Residents wearing masks to protect from the coronavirus cross a junction in Beijing on Wednesday, January 20, 2021. (Photo by Ng Han Guan/AP Photo)

In this September 17, 2010 file photo a little brown bat is photographed in La Crosse Wis. Researchers for the first time found that little brown bats appear to be showing resistance to white-nose syndrome, which has killed millions of bats across North America. (Photo by Peter Thomson/La Crosse Tribune via AP Photo)

Participants cross cold and muddy waters during the Strong Race competition near Tukums May 4, 2014. About 6500 people competed in this extreme running race, which includes cross-country running, elements of agility and power discipline. (Photo by Ints Kalnins/Reuters)

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

A man crosses Canal Street in the wind and rain from Hurricane Isaac August 29, 2012. (Photo by David J. Phillip/Associated Press)

North Kenya, Liboi. A young Somali refugee crosses a field filled with marabous storks in July 1992. (Photo by Jean-Claude Coutausse)

A father crosses a road with his twin daughters in Shanghai, China September 28, 2018. (Photo by Aly Song/Reuters)

People cross the street in central Pyongyang, North Korea May 4, 2016. (Photo by Damir Sagolj/Reuters)