In this April 14, 2014 file photo, Hamamatou Harouna, 10, who lost the use of her legs to polio, crawls to the restroom on the grounds of the Catholic Church where she and hundreds of others found refuge after fleeing violence in her village, in Carnot, Central African Republic. Health authorities on Tuesday, August 25, 2020 are expected to declare the African continent free of the wild poliovirus after decades of effort, though cases of vaccine-derived polio are still sparking outbreaks of the paralyzing disease in more than a dozen countries. (Photo by Jerome Delay/AP Photo/File)

Orphaned mountain gorilla, Ndakasi, lies in the arms of her caregiver, Andre Bauma, on September 21, 2021 shortly before her death, which the park confirmed on September 26. Mr Bauma and others at the Senkwekwe Mountain Gorilla Center had cared for Ndakasi and other orphans for 13 years. Ndakasi had suffered a prolonged illness prior to her death. This is the only mountain gorilla orphanage in the world and takes in mountain gorilla orphans who have lost their families to poaching or conflict. A number of the orphans here were rescued from sales by poachers in sting operations carried out by Congolese National Park Authority (ICCN) rangers. (Photo by Brent Stirton/Getty Images)

Chinese epidemic control workers wear protective suits as they disinfect each other after performing nucleic acid swab test for COVID-19 on citizens at a government testing site in Xicheng District during an organized tour on June 24, 2020 in Beijing, China. While Chinese government medical officials have said they believe they have controlled the spread, authorities are trying to contain the outbreak linked to the Xinfadi wholesale food market, Beijing's biggest supplier of produce and meat. (Photo by Kevin Frayer/Getty Images)

A young girl makes a “tomato angel” on a tomato covered street during the traditional tomato fight “Tomatina” during the fiestas in Bunol, Spain, 28 August 2013. This year's Tomatina is the first pay festival after Bunol's City Hall sold 15,000 tickets to take part in the tomato throwing. A total of 20,000 people, including 5,000 residents, will throw over 130,000 kg tomatoes. Local authorities decided to sell tickets this year to avoid the overcrowding in previous years in which over 50,000 people took part in the event. (Photo by Biel Alino/EPA)

Boys pan for gold on a riverside at Iga Barriere, 25 km (15 miles) from Bunia, in the resource-rich Ituri region of eastern Congo February 16, 2009. Ituri is one of many areas of the country to have experienced bitter ethnic conflict between rival tribes in recent years. Massacres have left tens of thousands dead. It is this fighting that led U.S. authorities to take the unprecedented step of naming Congo in section 1502 of the Dodd-Frank financial regulation act, which says U.S.-listed companies that source gold, tungsten, tantalum and tin from Congo or its neighbours must assure the U.S. stock exchange regulator that their business is not helping fund conflict. (Photo by Finbarr O'Reilly/Reuters)

Cuban migrant Yamilen Arbelo, 40, walks down a hill as she crosses the border from Colombia through the jungle into La Miel, in the province of Guna Yala, Panama November 29, 2015. According to local authorities in La Miel, some 100 to 150 Cubans have been entering Panama from Colombia every day for the last three months. Scores of Cubans have come to Panama as they seek overland passage towards the United States fearing a recent detente between Washington and Havana could end their preferential treatment. (Photo by Carlos Jasso/Reuters)

South African Sangomas are wizards and witches who are supposedly chosen by their ancestors to follow a traditional training and go through a rite of passage after which they become Sangomas and can cure and help people. They are so respected and trusted that western medical authorities have actually advised the government of South Africa to develop its cooperation with Sangomas in order to improve hygiene and health among the population. (Photo by Patrick Durand/Sygma via Getty Images)

Brandy Shelton of Greensboro, North Carolina, “twerks” for a group of bikers on Ocean Boulevard during the 2015 Atlantic Beach Memorial Day BikeFest in Myrtle Beach, South Carolina May 22, 2015. After three people were killed and seven wounded in shootings during 2014 Bikefest, State officials called for an end to the event that draws thousands to the family-friendly beach town.Their efforts were unsuccessful. Bikers returned to Myrtle Beach – just a week after a bloody motorcycle gang shootout in Waco, Texas. But this time authorities are more prepared, with dozens of new surveillance cameras and a police force three times the size of last year's. (Photo by Randall Hill/Reuters)