Shanghai Ballet dancers wearing masks practise in a dance studio in Shanghai, China, as the country is hit by an outbreak of the novel coronavirus, February 20, 2020. (Photo by Aly Song/Reuters)

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)

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)

A policeman wearing a coronavirus-themed outfit composed of helmet, mace and shield, gestures towards a vendor (L) at a market to raise awareness about social distancing, during a government-imposed nationwide lockdown as a preventive measure against the COVID-19 coronavirus in Chennai, on April 2, 2020. (Photo by Arun Sankar/AFP Photo)

A robot, developed by start-up firm Asimov Robotics, holds a tray with face masks and sanitizer after the two robots were launched to spread awareness about the coronavirus, in Kochi, India, March 17, 2020. (Photo by Sivaram V/Reuters)

Volunteers throw a mixture of water, neem herb and turmeric as an alleged natural disinfectant on a street in a residential area during a government-imposed nationwide lockdown as a preventive measure against the COVID-19 coronavirus, in Chennai on April 7, 2020. (Photo by Arun Sankar/AFP Photo)

Some bats in the forested area of Guapiles, Costa Rica, 21 April 2020. (Photo by Jeffrey Arguedas/EPA/EFE)

Local youth representatives dressed a Stormtrooper and Darth Vader (L-in black) from the Star Wars film franchise patrol in a wooden boat around a submerged village to remind residents to stay at home during the enhanced community quarantine in suburban Manila on May 6, 2020, as part of government's efforts to combat the spread of the COVID-19 coronavirus. (Photo by Ted Aljibe/AFP Photo)