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)

This file photo provided on Sunday February 15, 2015 by the Syrian anti-government activist group Aleppo Media Center (AMC), which has been authenticated based on its contents and other AP reporting, shows Syrian rebels firing locally made shells against the Syrian government forces, in Aleppo, Syria. (Photo by AP Photo/Aleppo Media Center)

Almost two years old male baby orang-utan Dalai looks on in the zoo in Dresden, Germany, 30 March 2017. Dalai was born to mother Daisy in June 2016. (Photo by Filip Singer/EPA)

Haitians pull a car atop a pushcart in Port-au-Prince, October 11, 1994. The price of gasoline has fallen to about $6 US per gallon since U.S. forces occupied Haiti. Before, gasoline had cost as much as $10 U.S. per gallon. (Photo by Eric Draper/AP Photo)

WrestlerTeddy Sheedi (L) fights his opponent during the traditional Sindhi Malakhra wrestling in Karachi, Pakistan, 13 December 2020. A Malakhra match begins with both wrestlers tying a twisted cloth around the opponent's waist. Each one then holds onto the opponent's waistcloth and tries to throw him to the ground. (Photo by Shahzaib Akber/EPA/EFE)

A shopkeeper wears a face mask as a precaution against the coronavirus waits for customers at a market in Bengaluru, India, Friday, November 20, 2020. India's total number of coronavirus cases since the pandemic began has crossed 9 million. Nevertheless the country's new daily cases have seen a steady decline for weeks now and the total number of cases represents 0.6% of India's 1.3 billion population. (Photo by Aijaz Rahi/AP Photo)

The Aurora Borealis (Northern Lights) is seen over the sky near Inari in Lapland, Finland on February 14, 2019. (Photo by Alexander Kuznetsov/Reuters)

A man walks by as tourists take selfies on the French Riviera city of Nice on June 24, 2019, as temperatures soar to 33 degrees Celsius. Forecasters say Europeans will feel sizzling heat this week with temperatures soaring as high as 40 degrees Celsius (104 degrees Fahrenheit) in an “unprecedented” June heatwave hitting much of Western Europe. (Photo by Valery Hache/AFP Photo)