The Covid-19 pandemic shows no signs of flagging, with cases worldwide breaching the nine million mark and infection numbers hitting a new daily high.

In a clear sign that the coronavirus continues to rage across the globe, flare-ups occurred in the United States and new cases hit Germany and Australia, while countries such as Brazil and India continued to see the number of cases soar.

In Singapore, experts are concerned over crowds forming at malls and eateries, as people marked their first weekend of relative freedom from widespread restrictions with exuberance.

Said Professor Teo Yik Ying, dean of the National University of Singapore's (NUS) Saw Swee Hock School of Public Health: "I am deeply concerned by the crowds that I see on the news and in social media.

"The public is behaving as if the outbreak no longer exists."

The global case count has now crossed nine million, according to data site Worldometer.

Meanwhile, the World Health Organisation (WHO) said yesterday that the pandemic is still accelerating, and its effects will be felt for decades.

The WHO reported a high in cases worldwide on Sunday, with the total rising by more than 183,000 in a 24-hour period, fuelled by high numbers in North and South America which accounted for over 116,000 cases.

Brazil, the world's No. 2 coronavirus hot spot after the US, officially exceeded 50,000 coronavirus deaths on Sunday, a blow for a country already grappling with more than one million cases.

The WHO had warned last week of a new and dangerous phase of the pandemic, with people tiring of lockdowns despite the rapid spread of the disease.

Countries that have eased lockdowns have seen new clusters emerging - such as at a wholesale market in Beijing and nightspots in South Korea - and had to quickly reimpose strict measures to prevent a resurgence of infections.

In Australia, concerns were sparked by community transmission in Victoria, and the state has tightened controls amid fears of a second wave.

The numbers are believed to be driven by families having big get-togethers and not following distancing advice, according to reports.

Experts have warned that the same could happen in Singapore, which entered phase two of its reopening last Friday, with snaking queues forming outside many malls and shops.

Stable infection rates in the community and declining case numbers in migrant worker dormitories had made phase two possible.

Yesterday, there were an additional 218 cases confirmed here, with only one case in the community.

But with hidden reservoirs of the virus still lurking, the worry is that the crowds and mingling could lead to a resurgence in cases.

People must not be lulled into a false sense of security, experts warned.

Said Professor Dale Fisher, who chairs infection control at the National University Hospital: "New clusters will appear very quickly with the lack of distancing I noticed.

"Exuberance is natural, but the community needs to not crowd."

National Development Minister Lawrence Wong, co-chair of the multi-ministry Covid-19 task force, told The Straits Times that while the majority of Singaporeans are cooperating with the measures to resume activities safely, there are a few who have acted irresponsibly, and action has been taken against them.

"All of us must do our part and adjust our lifestyles and norms," he said. "This is the way to ensure a safe and sustainable reopening in phase two."