Children accounted for more than 20 percent of weekly COVID-19 cases by the end of August, according to a report by the American Academy of Pediatrics and the Children’s Hospital Association.

Kids made up 22.4 percent of cases last week, a higher number than the total average of child cases during the pandemic, 14.8 percent. There was also a 9 percent increase in the cumulative number of child cases from Aug. 12-Aug. 26.

The high number of cases comes as many children return to in-person classes at school, which has created a flood of concern.

Children under 12 are not currently eligible for the vaccine. Officials are looking to change that soon as the Food and Drug Administration is pressured to approve vaccines for children under 12.

COVID-19-related hospitalizations and deaths among children are not very common, but the American Academy of Pediatrics said more data is needed to study the long-term effects on children.

However, Centers for Disease Control and Prevention Director Rochelle Walensky said new studies being released Friday report that hospitalizations in children were four times higher in states with low vaccination rates in August, USA Today reported.

“Cases, emergency room visits and hospitalizations are much lower among children and communities with higher vaccination rates. Vaccination works,” Walensky said.