SEOUL (REUTERS, BLOOMBERG) - South Korea reported 284 new cases of coronavirus on Wednesday (Feb 26), including a US soldier, as health authorities readied an ambitious plan to test more than 200,000 members of a church hit hardest by the country's outbreak.

The new cases pushed the total tally to 1,261, with the number expected to rise as the government widens its testing.

Of the new cases, more than 130 were from Daegu city, where a branch of the Shincheonji Church of Jesus, which has been linked to outbreaks, is located, the Korea Centres for Disease Control and Prevention (KCDC) said.

The US military reported its first case of the coronavirus on Wednesday, in a 23-year-old soldier based in Camp Carroll, about 20 km from Daegu. The camp is also near a disability centre that has had its own outbreak of the virus.

The soldier is in self-quarantine at his home outside the base, according to a statement by United States Forces Korea (USFK).

"KCDC and USFK health professionals are actively conducting contact tracing to determine whether any others may have been exposed," the statement said, noting that the soldier had also recently visited Camp Walker, a base in Daegu.

On Monday, the widow of a former US soldier tested positive for the virus after visiting several bases near Daegu, including Camp Walker.

American military bases across South Korea restricted entry and imposed health screening measures at their gates this week, leading to hours-long wait for some people trying to go to work at the bases.

The US and South Korean militaries have said they are considering scaling back joint training because of mounting concerns about the coronavirus, in one of the first signs of the epidemic's fallout on global US military activities.

A twelfth death from the virus was reported on Wednesday, according to the Joongang Ilbo newspaper.

Around 80 per cent of the country's cases - including at the disability centre - are linked to the Daegu church, and to a hospital in nearby Cheongdo County, which some church members are believed to have visited.

The church said it had agreed to provide the government with contact details for all of its members and people in trainee programmes, on the understanding the information would not be made public.

"We have obtained a list of 212,000 number of the Shincheonji believers from the church last night," vice-health minister Kim Gang-lip told a media briefing. "Local governments will check whether the believers have respiratory or fever related symptoms and visit their homes to test them."

The disease is believed to have originated in a market selling wildlife in the Chinese city of Wuhan late last year and has infected about 80,000 people and killed more than 2,700 people, the vast majority in China.

About two dozen countries and territories have levied restrictions on travellers from South Korea, while flights and tours to the nation are being cancelled.

RESPONSE IN DAEGU UNDER SCRUTINY

The lack of strong containment measures from the South Korean government in the city of Daegu, where most of the cases are emerging, is sparking questions over whether the virus will continue to spread through the country.

Unlike China, which sealed off the Hubei province of 60 million on Jan 23 to contain the virus' spread, South Korea's government has declined to take draconian containment measures.

Although the streets are quieter in Daegu, the country's fourth-largest city, shops and restaurants remain mostly open and there are no restrictions on people travelling outside the city's limits.

There is rising concern that the government's moderate approach has allowed the highly infectious pathogen to spread through the country and that new cases of infection will accelerate.

The deadly coronavirus outbreak has undercut hopes of an economic recovery, and South Korean President Moon Jae-in has hinted at an extra budget to help offset the damage and raised the country's infectious disease alert to the highest level.

Mr Moon's assurances earlier this month that South Korea would terminate the disease "before long" has been undercut by its continued spread and his government, facing elections in April, is coming under pressure to contain the epidemic.

SECT LINKS TO WUHAN

More than half of South Korea's cases are linked to an obscure religious sect called Shincheonji, which translates to "new heaven and land".

Hundreds of sect members have been infected and appeared to have spread it to patients in a hospital near Daegu after a funeral for the brother of the sect's leaders was held there earlier this month.

The sect has branches in Wuhan, the Chinese city in Hubei province where the virus originated.

Although there is no evidence that the virus was brought to South Korea by sect members returning from Wuhan, the country's Centres for Disease Control and Prevention said last week that it was examining the ties between branches of the sect in South Korea and in areas of China including Hubei province.

Mr Moon has also asked health authorities to conduct an in-depth investigation into the funeral.

"We don't think the difficulties that Daegu is going through is just a Daegu problem," he said during a visit to the city on Tuesday. "We think it is a nationwide problem."