Nine percent of New York City’s municipal workforce remains unvaccinated following a Friday deadline to demonstrate proof of receiving at least Covid shot, officials said.

However, the percentage of city workers with at least one dose rose considerably as the deadline loomed.

Opposition to vaccine mandates fueled by rightwing politicians and media figures led to protests in New York this week. But on Saturday night, authorities said 91% of city workers had received at least one dose, up from 83% on Friday and 76% on Thursday.

Workers who did not abide by the requirement were still due to be placed on unpaid leave from Monday, potentially spurring staffing shortages in the police, fire, emergency medical services and sanitation departments.

The New York police department vaccination rate stood at 84%, officials said. Asked about the plan for dealing with a potential staff shortfall, an NYPD spokesman said in an email: “We will be prepared for any changes in personnel due to the mandate.”

City data indicated that 78% of fire department workers, and 79% of sanitation department workers, had received at least one dose as of Saturday.

Those agencies also said they were preparing for staffing shortfalls.

Fire officials said they were prepared to close up to 20% of fire companies and see 20% fewer ambulances in operation.

The department planned to change schedules, cancel vacations and seek out non-fire department EMS providers.

The fire commissioner, Daniel Nigro, slammed some firefighters who took paid sick leave in advance of the vaccine deadline.

“The department has not closed any firehouses,” Nigro said. “Irresponsible bogus sick leave by some of our members is creating a danger for New Yorkers and their fellow firefighters. They need to return to work or risk the consequences of their actions.”

The New York City mayor, Bill de Blasio, recently said the sanitation department would implement 12-hour shifts rather than the normal eight-hour shifts, and start working on Sundays so garbage did not accumulate amid staffing shortages.

The Associated Press contributed to this report.