The New York City vaccination mandate for private businesses went into effect on Dec. 27 as the surge in the Omicron variant intensified. The city’s expanded vaccine mandate, as part of Mayor Bill de Blasio’s Key to NYC program, is the strictest in the nation. It defines only individuals with at least two doses of a mRNA vaccine or one dose of the Johnson & Johnson to be “fully vaccinated.” De Blasio first announced the mandate expansion on Dec. 6, four days after NY State authorities reported the state’s first case of Omicron. According to de Blasio, NYC has seen tens of thousands of new cases each day, with more than 14,000 positive cases on Dec. 26 alone. The mayor said earlier this month that employees of 184,000 private businesses would need to submit proof of at least one COVID-19 vaccine shot. “We’re implementing the strongest vaccine mandate in the country,” said de Blasio …