By Natasha Brown

PHILADELPHIA (CBS) — COVID-19 vaccinations are underway for Philadelphia public school teachers. The district says it’s another layer of safety as they reopen schools.

The Children’s Hospital of Philadelphia has begun the process of vaccinating school district teachers and staff members.

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“Yesterday, 500 people throughout the course of the day and we’re on track to vaccinate 500 more today,” said Dr. Ron Keren of Children’s Hospital of Philadelphia.

The vaccination plan will be rolled out in three phases beginning with teachers and staff already in classroom settings, pre-k to second-grade teachers heading back to the classroom, then phasing in the remaining teachers who want to get the vaccine.

“Getting vaccinated is a personal choice, yet we’re hopeful as many members of our staff as possible will take advantage of this opportunity as we believe the science that supports vaccinations as another layer of safety,” Superintendent Dr. William Hite said.

The Philadelphia School District is moving ahead with plans to bring pre-k to second-grade students into hybrid learning beginning on March 1.

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The return has been delayed several times due to teachers citing safety concerns inside school buildings. A mediator is now facilitating a safe reopening plan that both sides can agree on.

“This is a fluid process, so the more important thing is that we are still engaged in these conversations and looking for ways to solve this problem,” Dr. Hite said.

The vaccination process is adding one more layer of safety with six school sites that will be added as inoculation centers next week.

Children’s Hospital will be in charge of vaccinations at those locations, with thousands of teachers and staff from public, parochial and charter schools are expected to be vaccinated per day in the coming weeks.

“We’ve invited 25,000 teachers to sign up for vaccine appointment and we’re going to invite about another 10,000. By week two, we’ll have the capacity to immunize 9,000 employees a week,” said Dr. Keren.

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Vaccinations will be by appointment only and rapid tests will be provided for in-school use.