• Attendees at the Times Square New Year's Eve celebration will have to wear masks, New York City Mayor Bill de Blasio announced Thursday.
• Social-distancing rules will limit the crowd to about 15,000 people, down from 58,000 in typical years.
• The measures are in addition to a vaccination requirement that was already in place for almost all attendees over the age of 5.

The Times Square New Year's Eve celebration will be scaled back, and attendees will have to wear masks, New York City Mayor Bill de Blasio announced Thursday.

A crowd limit of 15,000 people in viewing areas was also set to allow for some social distancing. Usually, there are 58,000 people allowed in viewing areas.

In addition, visitors will not be allowed in until 3 p.m., which is much later than previous years.

The measures are in addition to a vaccination requirement that was already in place for almost all attendees over the age of 5.

"There is a lot to celebrate and these additional safety measures will keep the fully vaccinated crowd safe and healthy as we ring in the new year," de Blasio said in a statement.

The announcement comes as New York City has seen Covid-19 cases surge, largely attributed to the omicron variant. Omicron is highly transmissible, but studies have shown it causes less serious illness, especially among the fully vaccinated.

On Dec. 19, the city reported a 15% Covid test-positivity rate, a five-percentage-point increase from just four days before. The World Health Organization estimates that omicron cases double every 1.5 to three days in places of dense population.

"We know that vaccination is the key and we know boosters are particularly effective against omicron. Our health-care leaders have been abundantly clear about that," the mayor told reporters at a news conference on Wednesday.

Previously, the Times Square Alliance, the group in charge of organizing the New Year's Eve ball drop and celebration, said it would require proof of full vaccination for almost all attendees over the age of 5. At the end of 2020, before vaccinations were widely available, the group also hosted a scaled-down event, with social distancing and masking for a significantly smaller audience than normal.

De Blasio told reporters at the news conference he expects omicron will peak in the city soon, but people will have to take extra precautions in the meantime to keep everyone safe.

"We focus, obviously, every day on the Covid crisis, on the challenge of omicron and how we overcome it, and I'm very confident the city will overcome it. In fact, it looks like it's going to be a very brief period – intense and challenging – but very brief, and we have a lot of tools to fight back," he said.

The city is ramping up testing and vaccinations over the holiday period, and on Christmas Eve thousands of at-home rapid tests are being distributed to safeguard public health.

Additionally, residents are being offered a $100 free gift if they get a Covid booster shot at a city-run site before Dec. 31.