Monday was the first day teachers from Long Island who work in New York City must be vaccinated or risk being out of a job.

New York City Public Schools employs 148,000, and today all had to be vaccinated.

Over 90% did roll up their sleeves while about 10,000 did not and some peers wished there was another option for them.

"I think the testing option would be best to keep teachers in the classroom to supervise them. It's only hurting them in the long run,” says Doreen Pacino, West Islip.

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Unvaccinated teachers are on unpaid leave and cannot file for unemployment insurance.

However, Long Islanders who teach in New York City said their teachers union was able to secure their medical benefits.

The Department of Education says it has 9,000 vaccinated substitute teachers who will step in for any staffing shortages related to the mandate.

The largest public school system in the country is one of the first to issue a vaccine mandate on employees. Los Angeles will do something similar mid-month.

Medical and religious exemptions were granted.