East Berliners crossing into the West Berlin on November 11, 1989 at the Potsdamer Platz, Germany. (Photo by Kai Wiedenhoefer)

A Filipino woman wears a mask to try and protect against the spread of coronavirus in Malate district, Manila City on March 24, 2020. The Philippines has taken drastic measures to combat the spread of Covid-19. The entire country is under strict quarantine and the army is on the streets to monitor compliance. According to official figures, there are 462 positive cases and 33 dead in the Philippines, but it is thought that thousands of cases remain undetected due to lack of resources in a country where millions of people have no access to health care. In the poorest and most crowded areas, it’s almost impossible to adhere to the physical distancing required during quarantine. (Photo by Alejandro Ernesto/The Guardian)

People view the sunrise scene at the Bund in Shanghai, east China, January 1, 2017. (Photo by Wang Hechun/Xinhua/Barcroft Images)

Paramilitary policemen take part in a training in Chaohu, Anhui province, China December 28, 2015. (Photo by Reuters/China Daily)

In this handout photo provided by Warner Brothers Pictures and Village Roadshow Pictures, Tom Cruise plays Lieutenant Colonel Bill Cage, a soldier who replays his last day while trying to fight aliens, in director Doug Liman's “All You Need Is Kill”. The film is set to premiere on March 14, 2014. (Photo by David James/Warner Brothers Pictures)

UK reality TV star Jemma Lucy enjoys a girls night out at Minagerie, Sakana and Club Liv in Manchester, England on September 18, 2016. (Photo by XposurePhotos.com)

A woman prays while touching the fingers of a Buddha statue during the annual Makha Bucha Day, which celebrates Buddha's teachings, in Ang Thong, Thailand February 11, 2017. (Photo by Jorge Silva/Reuters)

Lowry Park Zoo elephants Matjeka, 23, and her 1-year-old daughter, Mavi, apply a liberal coating of “sunscreen” to themselves in a clay mud wallow at the park Tuesday, August 12, 2014, in Tampa, Fla., on the park's first observation of World Elephant Day to raise awareness of the wild African elephant crisis. “Elephants are prone to being sunburned”, said associate curator Chris Massaro. “What they need is lot of mud or clay to roll around in and cover up their skin so it will protect it from the sun”. (Photo by Cherie Diez/AP Photo/The Tampa Bay Times)