Protesters wear gas masks in the front of the Romanian Environment Ministry in Bucharest March 4, 2019, to demand better air. Dozens of people holding placards reading “Our children don't breath air anymore” gather in the front of the Environment Ministry to ask for better breathable air in Bucharest. (Photo by Daniel Mihailescu/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)

South Korean environmental activists wearing masks symbolizing the coronavirus attend a prevention campaign as South Koreans take measures to protect themselves against the spread of coronavirus (COVID-19) on March 30, 2020 in Seoul, South Korea. South Korea has called for expanded public participation in social distancing, as the country witnesses a wave of community spread and imported infections leading to a resurgence in new cases of COVID-19. According to the Korea Center for Disease Control and Prevention on Monday, 78 new cases were reported. The total number of infections in the nation tallies at 9,661. (Photo by Chung Sung-Jun/Getty Images)

A lady wearing a mask feeds pigeons in St James' Park, as the spread of the coronavirus disease (COVID-19) continues, London, Britain, April 5, 2020. (Photo by Henry Nicholls/Reuters)

A masked tourist poses for a souvenir photo next to a graffiti titled “Mobile World Virus” depicting “La Gioconda”, aka Mona Lisa, with a mobile phone and a medical mask, by urban artist TVBoy, close to the Sant Jaume square in Barcelona, Spain, 09 March 2020. Barcelona's Deputy Mayor and two town councillors are in quarantine after they were in contact with a City Hall's worker who was tested positive for the COVID-19 coronavirus. (Photo by Quique Garcia/EPA/EFE)

Medical staff react outside Queen Elizabeth Hospital during the Clap for our Carers campaign in support of the NHS, as the spread of the coronavirus disease (COVID-19) continues, in Birmingham, Britain, April 23, 2020. (Photo by Carl Recine/Reuters)

Artists perform as people watch from the safety of their cars, during the Art Parking drive-in festival in Prague, Czech Republic, Sunday, April 26, 2020. Artists in Czech Republic are finding different ways to perform as regular theaters remain closed in an effort to stem the spread of coronavirus. (Photo by Petr David Josek/AP Photo)

A man wears a protective face mask as he walks along the main market in downtown after the government eased the restrictions on movement aimed at containing the spread of the coronavirus disease (COVID-19), in Amman, Jordan on April 29, 2020. (Photo by Muhammad Hamed/Reuters)