Revelers dance outside bars in London on Saturday, as restrictions are further eased during the COVID-19 pandemic. Photo: AFP

A surge in coronavirus cases sapped the fun out of July 4 celebrations in the US as the pandemic also accelerated through neighboring Mexico, the rest of Latin America and South Africa.

Even Europe, which has largely been celebrating reopening, saw some setbacks, with authorities placing 200,000 people back under lockdown in Spain after a spike in infections that underlined how easily hard-won progress can be reversed.

The US remains by far the world's hardest-hit country, logging a further 43,000 cases Saturday that brought its total number of infections to more than 2.8 million, with nearly 130,000 deaths.

The spiraling caseload cast a pall over traditional Independence Day celebrations, with beaches closed and the National Mall in Washington, usually crowded with spectators ready for fireworks, near deserted.

As the virus continues its relentless march around the world, Latin America is also grappling with rising cases. 

Mexico's toll crossed 30,000 on Saturday, propelling it past France to become the fifth-hardest-hit country in the world.

And Brazil, which has defiantly opened bars and restaurants in Rio de Janeiro, notched up nearly 40,000 new cases and more than a thousand deaths, keeping it in second place behind the US.

Across the Atlantic, South Africa reported more than 10,000 new infections Saturday, its highest ever daily jump. 

Britain, was decidedly more cheerful on Saturday as local pubs reopened for the first time since late March.

"It feels amazing," said Leo Richard Bill, a soldier, after getting through the door of one of London's buzziest restaurants on the River Thames's popular south bank.

"It's been what, like three months since... me and everyone else haven't been able to get outside and have a good time. So yeah, it feels good to get amongst it," he said.

Britain's Prince William got into the spirit by having his picture taken sipping a glass of cider and dutifully using hand sanitizer from a wall-mounted dispenser.

AFP