Health authorities have called for the suspension of religious gatherings and large events as part of social-distancing efforts aimed at halting the spread of the virus, a plea ignored by some churches that have continued to hold services as normal.

The KCDC on Wednesday also urged citizens to cancel all non-essential travel overseas as the number of imported cases continued to rise.

The new clusters follow the confirmation of more than 100 new cases last week at a call centre in Seoul, adding to fears the virus could rapidly spread in the metropolitan area that is home to more than 25 million people – about half the country’s population.

The KCDC confirmed 93 new cases nationwide on Wednesday – bringing the official total to 8,413, including 84 deaths – in the fourth straight day that new infections remained in the double digits.

South Korea’s coronavirus response is the opposite of China and Italy – and it’s working

Local authorities separately confirmed more than 70 new infections at a nursing home in Daegu, the southeastern city at the centre of the country’s outbreak along with surrounding Gyeongsangbuk Province. At least some of those cases were not included in the latest nationwide toll, which refers to the total calculated the previous day.

Its fatality rate from the illness stood at around 1 per cent on Wednesday, up from recent weeks but well below the global average of 3.4 per cent calculated by the World Health Organisation – a difference widely attributed to the country’s large-scale testing.

“In one sense, we should expect that clusters of cases will inevitably pop up in large countries as the pandemic progresses, particularly where social distancing interventions have not been extreme, [such] as in the strategy employed by South Korea,” said Hsu Li Yang, an associate professor at Saw Swee Hock School of Public Health at the National University of Singapore, pointing out that South Korea has a population seven and nine times larger than Hong Kong and Singapore, respectively.

“[However], having seen their success in Daegu and elsewhere, including Gyeongbuk, I think we should expect the South Koreans to get on top of each of these newer clusters as they arise.”

But some local experts have expressed concern that the slowdown in new cases may be due to authorities finishing up testing of some 200,000 members of the controversial religious sect Shincheonji – which has been linked to about 60 per cent of cases in the country – rather than an indication the situation is being brought under control.

Joong Sik-eom, a professor of infectious diseases at Gachon University in Seongnam, warned in an interview with local media last week that the country appeared to be in the early stages of a localised pandemic.

Coronavirus: South Korea declares hard-hit areas ‘disaster zones’

“If you exclude Shincheonji, the situation looks similar to other countries,” Joong told Hankyoreh 21. “If you look at the emergence of regional clusters of 1,500-2,000 people and the number of cases, we are heading toward a situation like that of France. If you take out Shincheonji and look at the remaining data, it has been steadily rising from the first patient.”

Ben Cowling, an infectious diseases expert at the University of Hong Kong, said although the rise in cases in South Korea remained low, “there will always be a risk of a surge in cases resulting from silent transmission – infection spread by cases that have not been detected in the community”.

“We have the same concern in Hong Kong,” Cowling said.