How widespread is COVID-19 in children? A look at the latest data as schools reopen

As schools across the country start to reopen, recent data shows that COVID-19 infection is on the rise in children.

The American Academy of Pediatrics, in collaboration with the Children's Hospital Association, each week surveys all publicly available data from U.S. states on child COVID-19 cases.

According to its most-recent report, as of July 30, there were 338,982 total child COVID-19 cases reported since the onset of the pandemic. That represents 8.8% of all COVID-19 cases.

In 25 states, 10% or more of reported cases were in children, the report found. The highest percentages were in Wyoming, Tennessee and New Mexico, with over 15%. New Jersey and New York City, meanwhile, had the lowest, with 3% or less.

The overall rate was 447 cases per 100,000 children in the population, the report found. Seventeen states and the District of Columbia reported more than 500 cases per 100,000 children, according to the report. Arizona had the highest rate, surpassing 1,000, while Hawaii had the lowest, under 100.

Overall, COVID-19 cases are on the rise in children: From July 16 to July 30, there was a 40% increase in child cases, the report found. The total number of cases, percentage of total cases and rate of cases in children are also the highest they've been since the AAP and CHA's first report, which examined COVID-19 data as of April 16.

However, COVID-19-related hospitalizations and deaths in children are "uncommon," and severe illness is "rare," according to the AAP. Based on data from 43 states and New York City, children made up less than 1% of all COVID-19 deaths. Twenty states have reported zero deaths in children, and these made up as much as 3.7% of total reported COVID-19 hospitalizations in 20 states and New York City, the report found.

The professional association noted that "states should continue to provide detailed reports on COVID-19 cases, testing, hospitalizations and mortality by age so that the effects of COVID-19 on children's health can continue to be documented and monitored."

The latest study looked at demographic data from 49 states, plus New York City, Washington, D.C., Puerto Rico and Guam. New York did not provide age distribution for state-wide cases, the study noted. Age ranges varied from 0 to 14 to 0 to 24, depending on the state.

Latest CDC data

The Centers for Disease Control and Prevention also tracks COVID-19 data by demographic, based on reports from U.S. states, U.S. territories, New York City and D.C.

As of Aug. 9, children under the age of 18 accounted for 7.4% of reported COVID-19 cases and less than 1% of reported COVID-19 deaths, according to the CDC. As of Aug. 1, there were 616 reported COVID-19-associated hospitalizations in patients under 18 -- nearly 1.4% of total hospitalizations.

Most children with COVID-19 are asymptomatic or have mild symptoms, according to the CDC.

The CDC is also tracking what they call the multisystem inflammatory syndrome in children (MIS-C), a rare but severe condition that was reported several weeks after the onset of COVID-19 in children and adolescents.

The condition may cause shock, gastrointestinal symptoms, cardiac involvement and elevated inflammatory markers, according to the CDC.

As of Aug. 6, 570 MIS-C patients and 10 deaths have been reported from 40 states, D.C. and New York City, the CDC found. The average age for kids affected was 8 years old.

What to know about the coronavirus:

• How it started and how to protect yourself: Coronavirus explained
• What to do if you have symptoms: Coronavirus symptoms
• Tracking the spread in the U.S. and worldwide: Coronavirus map

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