By CBSLA Staff

LOS ANGELES (CBSLA) — Amid the alarming rise in coronavirus cases as a result of the emergence of the Omicron variant, UCLA and UC Irvine returned to online learning Monday for the first two weeks of the winter quarter.

Royce Hall on the campus of the University of California, Los Angeles (UCLA) as UCLA lecturers and students celebrate after a strike was averted Wednesday morning. (Al Seib / Los Angeles Times via Getty Images).

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UCLA said that when classes begin on Jan. 3, they will be held remotely for the first two weeks. In-person instruction is expected to resume on Jan. 18.

While classes at UC Irvine will be remote, “the campus will remain fully operational, with the same staffing policies we have followed for the past few months,” UC Irvine Chancellor Howard Gillman wrote in a campus message on Dec. 21.

UC Riverside, UC Santa Barbara, UC Santa Cruz and UC San Diego also announced they would switch to remote classes for the first two weeks of the winter quarter. UC Davis announced it would switch to remote learning for just the first week of the quarter.

The change back to remote learning came after UC system president Michael Drake sent a letter to all school chancellors stating that all eligible students and staff will be required to receive a COVID-19 vaccine booster shot in order to return to UC campuses.

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UCLA said that all students returning to campus will have to provide proof of a booster by Jan. 18, and its faculty and staff by Jan. 31.

UCLA also said that its students will have to participate in a “robust” coronavirus testing program beginning no later than Jan. 9.

Drake also advised chancellors to put together “a plan for a January return to campus that mitigates public health impacts, responds to the unique circumstances facing your campus and maintains our teaching and research operations.”

The UC system has 10 campuses.

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(© Copyright 2021 CBS Broadcasting Inc. All Rights Reserved. City News Service contributed to this report.)