In this image from a scanning electron microscope, the new coronavirus is in orange.
The coronavirus pandemic has found fresh legs around the world, as confirmed deaths pass 600,000 and countries from Australia to the US to South Africa to India struggle to contain a surge of new infections.
Hong Kong issued tougher new rules on wearing face masks, Spain closed overcrowded beaches and Germany reported another outbreak at a slaughterhouse.
Pope Francis said "the pandemic is showing no sign of stopping" and urged compassion for those whose suffering during the outbreak has been worsened by conflicts.
The World Health Organisation said 259,848 new infections were reported on Saturday, its highest one-day tally yet.
Cases in the Australian state of Victoria rose again on Sunday, prompting a move to make masks mandatory in metropolitan Melbourne and the nearby district of Mitchell for people who leave their homes for exercise or to purchase essential goods.
Victoria Premier Daniel Andrews said those who fail to wear a mask will be fined A$200.
"There's no vaccine to this wildly infectious virus and it's a simple thing, but it's about changing habits, it's about becoming a simple part of your routine," Andrews said.
While the US leads global infections, South Africa now ranks as the fifth worst-hit country in the pandemic with more than 350,000 cases, or around half of all those confirmed on the continent.
Its struggles are a sign of trouble to come for nations with even fewer health care resources.
India, which has now confirmed more than 1 million infections, on Sunday reported a 24-hour record of 38,902 new cases.
In Europe, where infections are far below their peak but local outbreaks are causing concern, leaders of the 27-nation European Union haggled for a third day in Brussels over a proposed 1.85 trillion-euro ($2.1 trillion) EU budget and coronavirus recovery fund.
German Chancellor Angela Merkel said there is "a lot of goodwill, but there are also a lot of positions" in the talks, which have laid bare divisions about how the countries hit hardest by the pandemic, such as Italy and Spain, should be helped. She said the talks, which were initially scheduled to end on Saturday, could still end without a deal.
As scientists around the world race to find a vaccine to halt the pandemic, Russia's ambassador to Britain on Sunday rejected allegations by the United States, Britain and China that his country's intelligence services have sought to steal information about vaccine efforts.
"I don't believe in this story at all, there is no sense in it," Ambassador Andrei Kelin said when asked in a BBC interview about the allegations.
"I learned about their [the hackers'] existence from British media. In this world, to attribute any kind of computer hackers to any country, it is impossible."
Confirmed global virus deaths have risen to nearly 603,000, according to data compiled by Johns Hopkins. The United States tops the list with over 140,000, followed by more than 78,000 in Brazil. Europe as a continent has seen about 200,000 deaths.
The number of confirmed infections worldwide has passed 14.2 million, with 3.7 million in the United States and more than 2 million in Brazil. Experts believe the pandemic's true toll around the world is much higher because of testing shortages and data collection issues.
Infections have been soaring in US states such as Florida, Texas, Arizona, with many blaming a haphazard, partisan approach to lifting lockdowns as well as the resistance of some Americans to wearing masks.
Los Angeles Mayor Eric Garcetti said on Sunday that the situation was so dire in his California city that authorities were considering a new stay-at-home order.
Even where the situation has been largely brought under control, new outbreaks are prompting the return of restrictions.
Following a recent surge in cases, Hong Kong made the wearing of masks mandatory in all public places and told non-essential civil servants to work from home. Hong Kong leader Carrie Lam said the situation in the Asian financial hub is "really critical" and that she sees "no sign" that it's under control.
Police in Barcelona have limited access to some of the city's beloved beaches because sunbathers were ignoring social distancing regulations amid a resurgence of coronavirus infections. Authorities in Amsterdam urged people not to visit the city's famous red light district and have closed off some of the historic district's narrow streets because they are too busy.
Slaughterhouses also have featured in outbreaks in the US, Germany and elsewhere. Authorities in northwestern Germany's Vechta county said 66 workers at a chicken slaughterhouse tested positive, though most appeared to have been infected in their free time. An earlier outbreak at a slaughterhouse in western Germany infected over 1400 and prompted a partial lockdown.
Speaking on Sunday from his window overlooking St Peter's Square, Pope Francis renewed his appeal for an immediate worldwide cease-fire that he said "will permit the peace and security indispensable to supplying the necessary humanitarian assistance".