With six out of the seven new community cases announced yesterday being asymptomatic, it is clear there are hidden reservoirs of Covid-19 infections in the community, experts said, as Singapore enters the third day of its reopening this morning.
The circuit breaker is a success, but the country now needs to go to the next level and beat the virus completely, and one way is to work from home whenever possible and put up with the inconveniences of not being able to have face-to-face interactions, said Associate Professor Josip Car, director of the Centre for Population Health Sciences at Nanyang Technological University's Lee Kong Chian School of Medicine.
When working from home is not possible, precautionary measures such as safe distancing and wearing masks should be followed, he added.
People also need to be reminded constantly that the outbreak is ongoing and that is a reason Singapore's reopening is taking place in phases, said Professor Teo Yik Ying, dean of the National University of Singapore's Saw Swee Hock School of Public Health.
"We have seen the example from South Korea that a single individual who went clubbing resulted in an infection chain affecting at least a hundred others," he added. "This reminds us that anyone may be infected and asymptomatic, but end up spreading the infection to many others."
Yesterday, the Health Ministry announced seven cases in the community, with an 81-year-old woman the only Singaporean among them.
She tested positive for the virus on Tuesday after she began showing symptoms on May 29. She is unlinked to other cases.
Yesterday saw 569 new coronavirus cases, bringing the total in Singapore to 36,405. Of the new cases, 562 are foreign workers living in dormitories.
There were no imported cases, and 99 per cent of the new cases are linked to known clusters.
The remaining community cases comprise three work pass holders and three work permit holders. They are five Indian national men and a Chinese national woman. Their ages range from 23 to 40. All six are linked to previously announced cases.
MOH also said that among pre-school staff, only one patient out of the 14 who tested positive for the virus was likely to be a recent infection case when they were screened. The others were likely to be cases of past infections and were no longer infectious, based on epidemiological investigations.
Two new clusters were also confirmed, both dormitories. They are at 12 Kwong Min Road and 8 Tuas South Lane.
The ministry also said the cluster at 1 North Coast Drive has been closed as no new cases had been linked to it for two incubation periods, or 28 days.
It was asked if information from digital check-in system SafeEntry - which has been used in places such as malls, supermarkets and workplaces - is being utilised to inform those who have been at locations at the same time as confirmed Covid-19 cases. The ministry replied that it does not use SafeEntry information to identify others who had gone to places visited by confirmed Covid-19 cases.
Data collected by SafeEntry is used by contact tracers when interviewing patients to help them remember where they have been and map out these places, said MOH.
"A robust activity map allows accurate and efficient identification and quarantine of close contacts to contain further transmission of the disease," it said. "We will continue to leverage technology to supplement our contact tracing efforts."
The daily average for new community cases has decreased to four in the past week from six the week before, said MOH. Across the same periods, the number of unlinked cases has remained stable at an average of two per day.
It also said 407 more patients were discharged, bringing the total number of recovered patients to 23, 573.
Currently, 334 confirmed cases are in hospital, with five in critical condition in intensive care.
Another 12,465 are isolated and cared for at community facilities, which are for those with mild symptoms or who are clinically well but still test positive for Covid-19.
Twenty-four have died from Covid-19 complications, while nine who tested positive for Covid-19 have died of other causes.
Update on cases
New cases: 569
In community: 7 (1 Singaporean; 3 work pass holders; 3 work permit holders)
In dormitories: 562
Active cases: 12,799
In hospitals: 334 (5 in ICU)
In community facilities: 12,465
Patients with Covid-19 who died from other causes: 9
Total discharged: 23,573
Discharged yesterday: 407
TOTAL CASES: 36,405