By CBSBoston.com Staff

BOSTON (CBS) — The holiday flight cancellations continued on Christmas Day.

United, Delta and JetBlue were among the airlines canceling another 900 flights on Saturday, CBS News reports, as a surge of Omicron COVID-19 cases caused staffing shortages. The cancellations come as the TSA confirms that air travel has returned to pre-pandemic levels.

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According to FlightAware, there were at least 80 cancellations at Logan Airport on Christmas.

“The nationwide spike in Omicron cases this week has had a direct impact on our flight crews and the people who run our operation,” a United Airlines spokesperson told CBS News in a statement. “As a result, we’ve unfortunately had to cancel some flights and are notifying impacted customers in advance of them coming to the airport.”

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Delta canceled more than 300 flights, according to FlightAware statistics.

“Delta teams have exhausted all options and resources — including rerouting and substitutions of aircraft and crews to cover scheduled flying,” the airline said in a statement Thursday.

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Health experts tell WBZ-TV that airline passengers are more likely to get COVID because of the Omicron variant. If people must travel, they are urged not to take their mask off during the flight at all if possible.

CBSBoston.com Staff