A drone picture shows hotel Przystan, closed due to the measures to halt the spread of the coronavirus disease (COVID-19) in Olsztyn, Poland, March 2, 2021. Picture taken March 2, 2021. REUTERS/Kuba Stezycki

A picture shows the empty interior of Primary School number 3, closed due to the measures to halt the spread of the coronavirus disease (COVID-19) in Nidzica, Poland, March 2, 2021. Picture taken March 2, 2021. REUTERS/Kuba Stezycki

A picture shows the empty interior of Primary School number 3, closed due to the measures to halt the spread of the coronavirus disease (COVID-19) in Nidzica, Poland, March 2, 2021. Picture taken March 2, 2021. REUTERS/Kuba Stezycki

A picture shows the empty interior of Olsztyn-Mazury Airport amid the coronavirus disease (COVID-19) pandemic, near Olsztyn, Poland, March 2, 2021. Picture taken March 2, 2021. REUTERS/Kuba Stezycki

A drone picture shows the Sasek lake in Warmian-Masurian Voivodeship amid the coronavirus disease (COVID-19) pandemic, near Olsztyn, Poland, March 2, 2021. Picture taken March 2, 2021. REUTERS/Kuba Stezycki

A view shows posters reading "The music never stops" at the Ariston Theatre during the 71st Sanremo festival, which is live-streamed without public participation due to the coronavirus disease (COVID-19) restrictions, in Sanremo, Italy March 2, 2021. REUTERS/Alessandro Garofalo

Aerial view shows Greenpeace's Arctic Sunrise ship departing for its first expedition from the Port of Victoria on Mahe Island, Seychelles March 2, 2021. Picture taken with a drone. REUTERS/Christophe Van Der Perre

Aerial view shows Greenpeace's Arctic Sunrise ship departing for its first expedition from the Port of Victoria on Mahe Island, Seychelles March 2, 2021. Picture taken with a drone. REUTERS/Christophe Van Der Perre

Aerial view shows Greenpeace's Arctic Sunrise ship departing for its first expedition from the Port of Victoria on Mahe Island, Seychelles March 2, 2021. Picture taken with a drone. REUTERS/Christophe Van Der Perre

Aerial view shows Greenpeace's Arctic Sunrise ship departing for its first expedition from the Port of Victoria on Mahe Island, Seychelles March 2, 2021. Picture taken with a drone. REUTERS/Christophe Van Der Perre

Aerial view shows Greenpeace's Arctic Sunrise ship departing for its first expedition from the Port of Victoria on Mahe Island, Seychelles March 2, 2021. Picture taken with a drone. REUTERS/Christophe Van Der Perre

An Indigenous woman shows her vaccination card after receiving the second dose of Sinovac's CoronaVac coronavirus disease (COVID-19) vaccine at a health station, in Guarulhos, near Sao Paulo, Brazil March 2, 2021. REUTERS/Carla Carniel

Indigenous people show their vaccination cards after receiving the second dose of Sinovac's CoronaVac coronavirus disease (COVID-19) vaccine at a health station, in Guarulhos, near Sao Paulo, Brazil March 2, 2021. REUTERS/Carla Carniel

An Indigenous woman shows her vaccination card after receiving the second dose of Sinovac's CoronaVac coronavirus disease (COVID-19) vaccine at a health station, in Guarulhos, near Sao Paulo, Brazil March 2, 2021. REUTERS/Carla Carniel

A Dutch sex worker performs in a peep show on wheels during a demonstration to demand the right to go back to work, amid the coronavirus disease (COVID-19) pandemic, in The Hague, Netherlands March 2, 2021. REUTERS/Piroschka Van De Wouw

People take photos of a Dutch sex worker performing in a peep show on wheels during a demonstration to demand the right to go back to work, amid the coronavirus disease (COVID-19) pandemic, in The Hague, Netherlands March 2, 2021. REUTERS/Piroschka Van De Wouw

A view shows the centre of Bratsk in Irkutsk Region, Russia March 2, 2021. REUTERS/Maxim Shemetov

A view shows a monument to the Soviet state founder Vladimir Lenin in Bratsk in Irkutsk Region, Russia March 2, 2021. REUTERS/Maxim Shemetov

Chart showing how the average life span and mass of bats compare to other species. Bats have relatively long life spans for their body size, which can make it easier for viruses to persist as chronic infections are more common.

Graphic showing bat species and families, and which of those have been responsible for outbreaks in the past.

An Iraqi health worker looks on as he shows a coronavirus disease (COVID-19) vaccine in Baghdad, Iraq March 2, 2021. REUTERS/Khalid al-Mousily

A health worker shows a vial of Sinovac Biotech’s Coronavac during the vaccination of Philippine military at the national headquarters of the Philippine Army in Fort Bonifacio, Taguig City, Metro Manila, Philippines, March 2, 2021. REUTERS/Eloisa Lopez

A view shows the Grand Immaculate Church, ahead of the planned visit of Pope Francis to Iraq, in Qaraqosh, Iraq February 23, 2021. Picture taken February 23, 2021. Picture taken with a drone REUTERS/Thaier al-Sudani

A view shows the Christian town of Qaraqosh, Iraq February 23, 2021. Picture taken February 23 2021. Picture taken with a drone. REUTERS/Thaier al-Sudani

A view shows the Grand Immaculate Church, ahead of the planned visit of Pope Francis to Iraq, in Qaraqosh, Iraq February 23, 2021. Picture taken February 23, 2021. Picture taken with a drone REUTERS/Thaier al-Sudani

A view shows the Grand Immaculate Church, ahead of the planned visit of Pope Francis to Iraq, in Qaraqosh, Iraq February 23, 2021. Picture taken February 23, 2021. Picture taken with a drone REUTERS/Thaier al-Sudani

A view shows the Christian town of Qaraqosh, Iraq February 23, 2021. Picture taken February 23 2021. Picture taken with a drone. REUTERS/Thaier al-Sudani

A view shows the Christian town of Qaraqosh, Iraq February 16, 2021. Picture taken February 16 2021. REUTERS/Thaier al-Sudani

A view shows the Christian town of Qaraqosh, Iraq February 16, 2021. Picture taken February 16 2021. REUTERS/Thaier al-Sudani

A view shows the Grand Immaculate Church, ahead of the planned visit of Pope Francis to Iraq, in Qaraqosh, Iraq February 25, 2021. Picture taken February 25, 2021. REUTERS/Thaier al-Sudani

A Kashmiri shopkeeper selling copperware shows a samovar to a customer at his shop in downtown Srinagar March 1, 2021. Picture taken March 1, 2021. REUTERS/Sanna Irshad Mattoo

A girl who was kidnapped from a boarding school in the northwest Nigerian state of Zamfara, shows her injured foot after her release in Zamfara, Nigeria March 2, 2021. REUTERS/Afolabi Sotunde

A health worker shows a vial of Sinovac Biotech’s Coronavac during the vaccination of Philippine military at the national headquarters of the Philippine Army in Fort Bonifacio, Taguig City, Metro Manila, Philippines, March 2, 2021. REUTERS / Eloisa Lopez

A Philippine military officer shows his sticker indicating that he has received COVID-19 vaccine, after being injected with Sinovac Biotech’s CoronaVac at the national headquarters of the Philippine Army in Fort Bonifacio, Taguig City, Metro Manila, Philippines, March 2, 2021. REUTERS/Eloisa Lopez REFILE - CORRECTING INFORMATION TPX IMAGES OF THE DAY

A health worker shows a vial and a box of Sinovac Biotech's Coronavac vaccine for the coronavirus disease (COVID-19), at the Marikina Sports Center, in Marikina City, Metro Manila, Philippines, March 2, 2021. REUTERS/Lisa Marie David

A giant screen shows CCTV state media broadcast of the Chinese President Xi Jinping, at a shopping complex, ahead of the National People's Congress (NPC), in Beijing, China March 1, 2021. REUTERS/Tingshu Wang u000d u000d u000d

A traveller shows his electronic bracelet and its box as Israel introduces them to enforce quarantine amid coronavirus disease (COVID-19) for Israelis who return from abroad in the arrivals terminal of Ben Gurion international airport in Lod, near Tel Aviv, Israel March 1, 2021 REUTERS/ Amir Cohen

Travellers show their electronic bracelets as Israel introduces them to enforce quarantine amid coronavirus disease (COVID-19) for Israelis who return from abroad in the arrival terminal of Ben Gurion international airport in Lod, near Tel Aviv, Israel March 1, 2021 REUTERS/ Amir Cohen

Travellers show their electronic bracelets as Israel introduces them to enforce quarantine amid coronavirus disease (COVID-19) for Israelis who return from abroad in the arrivals terminal of Ben Gurion international airport in Lod, near Tel Aviv, Israel March 1, 2021 REUTERS/ Amir Cohen

Travellers show their electronic bracelets as Israel introduces them to enforce quarantine amid coronavirus disease (COVID-19) for Israelis who return from abroad in the arrival terminal of Ben Gurion international airport in Lod, near Tel Aviv, Israel March 1, 2021 REUTERS/ Amir Cohen

Members of the media shoot pictures and video of travellers showing their electronic bracelets as Israel introduces it to enforce quarantine amid coronavirus disease (COVID-19) for Israelis who return from abroad in the arrival terminal of Ben Gurion international airport in Lod, near Tel Aviv, Israel March 1, 2021 REUTERS/ Amir Cohen

A model wears outfits designed by Clement Picot, a fashion design student, as she takes part in a digital fashion show at the Institut Francais de la Mode as part of the Women's Fashion Week in Paris, France, February 20, 2021. Picture taken February 20, 2021. REUTERS/Benoit Tessier

A model wears outfits designed by Clement Picot, a fashion design student, as she takes part in a digital fashion show at the Institut Francais de la Mode as part of the Women's Fashion Week in Paris, France, February 20, 2021. Picture taken February 20, 2021. REUTERS/Benoit Tessier

Model wear outfits designed by Clement Picot, a fashion design student, as they take part in a digital fashion show at the Institut Francais de la Mode as part of the Women's Fashion Week in Paris, France, February 20, 2021. Picture taken February 20, 2021. REUTERS/Benoit Tessier

Clement Picot, a fashion design student, works near outfits backstage during a digital fashion show at the Institut Francais de la Mode as part of the Women's Fashion Week in Paris, France, February 20, 2021. Picture taken February 20, 2021. REUTERS/Benoit Tessier

Model wear outfits designed by Clement Picot, a fashion design student, as they take part in a digital fashion show at the Institut Francais de la Mode as part of the Women's Fashion Week in Paris, France, February 20, 2021. Picture taken February 20, 2021. REUTERS/Benoit Tessier

Clement Picot, a fashion design student, works backstage during a digital fashion show at the Institut Francais de la Mode as part of the Women's Fashion Week in Paris, France, February 20, 2021. Picture taken February 20, 2021. REUTERS/Benoit Tessier

A model wears outfits designed by Clement Picot, a fashion design student, as she takes part in a digital fashion show at the Institut Francais de la Mode as part of the Women's Fashion Week in Paris, France, February 20, 2021. Picture taken February 20, 2021. REUTERS/Benoit Tessier

Clement Picot, a fashion design student, works near outfits backstage during a digital fashion show at the Institut Francais de la Mode as part of the Women's Fashion Week in Paris, France, February 20, 2021. Picture taken February 20, 2021. REUTERS/Benoit Tessier

A model wears outfits designed by Clement Picot, a fashion design student, as she takes part in a digital fashion show at the Institut Francais de la Mode as part of the Women's Fashion Week in Paris, France, February 20, 2021. Picture taken February 20, 2021. REUTERS/Benoit Tessier

Models wait backstage before a presentation of Clement Picot, a fashion design student, during a digital fashion show at the Institut Francais de la Mode as part of the Women's Fashion Week in Paris, France, February 20, 2021. Picture taken February 20, 2021. REUTERS/Benoit Tessier

Clement Picot, a fashion design student, works near outfits backstage during a digital fashion show at the Institut Francais de la Mode as part of the Women's Fashion Week in Paris, France, February 20, 2021. Picture taken February 20, 2021. REUTERS/Benoit Tessier

A model dons earrings backstage before a presentation of Clement Picot, a fashion design student, in a digital fashion show at the Institut Francais de la Mode as part of the Women's Fashion Week in Paris, France, February 20, 2021. Picture taken February 20, 2021. REUTERS/Benoit Tessier

A fashion design student takes a picture backstage during a digital fashion show at the Institut Francais de la Mode as part of the Women's Fashion Week in Paris, France, February 20, 2021. Picture taken February 20, 2021. REUTERS/Benoit Tessier

A model gets hair and makeup done backstage before a presentation of Clement Picot, a fashion design student, during a digital fashion show at the Institut Francais de la Mode as part of the Women's Fashion Week in Paris, France, February 20, 2021. Picture taken February 20, 2021. REUTERS/Benoit Tessier

A model looks out a window backstage before a presentation of Clement Picot, a fashion design student, in a digital fashion show at the Institut Francais de la Mode as part of the Women's Fashion Week in Paris, France, February 20, 2021. Picture taken February 20, 2021. REUTERS/Benoit Tessier

Outfits by a fashion design student hang backstage during a digital fashion show at the Institut Francais de la Mode as part of the Women's Fashion Week in Paris, France, February 20, 2021. Picture taken February 20, 2021. REUTERS/Benoit Tessier

Fashion design students make an adjustments to a model's outfit backstage during a digital fashion show at the Institut Francais de la Mode as part of the Women's Fashion Week in Paris, France, February 20, 2021. Picture taken February 20, 2021. REUTERS/Benoit Tessier

Clement Picot, a fashion design student, is pictured backstage during a digital fashion show at the Institut Francais de la Mode as part of the Women's Fashion Week in Paris, France, February 20, 2021. Picture taken February 20, 2021. REUTERS/Benoit Tessier

A model waits backstage before a presentation of Clement Picot, a fashion design student, during a digital fashion show at the Institut Francais de la Mode as part of the Women's Fashion Week in Paris, France, February 20, 2021. Picture taken February 20, 2021. REUTERS/Benoit Tessier