The more people who can be tested for Covid-19, the better prepared health authorities can be to prevent the spread of the disease. Hong Kong Chief Executive Carrie Lam Cheng Yuet-ngor’s government has heeded the advice of the city’s leading coronavirus experts in deciding to extend daily testing to as many as 7,000 residents. With the source of a family cluster of three infections found last week still unidentified, the measure makes sense, as does authorities’ cautious approach to relaxing social-distancing rules. The threat of another wave is being kept at bay only through strong measures and we cannot at any time be too confident and let our guard down. Testing for the coronavirus has been limited to about 2,000 people a day, a level considered by scientists to be insufficient for community safety. Lam announced yesterday the number could be substantially raised with the help of clinics and university medical schools. Greater surveillance had previously been announced for staff at the airport and homes for the elderly and disabled. There is no better way to prevent outbreaks; it leads to quick identification of cases, prompt treatment of those infected and immediate isolation to stave off a spread. Coupled with widespread wearing of face masks, border controls and social distancing, the number of cases has been kept remarkably low; no new cases were reported by the Centre for Health Protection for a second consecutive day yesterday, taking the confirmed total since the first was recorded in January to at least 1,055, with four deaths. In keeping with a strategy of vigilance, the government has extended for two more weeks from tomorrow a limit on groups of people in public to eight. That takes it through to June 4, when a candlelight vigil is held each year in Victoria Park to mark the Tiananmen Square crackdown . Authorities have dismissed criticism of the decision, saying it is in keeping with continued community protection and not aimed at preventing the vigil from taking place. Karaoke lounges, nightclubs, bathhouses and party rooms will also have to remain closed for at least another week. But other social-gathering restrictions have been relaxed. Religious meetings will be allowed with half the usual venue capacity, although there can be no food or drink. Public beaches and swimming pools can reopen with the provision of lifeguard services. Other government recreation facilities are expected to soon follow. Rules for gyms and fitness centres have also been relaxed. Such a review is to be expected when the number of cases remains negligible. But with the coronavirus still so prevalent in the wider world, Hong Kong cannot afford to rest on its laurels; vigilance has to remain the top priority. Help us understand what you are interested in so that we can improve SCMP and provide a better experience for you. We would like to invite you to take this five-minute survey on how you engage with SCMP and the news.