The acting health secretary said in about 6 weeks, the number of COVID-19 cases in kids has jumped nearly 300%.

HARRISBURG, Pa. (AP/KDKA) — Masks will be required in all Pennsylvania K-12 schools, Gov. Tom Wolf announced Tuesday, reversing course amid a statewide COVID-19 resurgence that is filling hospital beds just as students return to class.

The Department of Health order will take effect Tuesday, Sept. 7 — the day after Labor Day — and will require students, teachers and staff to wear masks when inside. They’ll also be required inside early learning programs and child care providers. The order will not apply to student-athletes while they’re playing.

READ MORE: Republican Leaders Reject Gov. Tom Wolf’s Call For Mandating Masks In Schools

“My office has received an outpouring of messages from parents asking the administration to protect all children by requiring masks in schools,” said Wolf. “The science is clear. The Delta variant is highly transmissible and dangerous to the unvaccinated, many of whom are children too young to receive the vaccine. Requiring masks in schools will keep our students safer and in the classroom, where we all want them to be.”

The Democratic governor took action after the Republican leaders of the House and Senate rejected his request to pass legislation requiring masks in classrooms. GOP lawmakers acknowledged that coronavirus cases are again surging across the state but insisted that local leaders were best positioned to respond to the pandemic.

WATCH: KDKA’s Pam Surano Reports

“I’m relieved, on one hand, because it really takes the pressure off of me as a school leader to make a decision I’m not really qualified to make,” said McKeesport Superintendent Dr. Mark Holtzman.

Less than a month ago, Wolf had ruled out a statewide mask mandate for schools after requiring them last year. But the highly contagious delta variant of the coronavirus has changed the administration’s calculus about what is needed to keep students in class.

“I preferred for local school boards to make this decision. Unfortunately, an aggressive nationwide campaign is spreading misinformation about mask-wearing and pressuring and intimidating school districts to reject mask policies that will keep kids safe and in school,” said Wolf. “As we see cases among children increase in Pennsylvania and throughout the country, this is especially dangerous and challenging as we seek to keep kids in school and maintain a safe and healthy learning environment.”

Beam said the reality of the pandemic now is “extremely different” than it was a month ago, pointing to rising case counts, hospitalizations and deaths. She says the number of cases among Pennsylvania kids between 0-17 years old rose by 277% between mid-July and Aug. 28.

Pennsylvania is now averaging more than 3,200 new, confirmed infections daily — 20 times the number of cases it was reporting on a typical day in early July. More than 1,700 people are hospitalized with COVID-19, up sevenfold since last month. Deaths have doubled in two weeks to about 20 per day.

READ MORE: Gov. Tom Wolf Asks Lawmakers To Mandate Masks In Classrooms

Beam points to the more contagious delta variant, saying it accounts for more than 98% of the state’s COVID-19 cases.

Pennsylvania’s two statewide teachers unions had urged K-12 schools to require masks in school buildings, citing delta’s threat. The U.S. Centers for Disease Control and Prevention recommends masks in schools for students, staff and teachers.

“Kids want to be back in school. And how do we keep them in? Right now, rules around health and safety are a mask on the face,” said Baldwin-Whitehall School District Superintendent Randy Lutz.

But masking is a highly contentious issue, and school board meetings have been the scene of heated debate as parents argue for and against.

In some districts like North Allegheny, Peters Township and Canon-McMillan, parents have taken the battle over masks to court.

Some schools have reimposed mask mandates on their own after starting out the year without them.

In May, Pennsylvania voters narrowly approved a statewide referendum that curbed a governor’s emergency powers. The constitutional amendments were proposed by Republican lawmakers angry over Wolf’s handling of the COVID-19 outbreak, including his orders shuttering businesses, sending students home for online schooling and ordering masks worn outside the home.

But Wolf — who largely had lifted his orders before the referendum — has maintained that the referendum did not limit his authority to issue orders designed to prevent COVID-19 from spreading, such as shutdowns or masking restrictions. Those rest on separate public health law, his administration has said. The Wolf administration says the mandatory masking order for schools was signed under Beam’s authority provided by the Disease Prevention and Control Law.

MORE NEWS: Schools Should Require Masks, Pennsylvania Teachers Union Says

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