<span style="color: #222222;">Commercial airlines around the world cancelled more than 4,000 flights over the Christmas weekend, as a wave of COVID-19 infections driven by the Omicron variant created greater uncertainty and misery for holiday travelers. Airline carriers globally scrapped at least 2,314 flights on Friday, which fell on Christmas Eve.<br />''<br />''According to a running tally on the flight-tracking website FlightAware.com., another 1,404 Christmas Day flights were called off worldwide, along with 340 more scheduled for Sunday.<br />''<br />''Commercial air traffic within the US and into or out of the country accounted for roughly a fourth of all the canceled flights over the weekend.<br />''<br />''COVID-19 infections have surged in the US in recent days due to the highly transmissible variant Omicron. The average number of new COVID cases has risen 45% to 179,000 per day over the past week. New York reported more than 44,000 newly confirmed infections on Friday alone, shattering that state's daily record.<br />''<br />''In Britain, many industries and transport networks were struggling with staff shortages as sick workers self-isolated, while hospitals have warned of the risk of an impact on patient safety.<br />''<br />''According to data released on Thursday by the Office for National Statistics, one in 20 Londoners had COVID-19 last week, a figure that could rise to one in 10 by early next week.<br />''<br />''While recent research suggests Omicron produces milder illness, and a lower rate of hospitalizations, than previous variants of COVID-19, health officials have maintained a cautious note about the outlook.</span><br />