More than 60 flights were canceled at Heathrow Airport due to Omicron infections causing staff shortages.
British Airways, Lufthansa and several others have been forced to cancel flights due to crew members or ground staff positively testing or isolating with further cancellations and delays possible today (Monday).
Personnel who did not test positive have been in contact with the infected, but are then forced to isolate themselves.
Hundreds of flights around the world have been affected by increasing numbers of Omicron infections with routes in the US badly affected. The leading US airlines Delta, United and JetBlue were also among the most affected, according to flight data.
JetBlue canceled 10 percent of its flights on Sunday. Delta canceled five percent and United axed four percent according to FlightAware.
United warned earlier that a spike in Omicron cases “had a direct impact on our flight crew and the people carrying out our operation”, adding that it had contact with affected passengers before arriving at the airport.
American Airlines spokesman Derek Walls said the crystal cancellations stemmed from virus-related sick calls.
Airlines around the world canceled more than 4,500 flights over the Christmas weekend as the Omicron variant caused greater uncertainty and misery for holidaymakers.
Carriers worldwide scrapped at least 2,401 flights on Christmas Eve, according to a running number on the flight tracking website FlightAware, with 1,779 Christmas Day flights worldwide.
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