In this March 30, 2020, photo, Zandile Mlotshwa, 21, cashier at Spar supermarket in the Norwood suburb of Johannesburg, counts her cash at the end of her shift. From South Africa to Italy to the U.S., grocery workers – many in low-wage jobs – are manning the front lines amid worldwide lockdowns, their work deemed essential to keep food and critical goods flowing. (Photo by Jerome Delay/AP Photo)

A man crosses a mud-covered trail carrying his wife on his back at a flooded Han River park in Seoul, South Korea, August 4, 2020. (Photo by Kim Hong-Ji/Reuters)

A dog plays amid a heavy snowfall in Madrid on January 9, 2021. Heavy snow fell across much of Spain, leaving huge areas blanketed in white as Storm Filomena brought wintry weather not seen in decades to the Iberian peninsula. (Photo by Benjamin Cremel/AFP Photo)

A Hindu sadhu (holy man) smears coloured paste onto his face ahead of the forthcoming Hindu festival of “Maha Shivaratri” at the Pashupatinath temple in Kathmandu on February 11, 2018. Hindus mark the “Maha Shivratri” festival by offering special prayers and fasting, with sadhus arriving at Pashupatinath to take part in the event, which takes place on February 13. (Photo by Prakash Mathema/AFP Photo)

Partygoers in Cardiff, England refused to let the rain dampen their Christmas spirits on “Thirsty Thursday”, December 19, 2018. Christmas partygoers got into the party spirit last night as they headed out for some festive fun up and down the country. (Photo by Huw Evans Picture Agency)

Clowns Perlita and Tapetito, wearing protective gear amid the new coronavirus pandemic, speak with resident Enrique Zeballos as they arrive to disinfect his home free of charge, in El Alto, Bolivia, Friday, September 11, 2020. The lack of traditional employment for the clowns due to the pandemic has led them towards other avenues of making money. But for people with limited income they provide their disinfection services free of charge. (Photo by Juan Karita/AP Photo)

School teachers and staff members take part during an active shooter training at James I. O'Neill High School in Highland Falls, New York, U.S., December 12, 2017. (Photo by Eduardo Munoz/Reuters)

Two and a half year-old Jennifer Martin in tears during a visit to Santa at Harrods department store in London, 10th December 1949. (Photo by William Vanderson/Fox Photos/Hulton Archive/Getty Images)