More than 61,000 children in the U.S. were diagnosed with COVID-19 last week — more than in any other week during the pandemic, the American Academy of Pediatrics and the Children's Hospital Association reported Monday.
In all, 853,635 children have been diagnosed with the virus this year, representing 11.1% of all U.S. cases. The percentage of pediatric cases has risen steadily since mid-April, when children accounted for just 2% of COVID-19 cases in the country.
"This is a stark reminder of the impact this pandemic is having on everyone — including our children and adolescents," Dr. Sally Goza, president of the American Academy of Pediatrics, said in a news release. The organization updates the number of children with COVID-19 weekly, using state health department data.
The organization said it believes the true number of children with COVID-19 is higher because the illness tends to be mild in kids and because they may not always be tested.
Children accounted for less than 3.5% of current COVID-19 hospitalizations, the report found. As of Thursday, 121 children had died.
The tally doesn't include a 13-year-old boy who died over the weekend in Missouri, less than two weeks after he last attended class. In a statement provided by the boy's school district, his family urged people to wear masks, wash their hands frequently and follow social distancing guidelines.
"Covid-19 is real and they want to remind students and parents to take these precautions in and outside of school," the statement read.
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The American Academy of Pediatrics report found that in October, the greatest increases of pediatric COVID-19 case numbers — increases of 25% or more — occurred mostly in Western states: Alaska, Colorado, Idaho, Montana, New Mexico and Utah. The Dakotas, Kentucky, Michigan and Wisconsin also reported greater rises among children.
"It just keeps going from horrible to even worse," said Dr. Greg Demuri, a pediatric infectious disease specialist at UW Health in Madison, Wisconsin. "There doesn't seem to be any end in sight."
Demuri said UW Health is now seeing new pediatric COVID-19 hospitalizations on a daily basis. Total cases in the state have risen 88% in the past two weeks, according to NBC News figures.
"We are entering a heightened wave of infections around the country," Dr. Yvonne Maldonado, chair of the AAP Committee on Infectious Diseases, said in a statement. "We would encourage family holiday gatherings to be avoided if possible, especially if there are high risk individuals in the household."
Goza said, "On every measure — new infections, hospitalizations, and deaths — the U.S. is headed in the wrong direction."
A version of this story originally appeared on NBCNews.com.