Come mid-January, when infections from the Omicron variant are expected to be in full swing, patrons of the L.A. Phil will have to show proof of a booster shot to attend indoor performances at Walt Disney Concert Hall in Los Angeles.It will be the same for folks attending Los Angeles Master Chorale events at Disney Hall and Center Theatre Group performances at Ahmanson Theatre and Mark Taper Forum. The Music Center has expanded its overall vaccination policy to cover TMC Arts programming and lease events as well. The announcements were made Wednesday as the Omicron-variant surge in COVID-19 cases nationwide dominates the news. The University of Washington’s Institute for Health Metrics and Evaluation projects the Omicron surge will continue rising swiftly through December and into January, potentially peaking later next month or in early February.L.A. Phil will begin its booster rule on Jan. 18, while the Music Center rules go into effect Jan. 17. The Centers for Disease Control and Prevention and the Los Angeles County Department of Public Health have recommended that all people 16 and older get a booster shot when they become eligible.The Music Center noted one detail in a press release Wednesday: “In most cases, guests who are eligible for the booster but who have been unable to get it will be offered a one-month grace period.”L.A. Opera, which has no performances planned before March 2022, is evaluating its policies but has not announced any changes. On Dec. 9, CTG canceled “A Christmas Carol” moments before the show was to start after breakthrough coronavirus infections turned up in members of the company. Then came a few more short-term cancellations as CTG hoped to keep the show going. Finally, the group said Friday that it was canceling the rest of the run of “A Christmas Carol,” its first live production in 20 months, due to COVID-19 concerns. The pandemic has been devastating for CTG. The company was forced to lay off more than 50% of its staff, and remaining employees took significant pay cuts.CTG estimated in April that the historic closures across its three venues — the Ahmanson and the Mark Taper Forum downtown and the Kirk Douglas Theatre in Culver City — would result in the loss of $45 million to $55 million in box office revenue.