Thousands of flights around the world have been canceled this week in a continuation of the travel chaos that unfolded over the holidays, with airlines blaming the spread of the omicron variant and adverse weather conditions for the disruptions.
By early Wednesday, more than 2,280 flights had been canceled globally for the day, with more than 740 flights within, to and from the United States called off, according to the flight tracking website FlightAware.
On Tuesday, there were more than 3,100 flights canceled, with 1,291 of those having expected to take off within, to and from the U.S.
U.S carriers Delta Air Lines and Alaska Airlines were among those to cancel flights this week, with the two collectively canceling hundreds of flights Tuesday and Wednesday.
Delta had said it expected to cancel more than 250 of 4,133 scheduled flights Tuesday alone, while Alaska canceled 170 flights across its network and warned of more cancellations and delays throughout the week.
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Both airlines have blamed weather and the spread of the Covid-19 omicron variant for the disruptions.
The cancellations come after a week of travel chaos over the holidays that saw airlines ax thousands of flights, with some blaming the spread of omicron among crew and other staff.
Delta said it was working to reroute and substitute some planes.
Meanwhile, Alaska said as it heads into Wednesday and Thursday, it is proactively thinning Seattle departures by around 20 percent to allow for additional time to de-ice aircraft in the midst of winter storms in the western U.S.
Snowy weather in the Pacific Northwest contributed to the cancellation of more than 110 flights scheduled to land at the Seattle-Tacoma International Airport on Monday alone, according to Reuters.
In the midst of the travel chaos, the Centers for Disease Control and Prevention said Tuesday that it was not considering recommending a Covid vaccine mandate for domestic flights after the possibility was suggested by Dr. Anthony Fauci, the nation’s top infectious disease expert.
“Right now, what we’re talking about is ways to get people vaccinated," CDC Director Dr. Rochelle Walensky said on National Public Radio. "Certainly domestic flights has been a topic of conversation, but that is not something we’re revisiting right now."
On Tuesday, the U.S. hit a record seven-day case average of 262,034 cases, surpassing a 252,776-case record set Jan. 11, according to an NBC News data analysis. The data can be skewed by days with anomalous data entries, which are common around the holiday period.
According to the CDC, omicron accounted for 58.6 percent of all Covid cases in the country in the week ending Dec. 25, while the delta variant accounted for 41.1 percent of cases.
Globally, the World Health Organization said Tuesday that the number of recorded Covid cases increased by 11 percent last week, compared with the previous week. The biggest increase unfolded in the Americas, according to the U.N. health body's data.