Chander Gawri shows the at-home COVID-19 test given to all international arrivals before he boards a shuttle which will take him to a quarantine hotel, as part of Canada's new measures against the coronavirus disease (COVID-19), at Toronto Pearson International Airport in Mississauga, Ontario, Canada February 24, 2021. REUTERS/Carlos Osorio

A healthcare worker shows one of the at-home COVID-19 tests given to passengers arriving in Canada, as part of the country's new measures against the coronavirus disease (COVID-19), at Toronto Pearson International Airport in Mississauga, Ontario, Canada February 24, 2021. REUTERS/Carlos Osorio

A passenger arriving in Canada receives an at-home COVID-19 test as part of Canada's new measures against the coronavirus disease (COVID-19, at Toronto Pearson International Airport in Mississauga, Ontario, Canada February 24, 2021. REUTERS/Carlos Osorio

COVID-19 at-home tests sit on a table to be given to passengers arriving in Canada, as part of the country's new measures against the coronavirus disease (COVID-19), at Toronto Pearson International Airport in Mississauga, Ontario, Canada February 24, 2021. REUTERS/Carlos Osorio

Travellers from an international flight are directed to the COVID-19 testing area as part of Canada's new measures against the coronavirus disease (COVID-19), at Toronto Pearson International Airport in Mississauga, Ontario, Canada February 24, 2021. REUTERS/Carlos Osorio

Two immigrants from Mexico arrive by foot as travellers arriving from the United States enter a tent erected to perform the coronavirus disease (COVID-19) molecular test at one of five initial entry points, at the Champlain-St. Bernard de Lacolle Border Crossing in St. Bernard de Lacolle, Quebec, Canada February 24, 2021. REUTERS/Christinne Muschi

Two immigrants from Mexico arrive by foot as travellers arriving from the United States enter a tent erected to perform the coronavirus disease (COVID-19) molecular test at one of five initial entry points, at the Champlain-St. Bernard de Lacolle Border Crossing in St. Bernard de Lacolle, Quebec, Canada February 24, 2021. REUTERS/Christinne Muschi

Two immigrants from Mexico arrive by foot as travellers arriving from the United States enter a tent erected to perform the coronavirus disease (COVID-19) molecular test at one of five initial entry points, at the Champlain-St. Bernard de Lacolle Border Crossing in St. Bernard de Lacolle, Quebec, Canada February 24, 2021. REUTERS/Christinne Muschi

Two immigrants from Mexico arrive by foot as travellers arriving from the United States enter a tent erected to perform the coronavirus disease (COVID-19) molecular test at one of five initial entry points, at the Champlain-St. Bernard de Lacolle Border Crossing in St. Bernard de Lacolle, Quebec, Canada February 24, 2021. REUTERS/Christinne Muschi

Travellers arriving from the United States enter a tent erected to perform the coronavirus disease (COVID-19) molecular test at one of five initial entry points, at the Champlain-St. Bernard de Lacolle Border Crossing in St. Bernard de Lacolle, Quebec, Canada February 24, 2021. REUTERS/Christinne Muschi

Travellers arriving from the United States enter a tent erected to perform the coronavirus disease (COVID-19) molecular test at one of five initial entry points, at the Champlain-St. Bernard de Lacolle Border Crossing in St. Bernard de Lacolle, Quebec, Canada February 24, 2021. REUTERS/Christinne Muschi

Travellers arriving from the United States enter a tent erected to perform the coronavirus disease (COVID-19) molecular test at one of five initial entry points, at the Champlain-St. Bernard de Lacolle Border Crossing in St. Bernard de Lacolle, Quebec, Canada February 24, 2021. REUTERS/Christinne Muschi

Travellers arriving from the United States enter a tent erected to perform the coronavirus disease (COVID-19) molecular test at one of five initial entry points, at the Champlain-St. Bernard de Lacolle Border Crossing in St. Bernard de Lacolle, Quebec, Canada February 24, 2021. REUTERS/Christinne Muschi

Children wait to take an electric autonomous bus which is driven in autopilot mode during a month test phase with passengers in Malaga, Spain February 24, 2021. REUTERS/Jon Nazca

Avanza bus company technicians and passengers are seen in the mirror of an electric autonomous bus which is driven in the autopilot mode during a month test phase with passengers in Malaga, Spain February 24, 2021. REUTERS/Jon Nazca

Passengers sit in an electric autonomous bus which is driven in autopilot mode during a month test phase with passengers in Malaga, Spain February 24, 2021. REUTERS/Jon Nazca

Passengers sit in an electric autonomous bus which is driven in autopilot mode past the Pompidou museum, during a month test phase with passengers in Malaga, Spain February 24, 2021. REUTERS/Jon Nazca

People wait to take an electric autonomous bus which is driven in autopilot mode during a month test phase with passengers in Malaga, Spain February 24, 2021. REUTERS/Jon Nazca

People wait to take an electric autonomous bus which is driven in autopilot mode during a month test phase with passengers in Malaga, Spain February 24, 2021. REUTERS/Jon Nazca

Children wait to take an electric autonomous bus which is driven in autopilot mode during a month test phase with passengers in Malaga, Spain February 24, 2021. REUTERS/Jon Nazca

Avanza bus company driver Cristobal Maldonado, 60, oversees an electric autonomous bus in autopilot mode during a month test phase with passengers in Malaga, Spain February 24, 2021. REUTERS/Jon Nazca

Avanza bus company driver Cristobal Maldonado, 60, oversees an electric autonomous bus in autopilot mode during a month test phase with passengers in Malaga, Spain February 24, 2021. REUTERS/Jon Nazca

Avanza bus company driver Cristobal Maldonado, 60, oversees an electric autonomous bus in autopilot mode during a month test phase with passengers in Malaga, Spain February 24, 2021. REUTERS/Jon Nazca

Avanza bus company driver Cristobal Maldonado, 60, oversees an electric autonomous bus in autopilot mode during a month test phase with passengers in Malaga, Spain February 24, 2021. REUTERS/Jon Nazca

Avanza bus company driver Cristobal Maldonado, 60, oversees an electric autonomous bus in autopilot mode during a month test phase with passengers in Malaga, Spain February 24, 2021. REUTERS/Jon Nazca

Avanza bus company driver Cristobal Maldonado, 60, oversees an electric autonomous bus in autopilot mode during a month test phase with passengers in Malaga, Spain February 24, 2021. REUTERS/Jon Nazca

Avanza bus company driver Cristobal Maldonado, 60, oversees an electric autonomous bus in autopilot mode during a month test phase with passengers in Malaga, Spain February 24, 2021. REUTERS/Jon Nazca

An electric autonomous bus travels in autopilot mode along a street during a month test phase with passengers in Malaga, Spain February 24, 2021. REUTERS/Jon Nazca

An electric autonomous bus travels in autopilot mode along a street during a month test phase with passengers in Malaga, Spain February 24, 2021. REUTERS/Jon Nazca

A medical worker holds a test tube after administering a nasal swab to a patient at a coronavirus disease (COVID-19) testing center installed inside in the Kursaal concert hall in Dunkirk as the government eyes new measures to limit the spread of COVID-19 in the region, France, February 24, 2021. REUTERS/ Pascal Rossignol

A medical worker prepares to administer a nasal swab to a patient at a coronavirus disease (COVID-19) testing center installed inside in the Kursaal concert hall in Dunkirk as the government eyes new measures to limit the spread of COVID-19 in the region, France, February 24, 2021. REUTERS/ Pascal Rossignol

A medical worker holds a test tube after administering a nasal swab to a patient at a coronavirus disease (COVID-19) testing center installed inside in the Kursaal concert hall in Dunkirk as the government eyes new measures to limit the spread of COVID-19 in the region, France, February 24, 2021. REUTERS/ Pascal Rossignol

A medical worker walks between booths at a coronavirus disease (COVID-19) testing center installed inside in the Kursaal concert hall in Dunkirk as the government eyes new measures to limit the spread of COVID-19 in the region, France, February 24, 2021. REUTERS/ Pascal Rossignol

Patients wait for their test results at a coronavirus disease (COVID-19) testing center installed inside in the Kursaal concert hall in Dunkirk as the government eyes new measures to limit the spread of COVID-19 in the region, France, February 24, 2021. REUTERS/ Pascal Rossignol

Medical workers welcome patients at a coronavirus disease (COVID-19) testing center installed inside in the Kursaal concert hall in Dunkirk as the government eyes new measures to limit the spread of COVID-19 in the region, France, February 24, 2021. REUTERS/ Pascal Rossignol

A medical worker prepares to administer a nasal swab to a patient at a coronavirus disease (COVID-19) testing center installed inside in the Kursaal concert hall in Dunkirk as the government eyes new measures to limit the spread of COVID-19 in the region, France, February 24, 2021. REUTERS/ Pascal Rossignol

New "filtering and decontaminating" mask designed by French start-up BioSerenity are tested at the INSERM research center of Lille University Medical School, amid the spread of the coronavirus disease (COVID-19) in France, February 22, 2021. Picture taken, February 22, 2021. REUTERS/Pascal Rossignol

New "filtering and decontaminating" mask designed by French start-up BioSerenity are tested at the INSERM research center of Lille University Medical School, amid the spread of the coronavirus disease (COVID-19) in France, February 22, 2021. Picture taken, February 22, 2021. REUTERS/Pascal Rossignol

A fan wearing a cap featuring Indian cricket players waits to enter the newly named Narendra Modi Stadium, previously known as Motera Stadium, before the start of the third test match between India and England, in Ahmedabad, India, February 24, 2021. REUTERS/Amit Dave

Fans take selfie with a man whose body is painted in the colours of India and England as they wait to enter the newly named Narendra Modi Stadium, previously known as Motera Stadium, before the start of the third test match between India and England, amidst the spread of the coronavirus disease (COVID-19), in Ahmedabad, India, February 24, 2021. REUTERS/Amit Dave TPX IMAGES OF THE DAY

A man with his body painted in the colours of India and England waves a flag as fans wait to enter the newly named Narendra Modi Stadium, previously known as Motera Stadium, before the start of the third test match between India and England, amidst the spread of the coronavirus disease (COVID-19), in Ahmedabad, India, February 24, 2021. REUTERS/Amit Dave

Fans react as they wait to enter the newly named Narendra Modi Stadium, previously known as Motera stadium, before the start of the third test match between India and England, amidst the spread of the coronavirus disease (COVID-19), in Ahmedabad, India, February 24, 2021. REUTERS/Amit Dave

Fans holds placards featuring India's cricket captain Virat Kohli as they wait to enter the newly named Narendra Modi Stadium, previously known as Motera Stadium, before the start of the third test match between India and England, amidst the spread of the coronavirus disease (COVID-19), in Ahmedabad, India, February 24, 2021. REUTERS/Amit Dave

Fans react as they wait to enter the newly named Narendra Modi Stadium, previously known as Motera stadium, before the start of the third test match between India and England, amidst the spread of the coronavirus disease (COVID-19), in Ahmedabad, India, February 24, 2021. REUTERS/Amit Dave

Workers install a hoarding renaming the world's largest cricket stadium, previously known as the?Motera Stadium, after Prime Minister Narendra Modi, as fans wait to enter before the start of the third test match between India and England in Ahmedabad, India, February 24, 2021. REUTERS/Amit Dave

Workers install a hoarding renaming the world's largest cricket stadium after Prime Minister Narendra Modi, as fans wait to enter before the start of the third test match between India and England in Ahmedabad, India, February 24, 2021. REUTERS/Amit Dave

British Prime Minister Boris Johnson is seen at the gym which is used as a makeshift testing centre for the students, due to the coronavirus disease (COVID-19) outbreak, during his visit to the Sedgehill School, in London, Britain February 23, 2021. Jack Hill/Pool via REUTERS

British Prime Minister Boris Johnson is seen at the gym which is used as a makeshift testing centre for the students, due to the coronavirus disease (COVID-19) outbreak, during his visit to the Sedgehill School, in London, Britain February 23, 2021. Jack Hill/Pool via REUTERS

British Prime Minister Boris Johnson speaks at the gym which is used as a makeshift testing centre for the students, due to the coronavirus disease (COVID-19) outbreak, during his visit to the Sedgehill School, in London, Britain February 23, 2021. Jack Hill/Pool via REUTERS

British Prime Minister Boris Johnson is seen at the gym which is used as a makeshift testing centre for the students, due to the coronavirus disease (COVID-19) outbreak, during his visit to the Sedgehill School, in London, Britain February 23, 2021. Jack Hill/Pool via REUTERS

British Prime Minister Boris Johnson is seen at the gym which is used as a makeshift testing centre for the students, due to the coronavirus disease (COVID-19) outbreak, during his visit to the Sedgehill School, in London, Britain February 23, 2021. Jack Hill/Pool via REUTERS

A forensic pathologist takes a swab from a body for a coronavirus disease (COVID-19) test at the Institute for Forensic Medicine of Belgrade's Medical Faculty, in Belgrade, Serbia, February 22, 2021. Picture taken February 22, 2021. REUTERS/Marko Djurica

A scientist displays a smartphone showing curve indicating a COVID-19 test positive result during an interview with Reuters about a project called CorDial-1 for rapid COVID tests via smartphones, at a CNRS research laboratory in Villeneuve-d'Ascq, France, February 11, 2021. Picture taken February 11, 2021. REUTERS/Pascal Rossignol

Researcher Sabine Szunerits, Professor in Chemistry at the University Lille 1, surrounded Rabah Boukherroub, Research Director Group Leader at the Institute of Electronics, Microelectronics and Nanotechnology at the University of Lille, and Professor David Devos, displays a smartphone showing curve indicating a COVID-19 test positive result during an interview with Reuters about a project called CorDial-1 for rapid COVID tests via smartphones, at the CNRS in Villeneuve-d'Ascq, France, February 11, 2021. Picture taken February 11, 2021. REUTERS/Pascal Rossignol

Researcher Sabine Szunerits, Professor in Chemistry at the University Lille 1, displays a smartphone showing curve indicating a COVID-19 test positive result during an interview with Reuters about a project called CorDial-1 for rapid COVID tests via smartphones, at the CNRS in Villeneuve-d'Ascq, France, February 11, 2021. Picture taken February 11, 2021. REUTERS/Pascal Rossignol

A healthcare worker in personal protective equipment (PPE) collects a swab sample from a resident during a testing campaign for the coronavirus disease (COVID-19), in Mumbai, India, February 23, 2021. REUTERS/Francis Mascarenhas

A healthcare worker in personal protective equipment (PPE) collects a swab sample from a resident during a testing campaign for the coronavirus disease (COVID-19), in Mumbai, India, February 23, 2021. REUTERS/Francis Mascarenhas

A sign for the coronavirus disease (COVID-19) test collection centre is seen at Vancouver International Airport in Richmond, British Columbia, Canada February 22, 2021. REUTERS/Jennifer Gauthier

A sign for the coronavirus disease (COVID-19) test collection centre is seen at Vancouver International Airport in Richmond, British Columbia, Canada February 22, 2021. REUTERS/Jennifer Gauthier

Employees of the Public Health Agency of Canada stand outside a tent erected to perform the coronavirus disease (COVID-19) molecular test at one of five initial entry points at the Douglas border crossing in Surrey, British Columbia, Canada February 22, 2021. REUTERS/Jennifer Gauthier