Humboldt Penguins swim in their pool as a keeper looks on through a spherical window during the annual stocktake press preview at London Zoo in Regents Park in London Monday, January 4, 2016. A requirement of ZSL London Zoo's license, the annual audit takes keepers a week to complete and all of the information is shared with zoos around the world via the International Species Information System, where it's used to manage the worldwide breeding programmes for endangered animals. (Photo by Alastair Grant/AP Photo)

Russian President Vladimir Putin, right, and North Korea's leader Kim Jong Un pose for photographers during their meeting in Vladivostok, Russia, Thursday, April 25, 2019. Putin and Kim are set to have one-on-one meeting at the Far Eastern State University on the Russky Island across a bridge from Vladivostok. The meeting will be followed by broader talks involving officials from both sides. (Photo by Alexander Zemlianichenko/AP Photo/Pool)

A woman wearing masks, stretches her arms in Hong Kong, Wednesday, February 19, 2020. Russia says it will temporarily ban Chinese nationals from entering the country amid the outbreak of the new virus centered in China that has infected more than 73,000 people. (Photo by Kin Cheung/AP 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)

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)

Peng Jing, 24, attends her wedding photography shoot after the lockdown was lifted in Wuhan, capital of Hubei province and China's epicentre of the novel coronavirus disease (COVID-19) outbreak, April 15, 2020. (Photo by Aly Song/Reuters)

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)

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