A staff member at a coffee shop reviews a digital vaccination certificate on the day the Canary Islands government imposed stricter rules to control a surge in coronavirus (COVID-19) cases, on the island of Tenerife, Spain, July 26, 2021. REUTERS/Borja Suarez

People walk down a street in Santa Cruz De Tenerife on the day the Canary Islands government imposed stricter rules to control a surge in coronavirus disease (COVID-19) cases, on the island of Tenerife, Spain, July 26, 2021. REUTERS/Borja Suarez

Two tourists walk without face masks in La Laguna on the day the Canary Islands government imposed stricter rules to control a surge in coronavirus disease (COVID-19) cases, on the island of Tenerife, Spain, July 26, 2021. REUTERS/Borja Suarez

A restaurant staffer reviews a digital vaccination certificate on the day the Canary Islands government imposed stricter rules in an attempt to control a surge in coronavirus (COVID-19) cases in Tenerife, Spain, July 26, 2021. REUTERS/Borja Suarez

A restaurant staffer reviews a digital vaccination certificate on the day the Canary Islands government imposed stricter rules in an attempt to control a surge in coronavirus (COVID-19) cases in Tenerife, Spain, July 26, 2021. REUTERS/Borja Suarez

A woman downloads the European digital vaccination certificate to enter a cafeteria on the day the Canary Islands government imposed stricter rules in an attempt to control a surge in coronavirus (COVID-19) cases in Tenerife, Spain, July 26, 2021. REUTERS/Borja Suarez

People lay on sunbeds at the Tropicana beach bar in Paradise beach, as Greece banned music in restaurants and bars and imposed a nighttime curfew on the island of Mykonos, Greece, July 18, 2021. REUTERS/Louiza Vradi

People stand on the beach in front of Mykonos' windmills as Greece banned music in restaurants and bars and imposed a nighttime curfew on the island of Mykonos, Greece, July 18, 2021. REUTERS/Louiza Vradi

A worker makes his way in Little Venice, as Greece banned music in restaurants and bars and imposed a nighttime curfew on the island of Mykonos, Greece, July 18, 2021. REUTERS/Louiza Vradi

View of Mykonos' windmills through a cafe in Little Venice, as Greece banned music in restaurants and bars and imposed a nighttime curfew on the island of Mykonos, Greece, July 18, 2021. REUTERS/Louiza Vradi

A girl sits on a bench, as Greece banned music in restaurants and bars and imposed a nighttime curfew on the island of Mykonos, Greece, July 18, 2021. REUTERS/Louiza Vradi

A man carries goods in a crate in Little Venice, as Greece banned music in restaurants and bars and imposed a nighttime curfew on the island of Mykonos, Greece, July 18, 2021. REUTERS/Louiza Vradi

Tourists Nora Kismoune and Christelle Girod sit at a cafe in Little Venice as Greece banned music in restaurants and bars and imposed a nighttime curfew on the island of Mykonos, Greece, July 18, 2021. REUTERS/Louiza Vradi

People enjoy the view in a cafe in Little Venice as Greece banned music in restaurants and bars and imposed a nighttime curfew on the island of Mykonos, Greece, July 18, 2021. REUTERS/Louiza Vradi

A woman makes her way in Little Venice as Greece banned music in restaurants and bars and imposed a nighttime curfew on the island of Mykonos, Greece, July 18, 2021. REUTERS/Louiza Vradi

Tourists take pictures in Little Venice as Greece banned music in restaurants and bars and imposed a nighttime curfew on the island of Mykonos, Greece, July 18, 2021. REUTERS/Louiza Vradi

A woman walks in an alley, as Greece banned music in restaurants and bars and imposed a nighttime curfew on the island of Mykonos, Greece, July 18, 2021. REUTERS/Louiza Vradi

Workers paint a church in Mykonos town as Greece banned music in restaurants and bars and imposed a nighttime curfew on the island of Mykonos Greece, July 18, 2021. REUTERS/Louiza Vradi

View of an empty alley in Mykonos town, as Greece banned music in restaurants and bars and imposed a nighttime curfew on the island of Mykonos Greece, July 18, 2021. REUTERS/Louiza Vradi

A couple walks in front of Mykonos' windmills as Greece banned music in restaurants and bars and imposed a nighttime curfew on the island of Mykonos Greece, July 18, 2021. REUTERS/Louiza Vradi

A cruise ship is moored in Mykonos port with Little Venice in the foreground as Greece banned music in restaurants and bars and imposed a nighttime curfew on the island of Mykonos Greece, July 18, 2021. REUTERS/Louiza Vradi

A couple stands in front of Mykonos' windmills as Greece banned music in restaurants and bars and imposed a nighttime curfew on the island of Mykonos Greece, July 18, 2021. REUTERS/Louiza Vradi

People make their way in an alley as Greece banned music in restaurants and bars and imposed a nighttime curfew on the island of Mykonos, Greece, July 18, 2021. REUTERS/Louiza Vradi

People sit in front of Mykonos' windmills as Greece banned music in restaurants and bars and imposed a nighttime curfew on the island of Mykonos, Greece, July 18, 2021. REUTERS/Louiza Vradi

People walk in an alley as Greece banned music in restaurants and bars and imposed a nighttime curfew on the island of Mykonos, Greece, July 17, 2021. Picture taken July 17, 2021. REUTERS/Louiza Vradi

People enjoy their time in a bar as Greece banned music in restaurants and bars and imposed a nighttime curfew on the island of Mykonos Greece, July 17, 2021. Picture taken July 17, 2021. REUTERS/Louiza Vradi

Tourists are seen in Mykonos town as Greece banned music in restaurants and bars and imposed a nighttime curfew on Mykonos island, in Mykonos Greece, July 18, 2021. REUTERS/Louiza Vradi

Tourists are seen in front of closed shops and restaurants in Mykonos town as Greece banned music in restaurants and bars and imposed a nighttime curfew on Mykonos island, in Mykonos Greece, July 18, 2021. REUTERS/Louiza Vradi

Empty bars are seen in Little Venice as Greece banned music in restaurants and bars and imposed a nighttime curfew on Mykonos island, in Mykonos Greece, July 18, 2021. REUTERS/Louiza Vradi

A shop owner prepares to close his shot in Mykonos town as Greece banned music in restaurants and bars and imposed a nighttime curfew on Mykonos island, in Mykonos Greece, July 17, 2021. REUTERS/Louiza Vradi

Tourists are seen in front of closed shops and restaurants in Mykonos town as Greece banned music in restaurants and bars and imposed a nighttime curfew on Mykonos island, in Mykonos Greece, July 18, 2021. REUTERS/Louiza Vradi

Britain's Prime Minister Boris Johnson leaves after giving an update on relaxing restrictions imposed on the country during the coronavirus disease (COVID-19) pandemic from behind a lectern at a news conference inside the Downing Street Briefing Room in London, Britain July 12, 2021. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson gives an update on relaxing restrictions imposed on the country during the coronavirus disease (COVID-19) pandemic from behind a lectern at a news conference inside the Downing Street Briefing Room in London, Britain July 12, 2021. Daniel Leal-Olivas/Pool via REUTERS

Britain's Chief Medical Officer for England Chris Whitty, Britain's Prime Minister Boris Johnson and Britain's Chief Scientific Adviser Patrick Vallance give an update on relaxing restrictions imposed on the country during the coronavirus disease (COVID-19) pandemic at a news conference inside the Downing Street Briefing Room in London, Britain July 12, 2021. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson looks on at a news conference as he gives an update on relaxing restrictions imposed on the country during the coronavirus disease (COVID-19) pandemic inside the Downing Street Briefing Room in London, Britain July 12, 2021. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson looks on at a news conference as he gives an update on relaxing restrictions imposed on the country during the coronavirus disease (COVID-19) pandemic inside the Downing Street Briefing Room in London, Britain July 12, 2021. Daniel Leal-Olivas/Pool via REUTERS

Britain's Chief Scientific Adviser Patrick Vallance gives an update on relaxing restrictions imposed on the country during the coronavirus disease (COVID-19) pandemic at a news conference inside the Downing Street Briefing Room in London, Britain July 12, 2021. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson gives an update on relaxing restrictions imposed on the country during the coronavirus disease (COVID-19) pandemic at a news conference inside the Downing Street Briefing Room in London, Britain July 12, 2021. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson reacts at a news conference as he gives an update on relaxing restrictions imposed on the country during the coronavirus disease (COVID-19) pandemic inside the Downing Street Briefing Room in London, Britain July 12, 2021. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson reacts at a news conference as he gives an update on relaxing restrictions imposed on the country during the coronavirus disease (COVID-19) pandemic inside the Downing Street Briefing Room in London, Britain July 12, 2021. Daniel Leal-Olivas/Pool via REUTERS

Britain's Chief Medical Officer for England Chris Whitty looks on at a news conference as he gives an update on relaxing restrictions imposed on the country during the coronavirus disease (COVID-19) pandemic inside the Downing Street Briefing Room in London, Britain July 12, 2021. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson looks on at a news conference as he gives an update on relaxing restrictions imposed on the country during the coronavirus disease (COVID-19) pandemic inside the Downing Street Briefing Room in London, Britain July 12, 2021. Daniel Leal-Olivas/Pool via REUTERS

Britain's Chief Medical Officer for England Chris Whitty explains a pictogram on a slide as he gives an gives an update on relaxing restrictions imposed on the country during the coronavirus disease (COVID-19) pandemic at a news conference inside the Downing Street Briefing Room in London, Britain July 12, 2021. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson looks on at a news conference as he gives an update on relaxing restrictions imposed on the country during the coronavirus disease (COVID-19) pandemic inside the Downing Street Briefing Room in London, Britain July 12, 2021. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson gives an update on relaxing restrictions imposed on the country during the coronavirus disease (COVID-19) pandemic at a news conference inside the Downing Street Briefing Room in London, Britain July 12, 2021. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson gives an update on relaxing restrictions imposed on the country during the coronavirus disease (COVID-19) pandemic at a news conference inside the Downing Street Briefing Room in London, Britain July 12, 2021. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson gives an update on relaxing restrictions imposed on the country during the coronavirus disease (COVID-19) pandemic at a news conference inside the Downing Street Briefing Room in London, Britain July 12, 2021. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson gives an update on relaxing restrictions imposed on the country during the coronavirus disease (COVID-19) pandemic at a news conference inside the Downing Street Briefing Room in London, Britain July 12, 2021. Daniel Leal-Olivas/Pool via REUTERS

Britain's Prime Minister Boris Johnson gives an update on relaxing restrictions imposed on the country during the coronavirus disease (COVID-19) pandemic at a news conference inside the Downing Street Briefing Room in London, Britain July 12, 2021. Daniel Leal-Olivas/Pool via REUTERS

A vendor waits for customers at an almost empty road which is usually crowded with people, as lockdown and travel restrictions are imposed to curb the spread of the coronavirus disease (COVID-19) in Bangkok, Thailand, July 12, 2021. REUTERS/Soe Zeya Tun

A man rides his bike on an almost empty road which is usually crowded with people, as lockdown and travel restrictions are imposed to curb the spread of the coronavirus disease (COVID-19) in Bangkok, Thailand, July 12, 2021. REUTERS/Soe Zeya Tun

A man uses his phone at an almost empty road which is usually crowded with people, as lockdown and travel restrictions are imposed to curb the spread of the coronavirus disease (COVID-19) in Bangkok, Thailand, July 12, 2021. REUTERS/Soe Zeya Tun

A man uses his phone at an almost empty road which is usually crowded with people, as lockdown and travel restrictions are imposed to curb the spread of the coronavirus disease (COVID-19) in Bangkok, Thailand, July 12, 2021. REUTERS/Soe Zeya Tun

A man waits for customers in-front of his shop at an almost empty road which is usually crowded with people, as lockdown and travel restrictions are imposed to curb the spread of the coronavirus disease (COVID-19) in Bangkok, Thailand, July 12, 2021. REUTERS/Soe Zeya Tun

A closed shopping mall is seen as lockdown and travel restrictions are imposed to curb the spread of the coronavirus disease (COVID-19) in Bangkok, Thailand, July 12, 2021. REUTERS/Soe Zeya Tun

A closed shopping mall is seen as lockdown and travel restrictions are imposed to curb the spread of the coronavirus disease (COVID-19) in Bangkok, Thailand, July 12, 2021. REUTERS/Soe Zeya Tun

A closed shopping mall is seen as lockdown and travel restrictions are imposed to curb the spread of the coronavirus disease (COVID-19) in Bangkok, Thailand, July 12, 2021. REUTERS/Soe Zeya Tun

The AirAsia counter is closed as lockdown and travel restrictions are imposed to curb the spread of the coronavirus disease (COVID-19) at Don Muang Airport in Bangkok, Thailand, July 12, 2021. REUTERS/Soe Zeya Tun

The AirAsia counter is closed as lockdown and travel restrictions are imposed to curb the spread of the coronavirus disease (COVID-19) at Don Muang Airport in Bangkok, Thailand, July 12, 2021. REUTERS/Soe Zeya Tun

The AirAsia counter is closed as lockdown and travel restrictions are imposed to curb the spread of the coronavirus disease (COVID-19) at Don Muang Airport in Bangkok, Thailand, July 12, 2021. REUTERS/Soe Zeya Tun