Most circuit breaker measures will be lifted from tomorrow, but life should not go back to normal, warn experts, if Singapore wants to avoid a second round of circuit breaker measures.

For more than a week, the number of unlinked Covid-19 cases in the community has been in the single digits. But low numbers do not mean an all-clear and, in fact, these unlinked infections show there are hidden reservoirs in the community and transmission is still going on in the country.

Professor Teo Yik Ying, dean of the National University of Singapore's (NUS) Saw Swee Hock School of Public Health, said: "The reality is that Singapore, like China, South Korea, New Zealand and other countries, remains at risk despite the low numbers."

Dr Asok Kurup, a specialist in private practice, concurred: "If anything, the South Korean nightclub saga and Beijing market story are lessons that we, too, may see some weak links somewhere, however well we have defined safety standards."

After South Korea eased its measures early last month, more than 100 coronavirus cases emerged among nightspot patrons, possibly spread by a 29-year-old man who had club-hopped. Beijing implemented a partial lockdown this week - including cancelling flights and closing schools - following an outbreak of Covid-19 linked to a food market last week, with more than 130 people infected so far.

Prof Teo said: "We need to continue to be mindful of the risk involved, especially when there are going to be more interactions between people now."

Associate Professor Alex Cook, vice-dean of research at the NUS Saw Swee Hock School of Public Health, said: "We have few cases. We are better prepared. Yet the population is still almost entirely susceptible. So it's like we're back to February - not to before the pandemic started - and we need to act accordingly."

Since this is a new virus, no one is immune to it. There are not enough people who have recovered from Covid-19 to provide herd immunity which could reduce its spread.

Professor Dale Fisher, a senior infectious disease consultant at the National University Hospital, said: "The community needs to fear a reversal of the opening up and behave in many ways like in phase one if possible."

Prof Cook, an expert in disease modelling used to predict trends, added: "Any second wave would be starting from a low base, so even if the epidemic picked up speed, it would take some time for our healthcare capacity to be threatened."

But he warned that pandemics do not always pan out as expected. "If we reached 25 per cent of our intensive care unit capacity, I would be very worried. If an out-of-control epidemic doubles every week, then reaching such a level would mean we are two weeks from disaster."

Looking at what is happening in Britain, which had not taken the pandemic seriously at the start and now has close to 300,000 cases and 42,000 deaths, Prof Cook said that had Singapore not taken stringent measures, there would have been 3,000 to 4,000 deaths here by now - instead of 26.

Dr Kurup pointed out that Singapore is a small nation and densely populated, so how things play out will depend a lot on community behaviour.

India is also densely populated. It eased lockdown measures earlier this month and is now seeing thousands of new cases and hundreds of deaths daily.

Prof Teo said it is important for people to be sensible about their activities and not take the easing of measures to mean everything is fine now. Even though the Government has required safe management protocols to be put in place at public spaces and malls, the reality is that the best protocols and safeguards are meaningless if people do not adhere to them, he said.

"If people think that with the easing of rules in phase two, it means they can take advantage of it and start to meet multiple disparate groups of people, then such action will clearly increase the person's risk of being infected."

Even if everyone wears a mask when out and keeps a 1m distance from others, it does not guarantee he will not get infected. Masks help to cut the transmission of the virus, but do not stop it altogether.

This is why companies are encouraged to continue work-from-home practices where possible, to reduce the risk of their staff getting infected at the workplace or while commuting daily in trains or buses.

Dr Kurup advised: "People should adopt the new normal. It is not going to be life as usual pre-pandemic.

"This is not the time to have multiple dining sessions with different groups on consecutive days. Be less of a social animal and always remember that the virus is tenacious whereas humankind is fallible."

As Health Minister Gan Kim Yong said when announcing tomorrow's further easing of measures, there is only so much the Government can do. People need to cooperate with the spirit, rather than just the letter of the law.

"I'm sure that even as we draw up the rules, people will be thinking of how to get around the rules," he said. "You can fool the rules, but you cannot fool the virus. If you violate the rules, the virus will get to you."

Said Prof Fisher: "If everyone in the country follows the guidelines, then clusters will be uncommon, small and brief. This will allow us to live with the virus."

He said people should remember that Covid-19 is "highly lethal" to older people and a small number of younger people, especially if they have hypertension and diabetes, which are very common here.

He added: "Even young, healthy people can pass the virus to their parents or grandparents, so we don't want to see numbers rise. It's very serious and people can die."

Agreeing, Professor Leo Yee Sin, executive director of the National Centre for Infectious Diseases, said: "We need to protect the vulnerable groups, specifically older folks and those with weakened immunity. It is prudent to consider the impact on the vulnerable groups for every step of relaxation.

"This is best done in a more cautious manner and assessed along the way to learn the best move forward until we have a definitive solution, such as an effective, safe, affordable, accessible vaccine, or other means to achieve herd protection, or mechanisms to protect the entire population."