An air plane takes off from the airport as air traffic is effected by the spread of the coronavirus disease (COVID-19) in Frankfurt, Germany, March 16, 2020. (Photo by Kai Pfaffenbach/Reuters)

A woman wearing a protective mask is seen behind a girl dressed in a Plague Doctor Mask in Western-Ukrainian city of Lviv, Ukraine, 22 March 2020. Ukrainian Designer Anastasia Markovska sewed protective masks looking like Plague Doctor Masks, the traditional costume of Venice Carnival, for herself and her friends due to the ongoing pandemic of the COVID-19 disease caused by the SARS-CoV-2 coronavirus. In Ukraine had been 47 laboratory-confirmed cases of COVID-19, including three deaths and one recovery as Ukraine's Health Ministry announced. (Photo by Pavlo Palamarchuk/EPA/EFE)

A four-legged robot dog called SPOT patrols a park as it undergoes testing to be deployed as a safe distancing ambassador, following the coronavirus disease (COVID-19) outbreak, in Singapore on May 8, 2020. (Photo by Edgar Su/Reuters)

A Palestinian boy dips in a natural spring to cool off during a heat wave, amid concerns about the spread of the coronavirus disease (COVID-19), near Jericho in the Israeli-occupied West Bank on May 17, 2020. (Photo by Mohamad Torokman/Reuters)

A police officer who was injured when falling of a horse during scuffles with demonstrators at Downing Street during a Black Lives Matter march in London, Saturday, June 6, 2020, is dragged by colleagues, as people protest against the killing of George Floyd by police officers in Minneapolis, USA. Floyd, a black man, died after he was restrained by Minneapolis police while in custody on May 25 in Minnesota. (Photo by Frank Augstein/AP Photo)

Lydia Hassebroek, 10, uses a magnifying glass to light a leaf on fire in her backyard during the outbreak of the coronavirus disease (COVID-19) in Brooklyn, New York, U.S., May 17, 2020. (Photo by Caitlin Ochs/Reuters)

A man wearing a face mask walks past a picture of a Russian tank in central Moscow on June 18, 2020. Russia's President Putin on June 24 will preside over a massive military parade to mark Soviet victory in World War II, which was postponed due to the coronavirus pandemic. (Photo by Yuri Kadobnov/AFP Photo)

A labourer carries sugarcane to load onto a mini truck at the main vegetable and fruit market in Islamabad on July 7, 2020. (Photo by Aamir Qureshi/AFP Photo)