to age 19, though a few use different age ranges.

As of September 24, the AAP counted nearly 625,000 youth cases, up to age 20, a 14 percent increase over the previous two weeks. Deaths totaled 109, well under one percent of all COVID-19 fatalities in the US.

As of Monday, the CDC counted over 435,000 cases in children from age zero through 17 and 93 deaths. The groups’ totals differ because they include different ages and time periods.

Dr. Yvonne Maldonado, head of the American Academy of Pediatrics’ infectious-diseases committee, said the big question is what will happen as schools that have started out with online learning go back to in-person classes.

“It really will depend on how well can you mask and distance in a school setting,” she said.

So far, 7 million Americans have been found infected with Covid-19 and 205,000 have died.

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