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)

Ukrainian Air Force officers attend a graduation ceremony at the National University of Defence of Ukraine in Kiev, April 24, 2015. (Photo by Gleb Garanich/Reuters)

A man carries the body of his son for burial after he was killed when a rooftop of his house collapsed due to heavy rain in the outskirts of Peshawar, Pakistan April 27, 2015. A severe storm in northwest Pakistan, dubbed a “mini-cyclone”, has killed 44 people and injured more than 200, officials said, raising their previous death toll. (Photo by Fayaz Aziz/Reuters)

Passengers wait for a train to depart from the Hankou Railway Station in Wuhan, central China's Hubei province, Friday January 13, 2017. Officials expect that Chinese travelers will make almost 3 billion trips during the holiday travel rush that starts runs through Feb. 21. These trips include intercity flights, trains and local bus rides to villages for China's 1.4 billion people. (Photo by Chinatopix via AP Photo)

A Syrian Democratic Forces (SDF) female fighter adjusts a mortar in northern Deir al-Zor province ahead of an offensive against Islamic State militants, Syria February 21, 2017. (Photo by Rodi Said/Reuters)

Commuters, some of them wearing masks as a precaution against the coronavirus ride an auto-rickshaw in Noida, outskirts of New Delhi, India, Thursday, July 16, 2020. (Photo by Altaf Qadri/AP Photo)

A woman wearing a protection face mask walks past a mural of a dog in Shanghai, China, 03 September 2020. Daily life in Shanghai is returning to normal while many people still wear protection masks on the street, which are still mandatory in many shopping malls and other public places. (Photo by Alex Plavevski/EPA/EFE)

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