New York, Jan 1 (IANS): Travel disruptions are slated to persist in 2022, as heavy holiday traffic in air and on ground overlapped with a spike in coronavirus cases in the US, and airlines, train companies and even their regulators grapple with staff unavailability as a result of the pandemic's ever more contagious variants of Omicron and Delta.

The US set a new record high of over 640,000 daily Covid-19 cases on Friday, according to latest data of Johns Hopkins University. A total of 647,067 new cases and 1,409 new deaths were reported across the nation on Friday. The single-day increase of cases has set a new record since the onset of the pandemic in the country, Xinhua news agency reported.

Heading into the New Year's weekend, when return flights will produce another crest in air travel, airlines have been canceling more than 1,000 flights a day to, from or within the US.

"Carriers and their employees say the latest chapter of the pandemic, the Omicron variant, has cut deeply into the ability to staff flights, even though a vast majority of crew members are vaccinated," reported New York Times on Thursday.

JetBlue has been one of the airlines hardest hit, canceling 17 per cent of its flights on Thursday, according to the air travel data site FlightAware.

The carrier said on Wednesday that it would cut about 1,280 flights through mid-January, citing the rise in virus cases in the Northeast, where its operations and crews are concentrated.

As many as 10 million people may fly from Thursday through Monday, according to Transportation Security Administration estimates. For months, airlines have been preparing reserves of workers for the holiday rush, but "those measures were inadequate in a fast-changing situation, and many passengers were frustrated," said the report.

Out of the ongoing difficulty of staff shortage, Spirit Airlines flight attendants are receiving triple pay on any work through January 4, their union said, as the budget carrier scrambles to keep its schedules intact after US airlines were hammered by a week of mass cancellations.

"All flight attendants, regardless of how you have obtained your pairing, will be receiving 200 per cent pay for any pairing that touches December 28 through January 4," the Association of Flight Attendants-CWA said in a statement. The union represented about 4,000 flights attendants at Spirit Airlines, according to the carrier's latest annual filing.

Spirit Airlines is an American ultra-low-cost carrier headquartered in Miramar, Florida, in the Miami metropolitan area. Spirit operates scheduled flights throughout the US and in the Caribbean and Latin America. Spirit was the fourth largest passenger carrier in North America as of 2020, as well as the largest ultra-low-cost carrier in North America.

To make things worse, the Federal Aviation Administration (FAA) said on Friday that an "increased number" of its own employees are testing positive for the Covid-19 infection, which could force it to implement health and cleaning procedures that reduce the number of flights the system can handle.

"To maintain safety, traffic volume at some facilities could be reduced, which might result in delays during busy periods," the FAA said, adding that airlines canceled more than 11,000 flights since Christmas Eve, including more than 1,000 already scrapped from Saturday and Sunday schedules, but none of those were the result of FAA issues.

Meanwhile, CNN quoted the Transportation Security Administration (TSA) as saying on Thursday that it has "adequate staff to cover flight schedules and passenger volumes."

The TSA expects 10 million more people to pass through airport screening between now and the end of Monday.

Amtrak, a passenger railroad service that provides medium and long-distance inter-city rail service in the contiguous US and to nine cities in Canada, said on Thursday that it will reduce its schedule between New Year's Eve and January 6 as it battles bad weather in some parts of the country and a surge in coronavirus cases among its employees.

Nearly two dozen trains on both its Northeast Corridor and long-distance routes will be affected. The reductions are about 1.5 per cent of Amtrak's trains that were scheduled for the week.

"Amtrak regrets any inconvenience," the railroad said in a statement.

"We are continuing to monitor changing conditions and will make any further adjustments as required."

"The trimmed train schedule mirrors thousands of canceled airline flights since Christmas Eve and disruptions to local transit services as the fast-spreading Omicron variant drives case counts to their highest levels of the pandemic," reported The Washington Post.

Earlier on Tuesday, multiple lines on New Jersey Transit had to cancel trains as the transit agency dealt with what it called "crew availability" difficulties, while New York City Transit said it had to suspend three lines for the same reason.

"Like everyone in New York, we've been affected by the Covid surge. We're running as much train service as we can with the operators we have

available," said the Metropolitan Transportation Authority (MTA), a public benefit corporation responsible for public transportation in the New York City metropolitan area of the US state of New York.

The W line was suspended all of Wednesday, which had an effect on riders, many of whom said that their commutes were impacted. Its suspension continued on Thursday and the B and Z services were also cut. The MTA suggested straphangers use the Q trains in Brooklyn and D trains in Manhattan and Bronx.