PHILADELPHIA (CBS) — Pennsylvania’s two statewide teachers unions on Wednesday urged K-12 schools to require masks in school buildings, a measure that state officials are encouraging but have not mandated as students prepare to return to class.

The Pennsylvania State Education Association cited the threat of the highly contagious delta variant of the coronavirus, which is spiking infections and hospitalizations across the state and nationally, including among children.

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“Masking up is essential to keeping in-person learning going all year,” said Rich Askey, PSEA president. “If we’re going to be able to keep our schools open for in-person instruction all year, we need to make the right decisions now.”

AFT Pennsylvania, the state affiliate of the American Federation of Teachers, also called on schools to require universal masking.

“It is a good time to remember something we learned over a year ago: my mask protects you; your mask protects me. To even consider not implementing a universal mask mandate in schools is quite frankly outrageous. Layered mitigation works,” said Arthur Steinberg, president of AFT Pennsylvania.

The U.S. Centers for Disease Control and Prevention recommends masks in schools for students, staff and teachers.

But masking has become a highly contentious and politicized issue, with heated discussions taking place at the local level as school boards decide what their policy will be as schools reopen for the fall. Some Pennsylvania districts said they will require masks, while others have decided to make them optional.

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Joseph Roy, superintendent of Bethlehem Area School District, announced Wednesday that masks will be required in school buildings, citing the exponential spread of the virus in surrounding Northampton County since early July.

Roy said the district’s health experts have determined that the ongoing surge means “there’s no more latitude” on mandated, universal masking. The measure will be in place at least through the end of September.

“I’m not happy that that’s where we are, but I have to do my duty to protect our kids and our staff and our community and it’s clearly the right thing to do,” he said.

The state Health Department is urging school districts to follow federal guidance and require masks for all students, teachers and staff, regardless of vaccination status, but Alison Beam, the acting health secretary, said this week that a statewide mandate is not under discussion.

“The administration continues to strongly encourage school districts to adopt CDC guidance, which recommends universal masking for K-12 schools,” Maggi Barton, a Health Department spokesperson, said Wednesday.

Statewide, confirmed infections have nearly doubled over the past two weeks to an average of 2,000 per day. Hospitalizations are up sharply and deaths have started to rise again, too. More than 60 of Pennsylvania’s 67 counties are considered to have substantial or high rates of community transmission, according to the CDC.

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