Missouri was one of three states that saw its number of confirmed cases of children with Covid-19 jump by more than 80% in late July, according to a national study, as the nation reported nearly 100,000 new cases among children over that span.

The swell of infections came as schools were working on plans to reopen schools, at least partially, for the 2020-2021 school year. But pressure is mounting for schools to open late and entirely online.

The report by the American Academy of Pediatrics and the Children’s Hospital Association accumulated publicly reported data that show children are making up an increasing percentage of the confirmed cases nationwide.

Between July 16 and July 30, there were 97,078 new child cases reported (241,904 to 338,982) which was a 40% increase, with over 7 out of 10 new child cases reported from states in the South and West, the report said.

But Missouri, along with Oklahoma and Alaska, showed the highest percentage increase over those two weeks according to the study — each increasing by some 80%.

The numbers are concerning as schools try to restart because recent research shows that, although children may usually exhibit milder symptoms of the virus, they can carry at least as much of the virus in their noses and throats as adults, and spread the virus to older relatives or their teachers.

Missouri now ranks 32nd in the nation in the cumulative number of child cases per 100,000 children with a rate of 340.8 per 100,000. The total of reported child cases in Missouri was 5,205 out of a total for all ages of 46,750.

Missouri ranks 23rd in the cumulative total of reported child Covid-19 cases.

Comparisons of child data between states are not exact. States differ in the age range designated as children. Missouri, like most states, uses an age range of 0-19 to designate children. Two states, Utah and Florida, use an age range of 1-14. One state, Alabama, counts children as 0-24.

What is unknown, the report notes, is the number of children infected but not tested and confirmed.