JetBlue to cancel over 1,200 flights into mid-January amid COVID-19 spike

JetBlue Airways announced on Thursday that it would cancel more than 1,200 flights stretching into mid-January amid a spike in coronavirus cases driven by the highly transmissible omicron variant.

The airline is canceling 1,280 flights, or roughly 10 percent of its bookings, until Jan. 13 in an effort "to get even further ahead of the expected increase in Omicron cases," executives wrote in a note to employees obtained by CNBC.

"This past week has been one of our most difficult operating periods during the pandemic," three JetBlue department leaders wrote in the Tuesday note, per CNBC. "The exponential growth in Omicron cases over just a couple of days is at a level that no one could reasonably prepare for."

Major airlines from Spirit to United continue to cancel flights as they struggle with staffing shortages as case numbers rise. More than 1,000 flights were canceled in the U.S. on Thursday, according to the flight-tracking website FlightAware.

Meanwhile, millions of people are still traveling through the holidays and into the new year. According to checkpoint data from the Transportation Security Administration, roughly 2 million travelers have been screened at U.S. airports each day since Christmas.

To address staffing shortages, JetBlue joined Delta Air Lines last week in urging the Centers for Disease Control and Prevention to drop the isolation period for infected or exposed individuals from 10 days to five days, which the agency did earlier this week.

Daily COVID-19 cases in the U.S. climbed to an all-time high of 446,072 on Monday, the CDC reported.