In this photograph taken on February 18, 2016, Pakistani children ride on swings in the predominantly Pashtun Korangi District of Karachi. In a rundown district of Karachi, Rabia balks at a neighbour's proposal to vaccinate her children, demonstrating one of the biggest hurdles to eradicating polio in Pakistan by the end of the year: confused and frightened parents. (Photo by Asif Hassan/AFP Photo)

People walk during a polluted day in Shenyang, Liaoning province, March 31, 2016. (Photo by Reuters/Stringer)

The six-months-old female koala cub holds on to the back of zoo keeper Lena at the zoo in Duisburg, Germany, 23 October 2015. The yet unnamed baby weighs 580 grams. (Photo by Roland Weihrauch/EPA)

People socialising in Soho, central London on July 11, 2020, after the lifting of further coronavirus lockdown restrictions in England. Revellers are urged to remember the importance of social distancing as pubs gear up for the second weekend of trade since the lifting of lockdown measures. (Photo by Stefan Rousseau/PA Images via Getty Images)

An actor dressed as Santa Claus and wearing a face mask to protect against coronavirus infection speaks with a boy during the New Year celebration in a shopping mall in St.Petersburg, Russia, Saturday, January 2, 2021. (Photo by Dmitri Lovetsky/AP Photo)

Forensic investigators look at the body of a man infected with the new coronavirus who collapsed on the street and died, according to Police Captain Diego Lopez, in Quito, Ecuador, Tuesday, May 5, 2020. (Photo by Dolores Ochoa/AP Photo)

A Palestinian woman argues with an Israeli border policewoman over the Israeli demolition of a building housing an apartment and a restaurant as the building owners said they were informed by the forces that they did not obtain a construction permit, in Beit Jala in the Israeli-occupied West Bank on August 26, 2019. (Photo by Mussa Qawasma/Reuters)

In this picture taken on December 13, 2017, a woman commutes on a street on a cold day in Baoding. As temperatures dipped below freezing in a northern Chinese village, a group of parka-clad women tried to stay warm as they played mahjong around a small gas stove in a grocery store. (Photo by Fred Dufour/AFP Photo)