WASHINGTON, Sept. 9 (Xinhua) -- The number of children testing positive for COVID-19 has surged 34 percent in Florida since schools across the southeastern U.S. state started to reopen for in-person teaching last month, the Washington Post reported on Wednesday.

As many as 10,513 children under age 18 have tested positive since schools started reopening in early August in the state, a hike of 34 percent, said the report, citing data from the Florida Department of Health. It's not clear how many of those children were in school or doing remote learning.

A number of schools and dozens of classrooms in the sunshine state have been temporarily shuttered because of coronavirus outbreaks, said the report, noting parents in many parts of the state don't know if coronavirus outbreaks are related to their own schools because the state ordered some counties to keep health data secret.

The state also left it up to districts to decide whether masks should be worn by students and staffers. Some require it, but many don't, said the report.

The state's Republican Governor Ron DeSantis has pushed aggressively for schools to offer in-person classes. Florida school districts began opening in early August, and by mid-month about half the state's 4,500 public schools had students in their buildings.

In a statement to Business Insider, the Florida Department of Health said on Wednesday it was working to develop a system to release information pertaining to COVID-19 infections in schools and in daycare facilities and would announce such in "the coming days and weeks."

The U.S. Centers for Disease Control and Prevention, as well as the World Health Organization, recommend a below 5-percent local COVID-19 positivity rate for the safe reopening of schools. Overall child positivity rate in Florida is 14.5 percent.

A total of 652,148 positive cases have been reported in the state since the pandemic began, with 12,269 deaths, as of Wednesday, according to state data. Case numbers have been steadily declining in Florida since July.