Two F-15E Strike Eagles wait to receive fuel from a KC-135R Stratotanker during exercise Red Flag 15-1 on their way to Nellis Air Force Base, Nev., Jauary 23, 2015. The F-15s are assigned to the 4th Fighter Wing. U.S. (Photo by Airman 1st Class Aaron J. Jenne/Reuters)

Fr Pierre Pepper (C) warms up before his amateur boxing match in the town of Banagher in County Offaly March 15, 2015. Fr Pepper has spent the last two months training for an amateur boxing match to raise proceeds for charity. (Photo by Cathal McNaughton/Reuters)

Pakistani street performers sit around fire waiting for customers on a chilly evening in Rawalpindi, Pakistan, Wednesday, November 11, 2015. Some parts of Pakistan are facing a harsh winter. (Photo by B. K. Bangash/AP Photo)

A pro-democracy protester wearing a Guy Fawkes mask holds a yellow umbrella and a banner in the part of Hong Kong's financial central district protesters are occupying November 2, 2014. The former British colony of Hong Kong, which returned to Chinese rule in 1997, has witnessed a month of protests calling on the Beijing-backed government to keep its promise of introducing universal suffrage. The protests have for the most part been peaceful, with occasional clashes between the student-led protesters and Beijing supporters seeking to move them from the streets. (Photo by Damir Sagolj/Reuters)

A U.S. President Donald Trump mask is seen for sale in a market in Hong Kong, China on December 23, 2019. (Photo by Lucy Nicholson/Reuters)

The Greyfriars Bobby statue is pictured wearing a mask as the spread of the coronavirus disease (COVID-19) continues, in Edinburgh, Scotland, Britain, March 23, 2020. (Photo by Russell Cheyne/Reuters)

An Indian policeman wearing a virus themed helmet rides on a horse during an awareness rally aimed at preventing the spread of new coronavirus in Hyderabad, India, Thursday, April 2, 2020. (Photo by Mahesh Kumar A./AP Photo)

This picture taken on May 4, 2020 shows gentoo penguins chasing krill during feeding time in their enclosure at the Ocean Park theme park, which is currently closed due to the COVID-19 novel coronavirus, in Hong Kong. Save for an absence of gawping crowds, life for the penguins of Hong Kong's Ocean Park has been much the same during the coronavirus pandemic – but their carers have worked long shifts to keep the monochrome troupe healthy. (Photo by Anthony Wallace/AFP Photo)