Global airline carriers have canceled more than 2,000 flights so far on Friday, the FlightAware website said, in an indication of how COVID-19 is affecting holiday travel.

The website showed that as of 8:20 a.m. Eastern Time (1320 GMT), 2,028 flights around the world had been scrapped.

FlightAware said there had been 448 cancellations within, into, or out of the United States so far on Friday.

United Airlines and Delta Air Lines (DAL.N) on Thursday said they had each canceled dozens of Christmas Eve flights, as the spreading coronavirus Omicron variant took a toll on its flight crews and other workers.