A medical staff member rests next to a patient infected with Covid-19 in the intensive care unit of Lozenets Hospitalin Sofia on November 9, 2021. Bulgaria is among the countries with the highest number of deaths compared to its population. (Photo by Nikolay Doychinov/AFP Photo)

Revellers enjoying the pubs and clubs in Leeds despite concerns over Omicron on December 10, 2021. Festive revellers have hit the pubs and clubs across the UK tonight as Plan B rules come into force and fears grow over the spread of Omicron. (Photo by Nb press ltd)

Models are seen backstage ahead of the Hakan Akkaya x Cinderella Bridal Capsule Collection at Tersane Istanbul on November 30, 2021 in Istanbul, Turkey. (Photo by Ferda Demir/Getty Images for Hakan Akkaya)

Competitors climb in front of the Matterhorn mountain at the start of the 21st Glacier Patrol race in Stafel outside the ski resort of Zermatt, Switzerland, 18 April 2018. The Glacier Patrol (Patrouille des Glaciers in French), organized by the Swiss Army, takes place from April 17 to 21. Highly-experienced hiker-skiers trek for over 53km (3994m ascent and 4090m descent) along the Haute Route along the Swiss-Italian border from Zermatt to Verbier. (Photo by Valentin Flauraud/EPA/EFE)

Fifty years ago, as France exploded in mass protests, words scrawled on the walls of the Sorbonne summed up the revolutionary zeal of the time: “Run free, comrade, we’ve left the old world behind!”. Sexual liberation, artistic creativity and anti-capitalism were the order of the day. For those who were there, it was an unforgettable time. Here: A wounded student is transported by first-aid workers during riots on the Boulevard Saint-Michel, Paris, France on May 6, 1968. (Photo by Gökşin Sipahioğlu/SIPA Press)

A plane battling the Ferguson Fire passes the setting sun in unincorporated Mariposa County Calif., near Yosemite National Park on Sunday, July 15, 2018. (Photo by Noah Berger/AP Photo)

A woman takes a picture of a statue of a child wearing what appears to be a hazardous material suit in Fukushima, Japan on August 14, 2018. (Photo by Kwiyeon Ha/Reuters)

Vehicles pass through the heavy fog and air pollution that cover Skopje valley in the early morning, in Skopje, The Former Yugoslav Republic of Macedonia, 14 December 2017. According to media reports, Skopje is considered one of the most polluted cities in the world. (Photo by Georgi Licovski/EPA/EFE)