A flight crew from China Airlines, wearing protective masks, stand in the international terminal after arriving on a flight from Taipei at Los Angeles International Airport (LAX) on February 28, 2020 in Los Angeles, California. The World Health Organization (WHO) has raised the global coronavirus risk level to “very high”. (Photo by Mario Tama/Getty Images)

Aerial view of tourists in life vests and rubber rafts in the Grand Canyon of western Henan, Sanmenxia, China on August 5, 2017. (Photo by Imaginechina/Rex Features/Shutterstock)

A general view shows smoke and volcanic ashes billowing from volcano Cotopaxi in Pedregal, Ecuador, late 07 October 2015. (Photo by Jose Jacome/EPA)

A morning fog is seen in the Siberian city of Omsk, Russia on October 8, 2019. (Photo by Alexey Malgavko/Reuters)

North Korean women in colorful traditional dresses are surrounded by flower blossoms known as “Kimilsungia” as they wait to guide guests at a flower exhibition in Pyongyang, North Korea, April 14, 2014. The flowers, named after Kim Il Sung, are on display to celebrate the late leader's official birth date of April 15, 1912. (Photo by David Guttenfelder/AP Photo)

Balinese man watches Mount Agung volcano almost covered with clouds as he stands at a temple in Karangasem, Bali, Indonesia, Tuesday, September 26, 2017. An increasing frequency of tremors from the volcano indicates magma is continuing to move toward the surface and an eruption is possible, a disaster agency official said Tuesday. Tourists are cutting short their stay to the island, where an eruption would force the airport to close and strand thousands. (Photo by Firdia Lisnawati/AP Photo)

An Iraqi special forces soldier shot dead an Islamic State suicide bomber in Mosul, Iraq March 3, 2017. (Photo by Goran Tomasevic/Reuters)

An member of the group “Pause the System” wears a face mask as she protests in front of the entrance to Downing Street in London, Friday, March 20, 2020. For most people, the new coronavirus causes only mild or moderate symptoms, such as fever and cough. For some, especially older adults and people with existing health problems, it can cause more severe illness, including pneumonia. (Photo by Frank Augstein/AP Photo)