The move comes with word that 30 percent of New York City's healthcare workers are choosing not to get vaccinated.
One of those vaccination sites is the Gotham Health clinic, located not far from Yankee Stadium in the Melrose section of the Bronx.
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The clinic has been providing COVID-19 testing both to community members and to health care workers. Now it will start administering COVID vaccinations. It is operated by New York City Health and Hospitals.
Over the next few days and weeks, pop-up sites at school buildings and other locations in New York City will join the list of vaccination sites in the city.
Mayor Bill de Blasio is also moving forward with a plan to open five "Mass Vax" sites, each capable of handling thousands of people, in the coming weeks.
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"What you're going to see are a place where anyone can come any hour of the day, get a free vaccine, get it quickly," he said. "Sites will be, again, in all five boroughs, but we need State approval and support to move this effort. We have the capacity. We have the personnel. We need support."
That support is now in place. Wednesday morning, de Blasio announced the first of five "Mass Vax" sites will open Sunday along with three Department of Health vaccine hubs.
And the city is working to get 10,000 of the NYPD's 25,000 personnel vaccinated by Sunday as well.
The "Mass Vax" sites opening Sunday are located at Bathgate Industrial Park in Bronx and the Brooklyn Army Terminal Annex Building in Brooklyn.
Mega-site openings in the three remaining boroughs, Manhattan, Queens and Staten Island, have yet to be announced.
The plan calls for each of these sites to be open 24 hours a day, seven days a week. Officials say they will be able to deliver a combined 100,000 doses per week once they are all up and running.
In addition, the mayor announced the opening on Sunday for three smaller Department of Health vaccine hubs located at: Bushwick Educational Campus in Brooklyn; Hillcrest High School in Queens; and South Bronx Educational Campus in the Bronx.
The intention is to increase vaccination numbers that city and state officials agree have been disappointing.
Only about 33 percent of the 900,000 vaccine doses distributed in New York State have been administered. That number is lower in New York City.
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Mayor Bill de Blasio said he takes full responsibility.
But he also said Governor Andrew Cuomo's threat to take away any unused vaccine from city hospitals is not going to get them to speed this up.
The governor doubled down on that threat Tuesday.
"For those hospitals that have it already, use it or lose it, you won't get any more and you can be fined," Cuomo said. "Going forward, we just won't use those hospitals again."
One of the big critics of the slow rollout is the United Federation of Teachers.
The city's teachers union says it wants to organize its own administration of vaccines for teachers and school staff and to get that to happen sooner rather than later.
CHECK THE LIST of who is eligible for a vaccine in New York State
It's looking at the FDNY, which has already vaccinated 3400 members since it is administering the doses on its own and not using the hospital systems.
Currently, the vaccination process is still only open to health care workers, including outpatient practitioners and school nurses.
And despite the fact that 30 percent of these people have indicated they either don't want it or want to wait before receiving it, appointment schedules at the places where it is available today, are booked solid.
So if you are a health care worker looking to get your shot and you do not already have an appointment for today, officials say try for tomorrow.
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