Cambridge students the morning after the Trinity and Jesus college May Balls in Cambridge, United Kingdom on June 19, 2018. Students at Cambridge University celebrate the end of the academic year with the May Balls. (Photo by South West News Service)

In this April 14, 2014 file photo, Hamamatou Harouna, 10, who lost the use of her legs to polio, crawls to the restroom on the grounds of the Catholic Church where she and hundreds of others found refuge after fleeing violence in her village, in Carnot, Central African Republic. Health authorities on Tuesday, August 25, 2020 are expected to declare the African continent free of the wild poliovirus after decades of effort, though cases of vaccine-derived polio are still sparking outbreaks of the paralyzing disease in more than a dozen countries. (Photo by Jerome Delay/AP Photo/File)

A dancer warms up along 34th Street while waiting to perform during a pre-taping of the Macy's Thanksgiving Day Parade in front of the flagship store in New York, Wednesday, November 25, 2020. (Photo by Mary Altaffer/AP Photo)

A woman wears a face mask on her chin and walks past a cake depicting the coronavirus on display at the annual cake show organized as part of new year celebrations in Bengaluru, India, Tuesday, December 29, 2020. India's confirmed coronavirus cases have crossed 10 million with new infections dipping to their lowest levels in three months, as the country prepares for a massive COVID-19 vaccination in the new year. (Photo by Aijaz Rahi/AP Photo)

Rajesh Babu, a police officer, wearing a helmet depicting coronavirus, requests a commuter to stay at home during a 21-day nationwide lockdown to limit the spreading of coronavirus disease (COVID-19), in Chennai, India, March 28, 2020. (Photo by P. Ravikumar/Reuters)

A cyclist rides the path around Lake Harriet on Memorial Day in Minneapolis on Monday, May 25, 2020. The area around the Lake Harriet Bandshell was busy but not crowded on Memorial Day evening. (Photo by Jeff Wheeler/Star Tribune via AP Photo)

A traditional large puppet figure known as “Ondel-ondel”, wearing a face mask, performs on a sidewalk of the main road, as the outbreak of the coronavirus disease (COVID-19) continues in Jakarta, Indonesia, January 4, 2021. (Photo by Willy Kurniawan/Reuters)

Farmers take a break for lunch while celebrating National Paddy Day, also called Asar Pandra, that marks the commencement of rice crop planting in paddy fields as monsoon season arrives, in Kathmandu, Nepal, June 29, 2020. (Photo by Navesh Chitrakar/Reuters)