Eight year-old Maya Mohammad Ali Merhi walks using prosthetic legs made by her father from tin cans in a camp for displaced people, in the northern Syrian province of Idlib on June 20, 2018. Maya and her father were both born without lower limbs. Unable to afford real prosthetic limbs, her father made her a pair out of tin cans filled with cotton and scrap pieces of cloth. Maya's family had to leave their home in the Aleppo province to flee battles. (Photo by Aaref Watad/AFP Photo)

A woman waits at a polio immunisation health centre, in Maiduguri, Borno State, Nigeria, August 29, 2016. Nigeria's military has liberated large swathes of land from Boko Haram but a ride with an army convoy, all guns firing for fear of ambush, shows how far the northeast is from normality after a brutal Islamist insurgency that has displaced millions. (Photo by Afolabi Sotunde/Reuters)

The unromantic gypsies. Children boxing in a gypsy camp in Kent, England on July 1, 1951. Like all boys these gypsy lads like to try their hand at boxing. Encouraged by their friends they fight it out on Corke's Meadow. Few Romanies now live a life of wandering romance. Most are like the three hundred squatters of Corke's Meadow, Kent, which is part of a “gypsy problem” that involves about 100,000 today. Of those about 25,000 can be rightly called gypsies, the rest are Mumpers and Posh-rats and Hobos. Corke's Meadow has both kinds. “Picture Post” cameraman Bert Hardy photographs the Corke's Meadow gypsies in their encampment. (Photo by Hulton-Deutsch Collection/Corbis via Getty Images)

A woman sweeps an alleyway adorned with murals painted by artists from “Delhi Street Art” group at the Raghubir Nagar slum in New Delhi on December 2, 2019. A New Delhi slum has been given a colourful makeover thanks to a street artist collective, drawing art lovers and selfie-snappers to a rundown area that they would never normally visit. (Photo by Sajjad Hussain/AFP Photo)

Vaccinators wear protective masks as they get their temperature checked, during an anti-polio campaign, in a low-income neighborhood as the spread of the coronavirus disease (COVID-19) continues, in Karachi, Pakistan on July 20, 2020. (Photo by Akhtar Soomro/Reuters)

People enjoying the hot weather on Brighton beach in Sussex, England on August 7, 2020. (Photo by Stephen Lock/i-Images)

Majesty Davis, 3, cries while visiting Santa Claus, who sits behind a plexiglass divider due to the coronavirus disease (COVID-19) pandemic, at the Willow Grove Park Mall in Willow Grove, Pennsylvania, U.S. November 14, 2020. (Photo by Mark Makela/Reuters)

Mortuary workers take off their protective clothing at the entrance of a building decorated with a Christmas tree, after removing the body of person who allegedly died of COVID-19 in Barcelona, Spain, Wednesday, December 23, 2020. (Photo by Emilio Morenatti/AP Photo)