A Chinese woman wears a mask to protect from particles blown in during a sandstorm as she walks in the street on May 4, 2017 in Beijing, China. Sandstorms are common in northern China during the spring season and are caused when heavy winds from Mongolia in the north brings sand and pollutants that can blanket Chinese cities and cause air quality to deteriorate. (Photo by Kevin Frayer/Getty Images)

A demonstrator sits on the coffin containing the body of a protester who was killed during previous protests in Port-au-Prince, Haiti, Monday, March 4, 2019. Protesters are angry about skyrocketing inflation and the government's failure to prosecute embezzlement from a multi-billion Venezuelan program that sent discounted oil to Haiti. (Photo by Dieu Nalio Chery/AP Photo)

Russian woman takes selfie near military vehicle during the rehearsal for a military parade in Moscow, Russia, 29 April 2019. Russia will hold a Victory Day military parade on 09 May 2019 to mark the 74th anniversary since the capitulation of Nazi Germany in 1945. (Photo by Yuri Kochetkov/EPA/EFE)

Iraqi forces gather during an operation to attack Islamic State militants in Mosul, Iraq, October 21, 2016. (Photo by Reuters/Stringer)

Comandos de Salvamento rescuers Maria Martinez (L) and Ana Chichilla attend to a wounded homeless man in San Salvador, El Salvador July 16, 2016. The man was attacked with a machete by suspected gang members. In 2015, El Salvador registered a record 103 homicides per 100,000 habitants, making it one of the most dangerous countries in the world outside a war zone. But for many young people who have few chances to distance themselves from rivalries between so-called maras in their schools and neighbourhoods, a civil-society organisation called the Comandos de Salvamento, or Rescue Corps, has been a refuge. (Photo by Jose Cabezas/Reuters)

A model wears a face mask to help prevent the spread of the coronavirus, designed by Iraqi designer Ziad Tariq at his workshop in Basra, Iraq, Monday, July 20, 2020. (Photo by Nabil al-Jurani/AP Photo)

A man wearing a protective mask poses for a picture with a giant Jade Rabbit installation ahead of celebrations for the Mid-Autumn Festival, amid the coronavirus disease (COVID-19) outbreak in Kuala Lumpur, Malaysia on September 18, 2020. (Photo by Lim Huey Teng/Reuters)

A Member of the Congress of South African Trade Unions (COSATU) joins other strikers as they take part in a nationwide strike over issues including corruption and job losses outside parliament in Johannesburg, South Africa, October 7, 2020. (Photo by Siphiwe Sibeko/Reuters)