CNN  — 

Covid-19 infections have risen “exponentially” among children in the US since July, according to data published Monday by the American Academy of Pediatrics (AAP).

The group reported 243,373 new cases among kids over the past week. While this is a decline from last week, when 251,781 cases were reported, it’s about a 240% increase since early July, when kids accounted for 71,726 cases.

“After declining in early summer, child cases have increased exponentially with nearly 500,000 cases in the past two weeks,” AAP said in a statement.

The latest update comes as schools across the country are in full swing and experts have advised adults to get vaccinated to protect children under 12 who are not eligible for the vaccine.

As of Thursday, nearly 5.3 million children total have tested positive for Covid-19, AAP said, and children currently account for 29% of all cases reported nationwide.

Officials debate when child vaccines will be ready

As of Monday, 63% of the eligible population in the US – those 12 and older – are fully vaccinated, according to data from the US Centers for Disease Control and Prevention. Health experts and officials are aiming for the vast majority of the population to be inoculated.

President Joe Biden announced new vaccine requirements last week that were met with praise and criticism. The new requirements include a mandate for businesses with more than 100 employees to require vaccination or regular testing for employees.

Parents could have access to vaccines for children by Halloween, according to Dr. Scott Gottlieb, a board member at Pfizer and the former commissioner of the Food and Drug Administration.

He told CBS’ “Face the Nation” on Sunday that Pfizer is expected to have data on vaccinations for children ages 5-11 ready for the FDA by the end of September.

“The FDA says it will be a matter of weeks, not months, to make a determination if they’re going to authorize vaccines for kids between 5 to 11. I interpret that to be perhaps four weeks, maybe six weeks,” said Gottlieb.

CDC Director Dr. Rochelle Walensky said Monday, however, that the public health agency is working urgently on a Covid-19 vaccine for younger children she hopes could be ready by the end of the year.

In the meantime, the FDA cautioned parents not to race to vaccinate their children before approval from the agency.

“Children are not small adults – and issues that may be addressed in pediatric vaccine trials can include whether there is a need for different doses or different strength formulations of vaccines already used for adults,” the FDA said in a statement Friday.

Children are less likely to die from Covid-19

Children are far less likely than adults to suffer serious disease or to die from Covid-19. Among states that report hospitalizations by age, children make up 1.6% to 4% of patients who were hospitalized for Covid-19.

Among the states that report death by age, children accounted for no more than 0.27% of the deaths. Seven states have reported zero child deaths. As of Sunday, the CDC reported 523 deaths among people younger than 18 in the United States.

Pre-teens and teens have the lowest Covid-19 vaccination rates of any age group.

CNN’s Jacqueline Howard and Madeline Holcombe contributed to this report.