Christmas baubles shaped as Santa Clauses wearing protective masks are pictured amid the coronavirus disease (COVID-19) pandemic in Eichenau, Germany, November 26, 2021. (Photo by Michaela Rehle/Reuters)

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)

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)

Houses near Taal Volcano's crater are seen buried in volcanic ash from the volcano's eruption on January 14, 2020 in Taal Volcano Island, Batangas province, Philippines. The Philippine Institute of Volcanology and Seismology raised the alert level to four out of five, warning that a hazardous eruption could take place anytime, as authorities have evacuated tens of thousands of people from the area. An estimated $10 million worth of crops and livestock have been damaged by the on-going eruption, according to the country's agriculture department. (Photo by Ezra Acayan/Getty Images)

Personal trainer Antonietta Orsini carries out an exercise class for her neighbours from her balcony while Italians cannot leave their homes due to the coronavirus disease (COVID-19) outbreak, in Rome, Italy, March 18, 2020. (Photo by Remo Casilli/Reuters)

A mobile phone showing the time at noon, is displayed for a photo in front of an almost empty road with low traffic, during the coronavirus disease (COVID-19) outbreak, in Wuhan, Hubei province, China, March 31, 2020. (Photo by Aly Song/Reuters)

A 9 year old girl receives digital lessons from the primary school teacher in Rotterdam, Netherlands on April 20, 2020, because the schools are closed due to the corona crisis staying at home. Many schools are putting together a homework package or using digital teaching methods, now that education has been closed for several weeks due to the corona virus. (Photo byRobin Utrecht/Rex Features/Shutterstock)