(ATTN: ADDS details in paras 4-5, official's remarks in paras 21-22)
SEOUL, March 10 (Yonhap) -- South Korea said Tuesday it has stepped up vigilance in its battle to halt the spread of the new coronavirus, with an alarming cluster of infections emerging in Seoul, although the pace of daily new infections continued to slow.
The 131 new cases, which were detected Monday, brought the nation's total number of infections to 7,513, according to the Korea Centers for Disease Control and Prevention (KCDC).
Monday's additional cases were far below the daily increases of 500 or more last week and marked the slowest one-day rise in confirmed cases in two weeks.
So far, 54 people, mostly elderly patients with underlying illnesses, have died in South Korea from the respiratory virus that emerged in China late last year, the KCDC said. Four more fatalities were reported in Daegu earlier in the day, but they have not been included in an official update.
The KCDC said 54 virus patients are in critical conditions. The flu-like virus causes a fever, cough, runny nose or headache for most healthy people, but the risk of severe infection is high for elderly people with underlying health problems.
About 63 percent of confirmed cases have been linked to a branch of the Shincheonji religious sect in Daegu, which, at a population of 2.5 million, is the country's fourth-largest city.
The pace of daily new inflections has shown signs of slowing in recent days as health authorities have completed extensive testing of 210,000 Shincheonji followers who are at the center of the rapid spread, but authorities are still on high alert over new clusters of infections.
Of the 131 new cases, which were detected on Monday, 92 are in Daegu and 10 are in North Gyeongsang, the KCDC said. The total number of confirmed cases in Daegu and North Gyeongsang, the two epicenters of the virus outbreak here, stood at 5,663 and 1,117, respectively.
With Daegu and North Gyeongsang still accounting for some 90 percent of daily new infections, other major provinces and cities have also reported some infections.
Aside from Daegu and North Gyeongsang, cases of community spread with unknown origins, mostly cluster and sporadic outbreaks, are gradually on the rise.
Seoul's confirmed cases rose by 11 to 141, with 14 cases linked to Eunpyeong St. Mary's Hospital in Eunpyeong Ward. Another 13 cases in Seoul came from an apartment building in Seongdong Ward.
Virus cases in Busan were unchanged at 96, with 34 patients linked to a Christian church in the Dongnae district and another 11 patients linked to Shincheonji. The 34 patients of the Oncheon church in Busan are tied to the church's three-day retreat that ended on Feb. 17, officials said. It is still unclear how they were infected with the virus.
In South Chungcheong Province, which includes the city of Cheonan, 99 of the total 104 patients were tied to a Zumba dance class last month in Cheonan, the KCDC said.
Clusters of infections account for 80.2 percent of total confirmed cases.
In potential progress to find a vaccine for the global health threat, South Korean scientists have developed a "unique" protein that detects antibodies to neutralize the new coronavirus, the KCDC said.
Developing the protein makes it "possible" for researchers to find antibodies against COVID-19, it said.
In what seems to be the largest cluster of infections in Seoul so far, at least 64 people linked to a call center in southern Seoul had tested positive for the virus as of Monday, highlighting concerns about the virus' spread in confined spaces, the KCDC said.
Another 153 employees and trainees at the call center have been asked to get tested, local officials said.
The 12-story building in Shindorim-dong was shut down and disinfection work began Monday.
The infected call center workers are known to reside in Seoul, closely adjacent Incheon and neighboring Gyeonggi Province, home to more than half of the country's population of slightly over 50 million, raising concerns that the capital and neighboring areas may report additional virus cases.
KCDC Deputy Director Kwon Jun-wook told reporters that health authorities are trying to bring areas with early-stage virus clusters, including the Guro call center and the Cheonan fitness center, under control.
"Recently, the number of total confirmed cases has shown a downward trend, but health authorities are worried over such cluster infections," Kwon said.
Yoon Tae-ho, a senior health ministry official who is in charge of quarantine work, said in a daily briefing that the nation's coronavirus outbreak has entered a phase of stability but that no one should let their guard down.
The number of new confirmed cases fell over the weekend because the number of tests declined, Yoon said.
"It's a situation where we must see the trend in coming days," Yoon said.
The country is set to expand the number of isolation facilities to 12 by Tuesday, and such facilities can house as many as 3,000 virus patients, Yoon said.
Yoon urged stepped up containment efforts for confined spaces, including call centers.
Unlike China, where its ruling Communist Party put 11 million people in its virus epicenter of Wuhan under lockdown, South Korea has not imposed a restriction on internal movements.
People in Daegu have been largely calm and hailed for their voluntary efforts for self-isolation.
Yoon called recent drops in Daegu's confirmed cases "dramatic" and praised Daegu citizens for their "cooperation."
"Participation and cooperation by Daegu citizens led to a dramatic change, without extreme lockdown measures in foreign countries," Yoon said.
Since raising the virus alert level to "red," the highest level, on Feb. 23, health authorities have focused on halting the spread of the virus in Daegu and North Gyeongsang.
South Korea had released a total of 247 fully recovered novel coronavirus patients from hospitals as of Monday, up 81 from a day earlier, the KCDC said. It was the biggest one-day rise in the daily number of cured virus patients.
The number of people being checked for the virus and under quarantine came to 18,452 as of Monday, up 994 from the day before, it said. The country has tested a total of 202,631 suspected cases, with 184,179 testing negative.
Currently, there is no evidence that the new coronavirus is airborne. The World Health Organization said the virus is transmitted through droplets or close contact.