Boys play basketball in the facilities of Belarus' Republican Clinic of Speleotherapy within a salt mine, as part of their treatment, near the town of Soligorsk, south of Minsk, February 19, 2015. According to the state clinic, more than 7,000 children and adults seek medical treatment for respiratory illness each year in the subsurface chambers of its facilities, located 420 metres underground between layers of potassium and stone salts in an operational salt mine. (Photo by Vasily Fedosenko/Reuters)

Riot policemen stand in formation during street protests against the decision made by Burundi's ruling National Council for the Defence of Democracy-Forces for the Defence of Democracy (CNDD-FDD) party to allow President Pierre Nkurunziza to run for a third five-year term in office, in the capital Bujumbura, April 26, 2015. Police in the Burundian capital used water cannon and tear gas on Sunday to disperse protesters demonstrating against Nkurunziza seeking a third term, witnesses said, after the government banned protests for or against the move. (Photo by Thomas Mukoya/Reuters)

A sinkhole is seen on the shore of the Dead Sea near Kibbutz Ein Gedi, Israel July 27, 2015. The Dead Sea is shrinking, and as its waters vanish at a rate of more than one meter a year, hundreds of sinkholes, some the size of a basketball court, some two storeys deep, are devouring land where the shoreline once stood. (Photo by Amir Cohen/Reuters)

Job seekers carry a woman who fainted at the Indonesia Spectacular Job Fair 2015 at Gelora Bung Karno stadium in Jakarta August 12, 2015. Indonesia's gross domestic product grew at 4.67 percent in the second quarter, its slowest pace in six years. Since he took office last October, Widodo's government has passed a raft of measures aimed at boosting industry and consumption that have been criticized by investors as protectionist. (Photo by Reuters/Beawiharta)

Chief priest Gbenga Saala raises a cutlass to kill a dog during an annual prayer and sacrifice celebration of the iron god Ogun in Abuja, Nigeria, June 23, 2015. Every year worshippers offer a dog as sacrifice to Ogun, a traditional Nigerian deity, in hope of an auspicious year ahead. Taxi drivers, blacksmiths, panel beaters and mechanics – trades that depend on metal for their livelihood – pay homage to Ogun, led by high priest Gbenga Saala. As part of the ceremony, the priest pours the dog’s blood on symbols of these workers’ trade: keys, spanners and other tools piled up in a metal barrel. (Photo by Afolabi Sotunde/Reuters)

An Zi, is squashed amongst other commuters in a subway train on his way to work in Beijing, China, November 12, 2015. An, a movie producer, moved to Dongsanqi village in Changping this year. His commute to work can take about 2 hours, with transportation costs topping 200 yuan a month, or about a fifth of his monthly rent. (Photo by Jason Lee/Reuters)

Men sleep at a 24-hour McDonald's restaurant in Hong Kong, China November 10, 2015. A large number of homeless people sleeping on the street has long been been a problem in Hong Kong mainly due to its high rent and soaring property. In recent years, McDonald's 24-hour fast food shops opening all over the city have become popular alternatives for people, know as McRefugees or McSleepers, to spend the night in a safer and more comfortable way than on the street. (Photo by Tyrone Siu/Reuters)

Revellers participate in a parade on the street during a carnival in the village of Vevcani, south of Skopje, Macedonia January 13, 2016. Vevcani village marks the annual Orthodox St. Vasilij Day with a carnival that features a 1,400-year-old celebration with pagan roots. The highlights of the carnival include a political satire where masked villagers act out current events. (Photo by Ognen Teofilovski/Reuters)