SEOUL - The streets of Seoul quietened down on Monday (Aug 31) as South Korea entered its second day of tightened social distancing aimed at curbing a two-week spike that increased coronavirus infections to 19,947, with indoor golf simulators closed for the first time while cafe chains operated on takeout orders only.

However, questions have arisen about the effectiveness of this so-called Level 2.5, out of a three-tier system which would ban gatherings of more than 10 people at its strictest.

The current level prohibits only gatherings of 50 people indoors and 100 outdoors.

Wary of economic and social repercussions if social distancing is raised to the highest Level 3, health authorities focused efforts on discouraging social gatherings of young people aged between 20 and 40, who accounted for nearly 40 per cent of confirmed cases last week.

Cafe chains popular for hanging out, such as Starbucks and A Twosome Place, have been ordered to operate on takeout orders only.

All restaurants will also have to cease dining operations from 9pm, aimed at stopping the social practice of going for second and third round of gatherings after dinner. Takeout and delivery will still be permitted from 9pm to 5am.

Indoor sports facilities popular with this age group, including billiard and indoor golf, have also been told to close.

However, observers have questioned if this scheme is effective, pointing out that cafe lovers can easily switch to non-franchise brands, while friends can continue to gather in big numbers at home.

The ChosunBiz newspaper, for one, said there are "holes everywhere" in the government's latest policy, noting that people are now chatting over coffee at bakery cafes, fast food joints and even convenience stores with outdoor seating. Golfers, meanwhile, are gathering at outdoor driving ranges instead of indoor facilities.

Inha University's consumer science professor Lee Eun-hee said it is "nonsensical" to allow bakery cafes to operate as normal while restricting cafe chains.

"Policies made during this time should be more elaborate and detailed. There should not be any quarantine holes, and no controversy about equality within the industry," she said. "The government should also consider how to induce the behaviour of consumers who value individual freedom."

The health authorities have urged people to stay at home and refrain from joining social gatherings as much as possible during a "standstill week" to last from Aug 30 to Sept 6.

The country reported 248 new cases on Monday. The death toll stands at 324.

A major cluster linked to the Sarang Jeil Church in central Seoul accounted for 1,056 cases, out of which 21 are new. A separate 399 infections are traced to a Aug 15 rally in Seoul organised by the church, which drew some 50,000 people from all over the country.

The number of untraceable infections has also grown to worrying levels. The Korea Centres for Disease Control and Prevention (KCDC) said on Monday that the origin of 22.7 per cent of the 4,432 cases confirmed in the past two weeks remain unclear, and this is the highest figure since they started compiling data in April.

This is feared to pose a major risk to the country's efforts to curb the outbreak using aggressive contact tracing and massive testing.

The number of critically-ill patients has also more than doubled in the last week, reaching 79 on Monday, while 76 per cent of hospital beds set aside for coronavirus patients in Seoul and greater Seoul have been occupied.

Senior health official Yoon Tae-ho said the goal is to maintain the downward trend of new virus cases. The daily figure has been falling since Aug 27's 441 - the highest in this round of the outbreak. "Tightened measures can be eased only if our quarantine system is deemed to have recovered its ability to control the virus situation," he added.

Ms Kim Ye-seul, 26, a customer service specialist, told The Straits Times that she has been working from home since Aug 24 when her company shut down completely.

"I used to spend my spare time taking ballet lessons and hanging out with friends outside, but both have been cancelled. Going to cafes for desserts is not safe any more so I bought a waffle maker," she said.

Mr Alexander Kim, 46, who owns an indoor golf simulator club, said he has received seven calls from customers wanting to make a booking, unaware that the place has been ordered to close since Sunday. If not, he will be fined.

"Of course, I worry about income, but I also hope the coronavirus situation will subside soon," he said.