New York City teachers and other school staff members are required to be at least partially vaccinated against COVID-19 as of Monday as the controversial mandate for the largest public school district in the country goes into effect. Ninety-five percent of all full-time schools staff met that requirement by the time the city's roughly million public school students were in the chairs. That number includes 99% of public school principals and 96% of teachers, the mayor said. #NEWS4NOW #NBC4NY