Soaring coronavirus infections in Hawaii don’t appear to be grounding airplanes dramatically amid the Christmas holiday travel rush locally as some airlines struggle with staffing- related flight cancellations nationally.

Two of the nation’s biggest air carriers — United and Delta — said the rising wave of COVID-19 cases fueled by the omicron variant have affected personnel and led to some flight cancellations on the heavy travel days of Christmas Eve and today.

Hawaii’s biggest carrier, Hawaiian Airlines, said it did not have an unusual number of flight cancellations for the holiday travel season. The airline said it canceled five flights Friday, all interisland. One neighbor island flight today also was canceled.

“We are keeping a close eye on our operation and will adjust to changing circumstances as warranted,” Kris Tanahara, a spokeswoman for the airline, said in an email. “We have been able to successfully reaccommodate our guests and thank them for their patience and understanding.”

At Hawaii’s busiest airport, flight-tracking firm FlightAware reported nine canceled Friday flights into or out of Daniel K. Inouye International Airport: four departures and five arrivals.

Of the nine cancellations, Delta had four, United had two and WestJet had two. Hawaiian was listed as having one, a flight from Maui to Oahu.

United and Hawaiian are two of the biggest carriers serving Hawaii, and the four canceled United flights represented 4% of its schedule locally, while the single Hawaiian cancellation was less than 1% of its daily service in Honolulu, according to FlightAware.

As of Friday afternoon three scheduled Christmas Day flights at the Honolulu airport had been canceled: one by Delta and two by United.

On Maui there were eight canceled Friday flights: four by Delta, two by United, one by Southwest and the Hawaiian flight to Oahu, FlightAware data showed. For today Delta had the only Maui flight cancellation reported by FlightAware.

Air travel in Hawaii has been relatively strong in recent months, with domestic flights driven by mainland tourism. FlightAware reported that the seven-day average of flight arrivals and departures in Honolulu through Thursday was 794, up from 465 in 2020 and 696 in 2019.

At the same time, Hawaii has been one of the states worst-hit by surging coronavirus infections. A single-day record of 1,828 new cases was set Friday after building over the past couple of weeks from around 100 per day at the beginning of December.

Of course, factors other than personnel are major causes of flight cancellations, including bad weather and mechanical issues. But fast- multiplying omicron cases have presented extra challenges in some instances.

United said in a statement that the nationwide spike in omicron cases this week has had a direct impact on its flight crews and other workers.

“As a result, we’ve unfortunately had to cancel some flights and are notifying impacted customers in advance of them coming to the airport,” the Chicago-based carrier said. “We’re sorry for the disruption and are working hard to rebook as many people as possible and get them on their way for the holidays.”

United added that it has on average 4,000 flights a day systemwide during the holiday season and that cancellations represent a small portion of flights.

FlightAware reported that 193, or 10%, of United’s flights to, from or within the U.S. were canceled Friday.

Delta said in a statement that a combination of issues, including but not limited to inclement weather in some parts of the country and the impact of the omicron variant, is driving cancellations expected throughout the weekend.

The Atlanta-based carrier said it canceled 158 of its nearly 3,100 flights Friday. FlightAware’s figure for canceled Friday Delta flights was 171, or 8%. Delta said upward of 150 canceled flights were expected both today and Sunday.

“We apologize to our customers for the delay in their holiday travel plans,” the company said. “Delta people are working together around the clock to reroute and substitute aircraft and crews to get customers where they need to be as quickly and as safely as possible.”