China reported its highest daily number of new coronavirus cases in months on Sunday with parts of Beijing still under lockdown, offering a second wave warning to the rest of the world as the pandemic rages in South America.
The shock resurgence in domestic infections has rattled China, where the disease emerged late last year but had largely been tamed through severe restrictions on movement that were later emulated across the globe.
It also provides a bleak insight into the difficulties the world will face in conquering COVID-19 -- even as countries in Europe prepare to reopen borders at the beginning of the summer holiday season after an encouraging drop in contagion.
Of the 57 new cases logged by Chinese authorities, 36 were domestic infections in the capital, where a large wholesale food market at the centre of the outbreak has been closed and nearby housing estates put under lockdown.
"People are scared," a fruit and vegetable trader at another local market in central Beijing told AFP.
"The meat sellers have had to close. This disease is really scary," said the man surnamed Sun, adding there were fewer customers than normal.
At least 429,000 people worldwide have died from the respiratory illness, nearly halfway through a year in which countless lives have already been upended as the pandemic ravages the global economy.
The total number of confirmed cases has doubled to 7.7 million in slightly over a month and the disease is now spreading most rapidly in Latin America, where it is threatening healthcare systems and sparking political turmoil.
Brazil now has the second-highest number of virus deaths after the United States, surpassing Britain's toll, and the Chilean health minister resigned on Saturday amid a furore over the country's true number of fatalities.
There is still no treatment for COVID-19, but pharmaceutical group AstraZeneca said it has agreed to supply an alliance of European countries with up to 400 million doses of a possible vaccine.
German government sources told AFP a vaccine could be developed by the end of the year.
Many European nations are further lifting painful lockdowns that have saved lives and forced caseloads down, but have also caused their economies to shrink and caused misery for millions.
After the European Commission urged a relaxation of restrictions, a number of nations are preparing to reopen borders on Monday -- while some like Poland have done so already, with people from other European Union countries allowed to visit.
Germany said it would end land border checks on Monday, and France said it would gradually reopen its borders to non-Schengen countries from July.
Greek Prime Minister Kyriakos Mitsotakis travelled to picturesque Santorini island on Saturday to open his country's tourism season.
"Greece is ready to welcome tourists this summer by putting safety and health as our No. 1 priority," he said in English in front of a spectacular sunset.
Venice sprang back to life Saturday, as hundreds of tourists flocked to the city for the reopening of the iconic Doge's Palace.
"It's a very strong emotion, like the first day of school," said Maria Cristina Gribaudi, who heads the city's Civic Museums Foundation.
In another joyful return to semi-normality, football superstar Lionel Messi took to the pitch again in Spain as Barcelona resumed their La Liga title challenge and thumped Real Mallorca 4-0 in an empty stadium.
Live sport also returned on Saturday to New Zealand, which has gone 22 days without new coronavirus cases, as 20,000 fans watched rugby's Otago Highlanders edge the Waikato Chiefs.
But even in the much-awaited global sporting revival, there are wobbles -- Australian rugby league officials postponed a top-level game on Sunday hours before kick-off due to a coronavirus scare.
The World Health Organization said this week the pandemic is accelerating in Africa. Botswana's capital Gaborone was locked down Saturday after new cases were detected.
And in the US, which has seen the most COVID-19 deaths with over 115,000, more than a dozen states -- including populous Texas and Florida -- reported their highest-ever daily case totals in recent days.
The rise comes as huge anti-racism protests rage across America and the world, with many demonstrators wearing masks to protect against the spread of the virus.