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 swimmer swims by a swan in The Serpentine in Hyde Park, following the outbreak of the coronavirus disease (COVID-19), London, Britain, May 26, 2020. (Photo by John Sibley/Reuters)

A health worker dresses in a protective suit before starting to perform the coronavirus testing in an effort to stop the spread of the coronavirus disease (COVID-19) in the Kibera slum of Nairobi, Kenya, May 26, 2020. (Photo by Baz Ratner/Reuters)

Iranians wearing face masks against the Covid-19 coronavirus attends Laylat al-Qadr prayers, one of the holiest nights during the Muslim fasting month of Ramadan, outside a mosque in the Tehran, on May 13, 2020. (Photo by Atta Kenare/AFP Photo)

A cafe-restaurant staff stands outside as people drink coffee in Monastiraki district of Athens, on Monday, May 25, 2020. Greece restarted regular ferry services to its islands Monday, and cafes and restaurants were also back open for business as the country accelerated efforts to salvage its tourism season. (Photo by Petros Giannakouris/AP Photo)

This photo taken on May 20, 2020 shows elementary school students wearing wings to maintain social distancing amid concerns of the COVID-19 coronavirus, in a classroom in Taiyuan in China's northern Shanxi province. (Photo by AFP Photo/China Stringer Network)

A woman, her hands decorated with traditional henna, prays during Eid al-Fitr prayer at historical Badshahi mosque in Lahore, Pakistan, Sunday, May 24, 2020. (Photo by K.M. Chaudary/AP Photo)