The World Health Organization (WHO) has described scenes of mass crowds gathering to watch the Euro 2020 final as “devastating”.
Wembley stadium in north-west London hosted 60,000 spectators while crowds of people gathered and partied in streets, pubs, and homes across England to watch the match.
But the decision to allow the final to take place with few COVID mitigation measures has drawn huge criticism from experts and officials around the world.
During the game, the WHO’s coronavirus technical lead Maria Van Kerkhove said watching people watching and celebrating with little COVID mitigation measures was “devastating”.
She tweeted: “Am I supposed to be enjoying watching transmission happening in front of my eyes?
It comes as health secretary Sajid Javid confirmed that remaining lockdown restrictions will be lifted in England on 19 July despite cases of the Delta variant of coronavirus continuing to spread rapidly.
The government has argued that the link between infections, hospitalisations and deaths has been sufficiently severed to allow the unlocking due to the speed of the UK’s COVID vaccine programme.
But other nations have been forced to reimpose measures as they battle outbreaks accelerated by the variant while they try to ramp up vaccine efforts.
For weeks, health experts have expressed concerns that the Euro 2020 tournament events would be super-spreaders, especially in Britain and Russia because of the Delta variant.
Watch: Euro 2020: Kane, Maguire and Grealish all break their silence as dust settles on final defeat
Professor Antoine Flahault, a member of the European Advisory Committee on Health Research, told news agency AP: "It is possible, probable even, that regions very little affected in the UK will find themselves infected by supporters returning from London.”
Meanwhile, WHO senior emergency officer Catherine Smallwood warned that crowds mixing during the tournament have contributed to the recent reverse of a steady decline of cases across Europe.
"We need to look much beyond just the stadiums themselves," Smallwood said.
"We need to look at how people get there – are they travelling in large crowded convoys of buses? And when they leave the stadiums, are they going into crowded bars and pubs to watch the matches?"
With COVID restrictions varying from nation to nation, crowd sizes during Euro 2020 ranged from completely full, such as 60,000 at Wembley and in Budapest, to other venues where there have often been around 10-15,000 spectators.
UEFA said it was fully aligned with local health authorities' guidelines at every venue.
German interior minister Horst Seehofer said UEFA's position was "utterly irresponsible".
"I cannot explain why UEFA is not being sensible... I suspect it is due to commercialism," he told a news conference.
Meanwhile, German chancellor Angela Merkel openly criticised Johnson over the number of England fans allowed into Wembley during Euro 2020.
The German chancellor, speaking at a televised joint press conference with Johnson earlier in July, said attendance numbers were a "bit too much" in light of the UK's third wave of coronavirus cases.
The crowds at Germany’s three group stage games in Munich, by comparison, were limited to 13,000 and Merkel said at the Chequers press conference that she had raised her concerns about Wembley with the prime minister.
"I say this with grave concern," she told reporters. "I have also said this to the prime minister.
"We in Germany, as you know, had less people attend games in the Munich stadium but the British government will obviously take its own decision.
"But I am very much concerned whether it is not a bit too much."
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