NEW YORK (CBSNewYork) — The highly contagious Delta variant has driven New York City’s COVID-19 cases to its highest total since May.

And health experts say those most vulnerable are the unvaccinated, CBS2’s Dick Brennan reported Thursday.

New York, New Jersey, and Connecticut are all in the top 10 for vaccinations. Still, the area is seeing an increase in hospitalizations, rising in New York from 340 to 483 in the space of a week, CBS2’s Tony Aiello reported.

“We’re seeing a small uptick, but that does not mean that a week from now, or two weeks from now, there won’t be a greater uptick,” said Michael Israel, CEO of Westchester Medical Center.

In the city, Mayor Bill de Blasio has been showing his frustration with the lagging vaccinations. This week, he mandated either vaccines or testing for city hospital workers.

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But the big question now is will he extend the mandate to other agencies that are lagging? For example, only 43% of the NYPD is vaccinated.

“I am issuing a FOMO alert, unless you want to spend the rest of your life saying, ‘Oh my God, I missed it,'” de Blasio said.

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The mayor is pulling out out all the stops to push people to get the shots, playing on the fear of missing out on concerts and events the city is planning. Simply, he said, you have to have the vaccine.

“You should get to New York City in the month of August, where amazing things will be happening during homecoming week,” de Blasio said.

COVID VACCINE

But it appears the mayor is ready to use the-carrot-and-the-stick approach if he has to.

“I mean, this is crazy. Get vaccinated. That’s just … it’s time for a very aggressive, assertive approach,” he said.

Just what does that mean? This week he mandated city hospital and health clinic workers get vaccinated or tested once a week, but on Thursday he was asked if he would widen the mandate to other agencies like, for example, the NYPD.

“We’ll be talking about the next steps in the days ahead,” de Blasio said, adding, “Now I say to the NYPD and every other agency, everyone’s gotta do better. Everyone’s gotta do better. We gotta go farther. We’re gonna look at a variety of ways to do that.”

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The mayor is showing his exasperation with first responders who say they don’t necessarily need the vaccine because they have had COVID and have the antibodies already.

“This is in the category of give me a bleeping break. When did everyone get a medical degree? Yeah, I’m sick of everyone armchair saying that they know more than the doctors. With all due respect, it’s a free country. People have an entitlement to their opinion, but give me a break. Listen to the doctors who have been protecting you and saving the lives of your family and your community,” de Blasio said.

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Some 70% of adult New Yorkers have gotten at least one dose of the vaccine, but some neighborhoods are still below 50%, and that’s where the city is hoping to target.

CBS2’s Tony Aiello contributed to this report.

Dick Brennan