NEW YORK (CBSNewYork) — There was a major announcement Monday, just three weeks before the first day of school in New York City.

Mayor Bill de Blasio mandated vaccinations for all school teachers and staff.

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CBS2’s Thalia Perez spoke with parents about the decision.

Just about everyone Perez spoke to – moms, dads, kids, grandparents – all agree that this measure is a step in the right direction.

“I think that they suffered for a year and a half not being to be in school, and whatever we can do to get them back and keep them safe is really important to me,” said mother of two Lauren Karr.

WATCH: Mayor De Blasio’s Monday COVID Briefing 

Mandatory vaccinations for all New York City school teachers and employees was de Blasio’s announcement.

Karr says she welcomes the mandate because she believes it will be a much safer environment for her children, ages four and seven.

COVID VACCINE

”This vaccine mandate is on top of the multilayered measures we already have in place, which have made our schools some of the safest places to be during COVID. Universal mask usage, physical distancing, health screenings, testing, and improved ventilation,” said Schools Chancellor Meisha Porter.

Everyone from school principals, food service workers and custodians must get their first dose by Sept. 27.

”It is what it is. It’s necessary,” one man said.

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Weekly testing won’t be an acceptable alternative to the vaccine. The mayor says discussions with labor unions have already begun.

“Negotiations, we really do hope will yield a constructive, positive outcome quickly. If they don’t, yeah, things like arbitration are an available avenue,” de Blasio said.

Reaction came swiftly from the United Federation of Teachers.

“The city’s teachers have led the way on this issue, with the great majority already vaccinated.  While the city is asserting its legal authority to establish this mandate, there are many implementation details, including provisions for medical exceptions, that by law must be negotiated,” Michael Mulgrew, the union’s president, said in a statement.

CORONAVIRUS PANDEMIC

The mayor maintains he’s not worried about a staffing shortage.

“I know that there’s people that oppose some of the decisions but, thinking about greater good and my kids being part of that greater good, I want them to be protected, especially where they’re getting educated,” Karr said.

While officials said 63% of staff members are already vaccinated, the mandate still applies to 148,000 employees who must get their first dose by Sept. 27.

The announcement came the same day as the U.S. Food and Drug Administration granted the Pfizer vaccine full approval.

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CBS2’s Thalia Perez contributed to this report.

CBSNewYork Team