Men cover their heads from the sun while riding on a motorcycle during a hot day in Cairo, Egypt, August 17, 2015. A heatwave killed at least 61 people across Egypt from Sunday to Tuesday and caused nearly 600 people to be admitted to hospital, Egypt's health ministry said on state news agency MENA on Wednesday. (Photo by Amr Abdallah Dalsh/Reuters)

A giant panda cub is pictured in an incubator at the Ya'an Bifengxia Giant Panda Breeding and Research Center in Ya'an city, southwest China's Sichuan province, 21 August 2015. Ten tiny panda cubs made their first public appearance at China's Ya'an Bifengxia Giant Panda Breeding and Research Center in southwestern Sichuan province on Friday (21 August 2015). All of the ten giant pandas were born in 2015. The oldest of them is just two month old, while the youngest one was born a week ago. This marks the first time they were put together as a group since they were born. (Photo by Imaginechina/Splash News)

In this Monday, July 24, 2017 photo, a police officer walks in front of a mural during a protest demanding an end to the current pension fund system, in Santiago, Chile. Protesters say the government pension system robs retirees of fair pension payments, and are demanding a new social security system with higher payments. (Photo by Esteban Felix/AP Photo)

Since Rodrigo Duterte became president last year, his brutal campaign against drugs has claimed thousands of lives. Human rights groups say he is guilty of crimes against humanity, yet that is scant comfort to those mourning loved ones. Here: Constantino de Juan’s seven children sit on a sofa that still bears the bullet hole from their father’s shooting. Juan was preparing a spaghetti dinner on his daughter’s birthday when he was killed. (Photo by James Whitlow Delano/Funded by the Pulitzer Center on Crisis Reporting/The Guardian)

A Cambodian man rides his motor-cart loaded with goods along a street on the outskirts Phnom Penh, Cambodia on October 30, 2017. (Photo by Tang Chhin Sothy/AFP Photo)

Chloe Lewis attends “The Ony Way Is Essex” season finale filming in Wintney, Hook, England on October 29, 2017. (Photo by Beretta/Sims/Rex Features/Shutterstock)

The finishing touches are made to a new wax figure of Theresa May at Madame Tussauds in London, England on November 7, 2017. (Photo by Victoria Jones/PA Wire)

Common squirrel monkeys observe their Christmas present, a box full of mealworms, at the South America enclosure of the Budapest Zoo, in Budapest, Hungary, 24 December 2017. (Photo by Photo by Attila Kovacs/EPA/EFE/Rex Features/Shutterstock)