A student aims a stick of wood at Bolivarian National Police officers during clashes outside the Central University in Caracas, Venezuela, Thursday, June 9, 2016. Students had planned to march from Venezuela's top university to elections headquarters, but hundreds of police in riot gear blocked the way. Students covered their faces with Venezuelan flags and threw bottles, stones and sticks while police lobbed tear gas. (Photo by Fernando Llano/AP Photo)

An environmental activist adjusts his mask while taking part in “The Dead Sea Swim Challenge”, swimming from the Jordanian to Israeli shore, to draw attention to the ecological threats facing the Dead Sea, in Kibbutz Ein Gedi, Israel November 15, 2016. Swimmers from around the world plunged into the salty waters of the Dead Sea on Tuesday to attempt a seven-hour swim across the fabled lake in a bid to draw attention to its environmental degradation. Wearing protective masks and snorkels, 25 swimmers paddled through the muddy water to attempt the 9-mile (15-kilometer) swim from Jordan to Israel. (Photo by Nir Elias/Reuters)

A Ballet Paraisópolis student wearing a face mask rehearses amidst the coronavirus (COVID-19) pandemic on August 13, 2020 in Sao Paulo, Brazil. The Ballet Paraisópolis is a project that teaches dance to children and young people in the Paraisópolis community in order to encourage them to seek better life opportunities. Founded in 2012 by ballerina, teacher and choreographer, Monica Tarragó, Ballet Paraisópolis has a total of 200 students and another 2,000 on the waiting list. (Photo by Alexandre Schneider/Getty Images)

Nina Bahinskaya, 73, poses for a photo holding an old Belarusian national flag at an entrance of her apartment building in Minsk, Belarus, Thursday, September 10, 2020. The 73-year-old former geologist has become one of the most recognizable faces of Belarus protests, fearlessly waving a huge opposition's red-and-white flag in front of riot police. (Photo by AP Photo/Stringer)

In this October 6, 1976, file photo, a right-wing student, center foreground, draws his arm back to strike a captured and wounded leftist student being taken by police to an ambulance in during a student massacre in Bangkok, Thailand. This year’s anti-government protests are seeking new elections, a more democratic constitution and an end to intimidation of political activists. Their speeches have repeatedly highlighted the 1976 tragedy, piquing the interest of the current generation in what their forebears faced. (Photo by Neal Ulevich/AP Photo/File)

An Iranian woman wearing a face mask walks on a street in Tehran, Iran, 19 October 2020. According to the Iranian Health ministry, Iran reported its highest daily COVID-19 death toll of 337 and 4,251 new infections in past 24 hours as it appears that Iran is in a third wave of COVID-19 outbreak. (Photo by Abedin Taherkenareh/EPA/EFE)

A woman wearing a face mask takes a photo on her phone in Covent Garden, London, Thursday, December 3, 2020. Britain became the first country in the world to authorize a rigorously tested COVID-19 vaccine Wednesday and could be dispensing shots within days – a historic step toward eventually ending the outbreak that has killed more than 1.4 million people around the globe. (Photo by Alberto Pezzali/AP Photo)

A vegetable vendor wearing gloves and face mask as a precaution against the coronavirus interacts with a customer in Bengaluru, India, Sunday, October 11, 2020. India's confirmed coronavirus toll crossed 7 million on Sunday with a number of new cases dipping in recent weeks, even as health experts warn of mask and distancing fatigue setting in. (Photo by Aijaz Rahi/AP Photo)