Australia's second-largest city imposed an overnight curfew on Sunday to halt the spread of coronavirus cases, as South Africa's infection count topped more than half a million.
Six months after the World Health Organization declared a global emergency, the virus has killed more than 680,000 people and infected more than 17.5 million.
Fresh clusters have been reported in countries—such as Australia—that had previously brought their outbreaks under control.
Australia's Victoria state imposed fresh, sweeping restrictions on Sunday, including a curfew in Melbourne for the next six weeks, a ban on weddings, and schools and universities going back online in the coming days.
"Anything short of this will see it drag on for months and months and months," said Victoria leader Daniel Andrews.
Despite a lockdown, Melbourne has continued to report hundreds of new cases daily even as other states in Australia have reported zero or a small number of cases.
Many other parts of the world are struggling with much bigger outbreaks.
With infections and deaths soaring, the UN health agency has warned that the coronavirus pandemic would be lengthy and could lead to "response fatigue."
"WHO continues to assess the global risk level of COVID-19 to be very high," the agency said, adding that the effects of the pandemic "will be felt for decades to come."
Vaccine race
The pandemic has spurred a race for a vaccine with several Chinese companies at the forefront, while Russia has set a target date of September to roll out its own prophylactic.
However, US infectious disease expert Anthony Fauci said it was unlikely his country would use any vaccine developed in either nation.
"I do hope that the Chinese and the Russians are actually testing the vaccine before they are administering the vaccine to anyone," he said.
As part of its "Operation Warp Speed," the US government will pay pharmaceutical giants Sanofi and GSK up to $2.1 billion for the development of a COVID-19 vaccine, the companies said.