A health worker shows an empty syringe after inoculating a woman with AstraZeneca's COVID-19 vaccine during the first day of a nationwide three-day vaccination drive at a school in Quezon city, Philippines on Monday, November 29, 2021. There has been no reported infection so far caused by the new variant in the Philippines, a Southeast Asian pandemic hotspot where COVID-19 cases have considerably dropped to below 1,000 each day in recent days, but the emergence of the Omicron variant has set off a new alarm. (Photo by Aaron Favila/AP Photo)

Dancer of the Berlin State Ballet (Staatsballett Berlin) wear face masks as they perform during the dress rehearsal of Don Quixote in a production choreographed by Victor Ullate, amid the coronavirus disease (COVID-19) pandemic at Deutsche Oper opera house in Berlin, Germany, December 1, 2021. (Photo by Fabrizio Bensch/Reuters)

Kite-surfers practice in a water reservoir at the shores of the Mediterranean sea close to the southern Israeli kibbutz of Ziqim during stormy weather, on December 20, 2021. (Photo by Menahem Kahana/AFP Photo)

A Palestinian man dressed as Santa Claus gestures as he rides a camel in Jerusalem's Old City during Christmas celebrations, on December 23, 2021. (Photo by Ahmad Gharabli/AFP Photo)

Revellers make the most of Boxing Day in Liverpool city centre, United Kingdom on Sunday, December 26, 2021. Boxing Day is a holiday celebrated after Christmas Day, occurring on the second day of Christmastide. (Photo by London News Pictures)

Revellers take part in the Els Enfarinats festival, in the town of Ibi near Alicante, Spain, Tuesday December 28, 2021. For about 200-years the inhabitants of Ibi annually celebrate with a battle using flour, eggs and firecrackers, outside the city town hall. (Photo by Alberto Saiz/AP Photo)

Participants lay down on a street covered by coloured powder during the annual Bangkok Color Run in Bangkok, Thailand April 1, 2017. (Photo by Athit Perawongmetha/Reuters)

A dog, at the behest of his owner, rides a skatebaord on April 3, 2017 in Berlin, Germany. The dog's owner, who looked like he might be homeless, coaxed the dog to ride the skatebaord and asked passersby who stopped to watch for money. (Photo by Sean Gallup/Getty Images)