A COVID-19 vaccination requirement for teachers and other staff members took effect in New York City's sprawling public school system Monday in a key test of the employee vaccination mandates now being rolled out across the country. Some people vocally opposed to vaccine mandates did protest Monday. Video posted to social media showed demonstrators marching in locations around the city. One video showed two men pulling down a COVID-testing tent on a busy street as protesters marched and chanted "no vaccine mandate." Mayor Bill de Blasio said 95% of the city's roughly 148,000 public school staffers had received at least one vaccine dose as of Monday morning, including 96% of teachers and 99% of principals. Some 43,000 doses have been administered since the mandate was announced Aug. 23, de Blasio said. The mayor had warned that unvaccinated school employees would be placed on unpaid leave and not be allowed to work this week. The city planned to bring in substitutes where needed. Schools Chancellor Meisha Ross Porter said she did not know exactly how many employees had declined the shots and been put on leave. Implementing the mandate smoothly will be a test for de Blasio, a Democrat who boasted of the city's record of keeping school buildings open during most of the last school year when other districts went to all-remote instruction. New York City is not offering a remote option this year. The vaccination mandate in the nation's largest school system does not include a test-out option, but does allow for medical and religious exemptions. It was supposed to go into effect last week but was delayed when a federal appeals court granted a temporary injunction. An appeals panel reversed that decision three days later and a request to the Supreme Court for an injunction was also denied. The 96% teacher vaccination rate cited by the mayor was slightly different from the 97% figure provided earlier Monday by United Federation of Teachers head Michael Mulgrew. Vaccination rates rose in every school job category after the mandate was announced. District Council 37 of the American Federation of State, County and Municipal Employees, which represents some 20,000 city Department of Education employees, said 93% of those workers had provided proof of at least one COVID-19 vaccine dose as of Sunday, up from 68% at the beginning of September. Under a deal worked out with the city, unvaccinated District Council 37 members who want to apply for a medical or religious exemption have until 5 p.m. Tuesday to do so, union officials said in a news release. New York City's million-plus-student public school system is one of the first in the nation to require inoculations for all staff members. A similar mandate is set to go into effect in Los Angeles on Oct. 15. Many students and parents support the vaccine mandate as the best way to keep schools open during the pandemic. Some people vocally opposed to vaccine mandates did protest Monday. Video posted to social media showed demonstrators marching in locations around the city, including outside a Department of Education building in Brooklyn, carrying signs saying things such as: "Resist Medical Tyranny!" Subscribe to our YouTube channel: https://bit.ly/2TwO8Gm Subscribe to our newest channel Quicktake Explained: https://bit.ly/3iERrup Bloomberg Quicktake brings you live global news and original shows spanning business, technology, politics and culture. Make sense of the stories changing your business and your world. To watch complete coverage on Bloomberg Quicktake 24/7, visit http://www.bloomberg.com/qt/live, or watch on Apple TV, Roku, Samsung Smart TV, Fire TV and Android TV on the Bloomberg app. Have a story to tell? Fill out this survey for a chance to have it featured on Bloomberg Quicktake: https://cor.us/surveys/27AF30 Connect with us on… YouTube: https://www.youtube.com/user/Bloomberg Breaking News on YouTube: https://www.youtube.com/c/BloombergQuickTakeNews Twitter: https://twitter.com/quicktake Facebook: https://www.facebook.com/quicktake Instagram: https://www.instagram.com/quicktake