Vehicles move past a man wearing a protective mask against COVID-19 as he waits for the bus in Karachi, Pakistan on December 11, 2020. (Photo by Akhtar Soomro/Reuters)

Medical staff in Belgrade, Serbia on February 5, 2021. Vaccination of employees in the city's social protection institutions has begun at the Belgrade Fair, who have expressed interest in receiving the Russian Sputnik V vaccine, and according to the city secretary for social protection Natasa Stanisavljevic, about 150 employees in those institutions will receive the vaccine today and tomorrow. (Photo by Zoran Zestic/Tanjug)

A woman holds her dogs during a snow flurry as temperatures dropped below freezing during the third coronavirus lockdown in London, Tuesday, February 9, 2021. (Photo by Kirsty Wigglesworth/AP Photo)

The Etam models perform on catwalk during ETAM Show at Flagship Hausmann near Opera in Paris, France on September 29, 2020. (Photo by J.P. Pariente/SIPA Press)

An armed police officer checks the documents of a cyclist at a checkpoint placed to implement a curfew in the country's capital amid rising coronavirus disease (COVID-19) cases, in Caloocan City, Metro Manila, Philippines, March 16, 2021. (Photo by Eloisa Lopez/Reuters)

A woman wearing a protective face mask carries her pet cat in a backpack as they wait to cross a street, amid the coronavirus disease (COVID-19) outbreak in Barcelona, Spain on April 9, 2021. (Photo by Nacho Doce/Reuters)

A traffic police officer directs traffic in Mohe City, northeast China's Heilongjiang Province, December 29, 2019. Temperatures in Mohe, “north pole” of China, often stand at below minus 40 degrees Celsius in winter mornings. Photo by Yang Siqi/Xinhua News Agency/Alamy Live News)

A man tries to extinguish an advertisement board set on fire during a demonstration of French labour union members and workers, as France faces its 38th consecutive day of strike against French government's pensions reform plans, in Paris, France on January 11, 2020. (Photo by Gonzalo Fuentes/Reuters)