A health worker administers a dose of the Sinovac COVID-19 vaccine to a worker in a local entertainment venue area where a new cluster of COVID-19 infections were found in Bangkok, Thailand, Wednesday, April 7, 2021. Officials in Thailand’s capital have ordered a two-week closure of all entertainment venues in three districts to try to limit the spread of the coronavirus from nightspots there. (Photo by Sakchai Lalit/AP Photo)

Russian President Vladimir Putin, right, and North Korea's leader Kim Jong Un pose for photographers during their meeting in Vladivostok, Russia, Thursday, April 25, 2019. Putin and Kim are set to have one-on-one meeting at the Far Eastern State University on the Russky Island across a bridge from Vladivostok. The meeting will be followed by broader talks involving officials from both sides. (Photo by Alexander Zemlianichenko/AP Photo/Pool)

This photo taken on December 2, 2015 shows a lenticular cloud forming as white streaks from airplanes mark the blue sky, in a rare atmospheric phenomena above the town of Gevgelija on December 2, 2015. Lenticular clouds have been regularly confused for UFOs throughout history due to the their smooth, round or oval lens-shaped structure. (Photo by Armend Nimani/AFP Photo)

An Indian lift operator stands inside a dedicated lift for people suspected to be infected with the new corona virus at the Government Gandhi Hospital in Hyderabad, India, Monday, March 2, 2020. Coronavirus has spread to more than 60 countries, and more than 3,000 people have died from the COVID-19 illness it causes. (Photo by Mahesh Kumar A./AP Photo)

A cleaning staff waers protective gear to disinfect a metro carriage as a prevemtive measure against the spreading of the COVID-19 coronavirus in Addis Ababa, Ethiopia, on March 20, 2020. African countries have been among the last to be hit by the global COVID-19 coronavirus epidemic but as cases rise, many nations are now taking strict measures to block the deadly illness. (Photo by Michael Tewelde/AFP Photo)

Paramedics wearing protective suits amid fears of coronavirus outbreak check on a man who collapsed outside a clinic in Jakarta, Indonesia, Thursday, March 26, 2020. It's not immediately clear what caused the man to collapse. The U.S. Embassy in Indonesia has ordered the departure of employees' family members under the age of 21 from its missions in the country where new COVID-19 patients have surged in the past week with high fatality. (Photo by Muchlis Akbar/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)

People wear face masks while participating in the annual Memorial Day Parade on May 25, 2020 in the Staten Island borough of New York City. Dozens of cars and nearly 100 members of the patriotic motorcycle group Rolling Thunder joined the event. This year’s parade was diminished in size and in person-to-person contact due to the coronavirus outbreak. Across the country, events honoring the nation’s veterans have been cancelled or scaled back as America continues to experience high numbers of deaths and new cases of COVID-19. (Photo by Spencer Platt/Getty Images)