A Chesterfield Borough Police telephone operator tests a gasmask with built in earpiece and microphone. The telephone service is considered one of the most important links in the coordination of ARP operations and must remain operational during air raids, 12th April 1939. (Photo by Fox Photos/Hulton Archive/Getty Images)

A health worker dresses in a protective suit before starting to perform the coronavirus testing in an effort to stop the spread of the coronavirus disease (COVID-19) in the Kibera slum of Nairobi, Kenya, May 26, 2020. (Photo by Baz Ratner/Reuters)

Volunteers wearing face masks, gloves and protective gear to protect against coronavirus, gather to clean an area of an outdoor book market set up at Red Square with GUM, State Department store, left, St. Basil's Cathedral, center, Spasskaya Tower, second with, and the Kremlin Wall, right, in Moscow, Russia, Saturday, June 6, 2020. Muscovites clad in face masks and gloves ventured into Red Square for an outdoor book market, a small sign of the Russian capital's gradual efforts to open up amid coronavirus concerns. (Photo by Alexander Zemlianichenko/AP Photo)

A Palestinian man carries a lion cub as he shows it to children in Rafah refugee camp in the southern Gaza Strip on December 4, 2019. (Photo by Ibraheem Abu Mustafa/Reuters)

The Duchess of Cambridge joins Family Action at a Christmas Tree Farm to mark her new patronage, in Great Missenden, Buckinghamshire, UK, on the 4th December 2019. (Photo by James Whatling/The Mega Agency)

Shannon Courtenay exchanges punches with Buchra El Quaissi during the Bantamweight between Shannon Courtenay and Buchra El Quaissi at York Hall on December 19, 2019 in London, England. (Photo by James Chance/Getty Images)

Three-year-old orangutan from Sumatra, Berani, is pictured at the Pairi Daiza wildlife park, zoo and botanical garden in Brugelette, Belgium on August 2, 2019. (Photo by Yves Herman/Reuters)

A grey-bellied Night Monkey (Aotus Lemurinus) plays with a teddy bear at the veterinary clinic of the Cali Zoo in Cali, Colombia on January 27, 2020. They monkey is being raised by personnel of the Cali Zoo after a worker found it near the complex. Apparently it fall from a tree with his father who had health problems. (Photo by Luis Robayo/AFP Photo)