After more than two weeks of being clear of Covid-19 cases in the community, Singapore has seen a resurfacing of such cases - a sign that the virus has yet to be eradicated. It underscores the need for vigilance and to stick to safe distancing and other measures. Experts note there could be undiscovered asymptomatic cases in the community. And while most infected travellers will be detected, a small number - although they undergo quarantine and are tested - may not be picked up because of a long incubation period. The new community cases show how virulent the disease is and how easily cases can flare up. So as the economy and borders gradually open up, more community cases can be expected.

The way to prevent significant community spread is for individuals to exercise caution when going out, particularly in crowded places, taking necessary precautions such as mask-wearing, keeping a safe distance from others and ensuring proper hygiene. Importantly, they should also adhere to measures such as keeping gatherings small - by observing the current limit of five persons to a group - and being part of the track and trace scheme through the TraceTogether app or token. Taking these and other sensible steps will ensure that smaller numbers are affected should anyone be found to be infected, as well as faster tracing of close contacts. The need to minimise spread cannot be overemphasised.

Each community case that occurs comes with social and economic costs. Take the first case to arise after 16 days free of local transmissions. The patient's close contacts had to go into quarantine, including 12 relatives with whom he had dinner at a restaurant days before being diagnosed. The affected restaurant had to close for a day to be disinfected and incurred a loss of business that day. The most recent incident, in which individuals went to three mosques, led to the closure of these places of worship for at least a day, resulting in the cancellation of prayers and other activities. Any major spike or proliferation of clusters could lead to the re-imposition of lockdown measures at even greater cost.

With the start of the school holidays and as the festive season nears, Singaporeans should learn from countries and territories such as South Korea and Hong Kong, which seemed to have matters well under control only to experience significant spikes when restrictions were eased. As residents here take children for staycations or gather to celebrate with family and friends, they must exercise social responsibility and not let their guard down. The new year promises to be brighter than 2020 as vaccines herald a time when life can become more normal. But careless actions can jeopardise all that. Singaporeans would do well to act responsibly if they do not want to see out the year in very much the same way that it began.