Ellen MacRae a student from Edinburgh University take a lateral flow antigen test at a test centre which is also open to students in Edinburgh Napier University, Queen Margaret University and SRUC on December 1, 2020 in Edinburgh, Scotland. The programme is running in partnership between the University of Edinburgh and other Scottish universities, the Scottish Government and NHS Test and Protect, supporting students leaving their term-time accommodation to travel home at the end of term for the winter break. (Photo by Jeff J. Mitchell/Getty Images)

A seagull files over a man sitting at a coffee shop backdropped by the Bosporus Strait in Istanbul, Tuesday, November 17, 2020. (Photo by Emrah Gurel/AP Photo)

Young women wearing facemasks and traditional costumes of Song dynasty and Tang dynasty are seated on a bench in a park next to the East Lake in Wuhan, in China’s central Hubei province on May 17, 2020. The Guardian picture desk has chosen on December 17, 2020, the AFP photojournalist Hector Retamal as “Agency Photographer of the Year 2020” for his coverage of the novel coronavirus Covid-19 pandemic in Wuhan, China. (Photo by Hector Retamal/AFP Photo)

Residents wearing masks to protect from the coronavirus cross a junction in Beijing on Wednesday, January 20, 2021. (Photo by Ng Han Guan/AP Photo)

An injured person reacts during a protest against the new government of President Manuel Merino, in San Martin de Lima square, in Lima, Peru, 14 November 2020. Merino took office on 10 November amid a controversial constitutional process after the dismissal of former President Martin Vizcarra for “moral incapacity” by Peruvian Congress. (Photo by Aldair Mejia/EPA/EFE)

Demonstrators celebrate with green headscarves - the symbol of abortion rights activists – outside the Argentine Congress in Buenos Aires on December 11, 2020, after legislators passed a bill to legalize abortion. (Photo by Ronaldo Schemidt/AFP Photo)

Omar Gamal, a 28-year-old pigeon keeper, stands next to his pigeon coop on his rooftop in the Egyptian capital's twin city of Giza on February 21, 2021, with the Pyramids of (R to L) Khufu (Cheops), Khafre (Chephren), and Menkaure (Menkheres) in the background. An ancient tradition handed down through the generations, the practice of domesticating pigeons stretches across borders from the banks of the Nile to north Africa and beyond, with people not only training birds for competitions, but also serving them up as a dining delicacy. (Photo by Khaled Desouki/AFP Photo)

A Chinese tourist visits the Mutianyu Great Wall covered in snow on February 23, 2021 in Beijing, China. Affected by the new coronavirus (COVID-19), the number of visitors to Mutianyu Great Wall in 2020 dropped by about 60%. (Photo by Lintao Zhang/Getty Images)