NEW YORK (CBSNewYork) Mayor Bill de Blasio’s Key to NYC program expanded to a new age group Tuesday.

At least one dose of a COVID vaccine is now required for children as young as 5 for things like indoor dining and entering entertainment venues.

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New signs greet crowds of people outside the Metropolitan Museum of Art, reminding people of the new rules, which left one mother, who was visiting from Tennessee, at ease.

“Keeping him safe is absolutely the biggest thing,” Erika Green said.

Her 8-year-old son is fully vaccinated, so she said she is all for the new mandate.

“Part of the reason we chose to come to New York is because of those vaccination requirements,” Green said.

Those 5 and older now need to show proof of one vaccination dose to dine indoors, go to the movies or other performances, and also for school activities, like sports, dance and band.

Then by Dec. 27, kids 12 and up will have to show proof of two doses.

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Most places, like the Children’s Museum of Manhattan on the Upper West Side, have been reminding families online of the new in-person rules.

“Certainly, it makes people like myself and family comfortable to come back,” local resident Heather Guardado said.

Jodi Cohen, like many area parents, said the new rules are easy to follow.

“I uploaded photos of their vaccination cards and have it on my phone,” Cohen said.

Her husband is now able to safely take their son to Tuesday night’s Knicks game.

“I’m excited because it’s my first time going to a sporting event since COVID started,” 11-year-old Zack Cohen said.

Watch Alice Gainer’s report — 

Many kids heading to Tuesday night’s performance of “The Lion King” on Broadway said they were glad to get the shot.

“Awesome. I’m glad I’m vaccinated because we can do so many more things,” 8-year-old Avery Hall told CBS2’s Dick Brennan.

“Not just to get to the show, but to do other stuff without the mask, and sometimes the mask can be, like, annoying, so sometimes you wanna just take it off,” 10-year-old Graham Dini said.

“I was actually prepared. I didn’t want to limit what she can and can’t do, so I just said, we’re getting vaccinated no matter what,” said Shari Jackson, who was attending the musical with her 10-year-old daughter, Shayla.

COVID VACCINE

CBS2’s Alice Gainer spoke to parents in Harlem, where the vaccination rate is just over 73%, which is lower than Manhattan and New York City’s overall rate.

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“I think it’s safer that way,” one person said.

“It’s a good rule, because right now a lot of people are dying, even kids,” Pedro Moreles added.

Moreles has two kids, ages 7 and 14.

“They were vaccinated about a month ago,” he said.

One woman who did not want to give her name said her 6-year-old daughter is not vaccinated.

“I’m gonna stay home. I’m not going out, I guess. I’m not gonna vaccinate her,” the woman said.

Back at the Metropolitan Museum of Art, Mirlaine Baron of Queens said she’ll only get her kids vaccinated if the schools mandate it. Otherwise, they’ll find somewhere else to hang out.

“There’s always Long Island. There’s always New Jersey. I just won’t be in the city,” Baron said.

CORONAVIRUS PANDEMIC

The vaccine mandate comes as infections among children are spiking, up 24% from just last week.

Health officials say the Omicron variant will soon dominate the United States due to its rapid growth.

“The main issue with this variant is that it’s far more transmissible than any other variant, meaning it’s very, very contagious, so it can spread from person to person quite easily,” immunologist Dr. Purvi Parikh said.

Despite Omicron spreading faster, medical experts say Omicron does not appear to be as life-threatening compared to other variants.

“Its kind of, like, mutating down so far from what we’re seeing and what we’re hearing because it is not as, for lack of better words, deadly as the Delta variant and as the initial variant we had a year and a half ago,” medical expert Dr. Alexander Salerno said.

Meanwhile, a hearing is scheduled Tuesday over the city’s vaccine mandate for municipal workers, impacting more than 160,000 people, including police officers, firefighters and sanitation workers. A judge will decide whether to issue a temporary restraining order for the mandate, which ordered city public employees to get their first shot by Oct. 29 or be forced to go on unpaid leave.

On the state level, Gov. Kathy Hochul is still pushing her new mask mandate for indoor public spaces that don’t require proof of vaccination.

“Protect individuals’ lives, particularly during what we are experiencing right now, which is a holiday surge,” Hochul said, adding hospitalizations are up 70% since Thanksgiving. “We anticipated a spike after Thanksgiving and it has arrived, and so this is an alarming jump state-wide.”

She might not want to have great expectations. Rockland County Executive Ed Day said Monday he doesn’t want to take employees away from vaccinations to police mask wearing.

“My objection was logistical,” he told CBS2. “How many calls I got today — I had a woman who went to Kohl’s department store and they almost threw her out of the store because she didn’t have a mask on. This is not the way to handle a crisis.”

The indoor mask mandate will be in effect until at least Jan. 15, when Hochul will reassess COVID conditions. If businesses don’t obey, they face a fine up to $1,000.

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CBS2’s Alice Gainer contributed to this report.

John Dias