NEW YORK, Dec 6 (Reuters) - New York City expanded its array of COVID-19 mandates on Monday, setting vaccine requirements for children as young as 5 years old and for workers at all private-sector companies as the highly transmissible Omicron variant pushes into more U.S. states. The most-populous U.S. city set a Dec. 27 deadline for all 184,000 businesses within its limits to make their employees show proof they have been vaccinated, Mayor Bill de Blasio said.In addition, children 5 to 11 years old must get at least one dose by Dec. 14 and those 12 and older need to be fully vaccinated by Dec. 27 to enter restaurants and participate in extracurricular school activities, such as sports, band and dances. "Vaccination is the way out of this pandemic, and these are bold, first-in-the-nation measures to encourage New Yorkers to keep themselves and their communities safe,” de Blasio, who leaves office next month, said in a statement.De Blasio"s successor, Eric Adams, will evaluate the mandate and other strategies to combat the pandemic when he takes office in January, his spokesperson, Evan Thies, said. The mandate means that many young people, or their parents, will need to scramble to get a shot to keep eating out or participating in after-school activities. Only about 27% of New Yorkers ages 5 to 12 have taken at least one dose and just 15% are fully vaccinated, according to the city"s website. Vaccination mandates are a divisive issue nationally, and views among adults about having to vaccinate children differed in New York on Monday. Pia Fernandez-Vega, a resident of the borough of Queens, who was with her 14-year-old daughter, said: "We are a free country. If we are going to be mandated to have the vaccine, I think our freedom is being suppressed." Eunah Ainslie, also from Queens, said: "I think the mandate is great." Ainslie said her niece and nephew both got COVID-19 at their daycare centers and that she supports vaccines for children. For adult New Yorkers, vaccination rates are much higher. About 89% have received at least one vaccine dose, topping the national rate of 83.5% reported by the Centers for Disease Control and Prevention. Many companies, including several Wall Street banks headquartered in New York, such as Goldman Sachs Group Inc (GS.N), Morgan Stanley (MS.N) and Citigroup Inc (C.N), already require vaccines for anyone coming into their offices.A nationwide vaccine mandate issued earlier this year by President Joe Biden for companies with 100 workers or more was put on hold last month by a U.S. appeals court in New Orleans. read more An administration request to a U.S. appeals court in Cincinnati to reinstate the mandate is pending. read more NEW CASES ACCELERATING The new requirements, which the Greater New York Chamber of Commerce supports, come as new coronavirus infections are accelerating nationwide, especially in northern states, where colder weather is prompting social events to move indoors. Over the past week, the country has averaged more than 120,000 new infections a day, up 64% from the prior week, according to a Reuters tally. Deaths, which lag infections, have averaged 1,300 a day over the past seven days, up from a rate of 800 a week ago, according to Reuters data. Omicron, first detected last month in southern Africa, has spread around the globe and shows signs of being more contagious than the Delta variant, which is still dominant in the United States. Several dozen Omicron cases have been found in 18 out of 50 U.S. states: California, Colorado, Connecticut, Georgia, Hawaii, Maryland, Massachusetts, Louisiana, Minnesota, Mississippi, Missouri, Nebraska, New Jersey, New York, Pennsylvania, Utah, Washington and Wisconsin, according to a Reuters tally. Louisiana has also reported a probable Omicron case in a crew member on a cruise ship that disembarked in New Orleans over the weekend. At least 17 COVID-19 cases were detected on the ship, state health officials said. read more De Blasio, a Democrat and strong proponent of mandates who has issued them for several sets of municipal workers, expressed confidence his latest order would withstand legal scrutiny, as his previous orders did. Anne Dana, an attorney at the King & Spalding law firm, said the mayor"s private-sector mandate stands a better chance of going into effect than the Biden one because a similar city rule for restaurant, gyms and other private employers has already survived legal challenges. Some 94% of 378,000 city employees are vaccinated, up from 86% in late October, just before the city began enforcing its mandate for emergency responders, a spokesperson for the mayor said. A total of 1,339 workers are on unpaid leave and 12,200 have medical or religious exemption requests pending, he said. Reporting by Peter Szekely in New York and Barbara Goldberg in Maplewood, New Jersey; Additional reporting by Brendan O"Brien in Chicago, Elizabeth Dilts in New York and Susan Heavey in Washington; Editing by Lisa Shumaker and Peter Cooney