South Korea recorded daily new infections of the new coronavirus in the double digits for the third straight day Tuesday, but the daily tally in Seoul and neighboring areas surpassed that in Daegu and North Gyeongsang Province, the two epicenters of the fast-spreading virus.

In an unprecedented measure against the coronavirus pandemic, South Korea decided to extend all school breaks by another two weeks to April 6. All child care centers were also ordered to stay closed until April 6.

The 84 new cases, which were detected on Monday and followed 74 new cases detected on Sunday and 76 new cases last Saturday, brought the nation's total infections to 8,320, the Korea Centers for Disease Control and Prevention (KCDC) said.

Of the 84 new cases, 32 are in Daegu and five are in North Gyeongsang, the KCDC said. The total number of confirmed cases in Daegu and North Gyeongsang, the two hardest-hit regions, stood at 6,098 and 1,169, respectively.

Seoul, Incheon and Gyeonggi Province, which surrounds Seoul and Incheon, saw their new daily infections rise by 44 to 558 on Monday.

It was the first time that a daily tally in the capital area surpassed that in Daegu and North Gyeongsang as health authorities scramble to halt cluster infections across the nation.

So far, 81 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.

Two more fatalities, including a 97-year-old woman, were reported earlier in the day, but they have not been included in an official update.

The KCDC said 58 virus patients are in critical condition. The flu-like virus causes a fever, cough, runny nose and headache for most healthy people, but the risk of severe infection is high for elderly people with underlying health problems.

In South Korea, the virus has preyed on the elderly and already sick people. The KCDC said 70.4 percent of deaths were of people in their 70s and above as of Monday. Another 19.8 percent of fatalities were of those in their 60s. No death from a virus patient younger than 29 has been reported.

About 61 percent of confirmed cases have been linked to a branch of the Shincheonji religious sect in Daegu, which has a population of 2.5 million and is the country's fourth-largest city.

The pace of daily new infections has slowed markedly since the second week of this month as health authorities completed extensive testing of 210,000 Shincheonji followers at the center of the rapid spread, but the authorities are still on high alert over new clusters of infections, including at a call center in Seoul's Guro district.

While Daegu and North Gyeongsang saw signs of stabilization in new virus cases, cases of community spread with unknown origins, mostly cluster and sporadic outbreaks, are on a gradual rise.

Seoul's confirmed cases rose by 12 to 265, with at least 82 cases linked to a call center in Guro Ward and another 18 cases linked to a Protestant church and an internet cafe in Dongdaemun Ward.

Incheon's number of cases climbed by one to 31, with 19 cases linked to the Guro call center. Gyeonggi Province, which surrounds Seoul and Incheon, saw confirmed cases climb by 31 to 262, with 45 cases linked to the church in Seongnam and another 33 cases tied to the Guro call center.

The number of virus cases in Busan was unchanged at 107, with 32 patients linked to a Christian church in the Dongnae district and another eight patients linked to Shincheonji. The 32 patients of the Oncheon church in Busan are connected 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, 104 of the total 115 patients were linked to a Zumba dance class in Cheonan, the KCDC said.

Clusters of infections account for 80.6 percent of the total confirmed cases as of Tuesday, meaning that people can contract the virus if they are in close environment.

The number of people younger than 19 who tested positive for the virus stood at 352, the KCDC said.

Five more people who are tied to a church in Seongnam, south of Seoul, tested positive for the virus Tuesday, raising the total number of infections at the River of Grace Community Church to 51, local officials said.

Starting Thursday, all people coming from abroad to South Korea will be subject to "special entrance procedures," Vice Health Minister Kim Ganglip told reporters.

Kim said the government needs "in-depth discussions" before making a decision on whether to ban all religious gatherings.

Unlike other nations, which ban travel to virus-hit nations or put all people visiting virus-hit nations under mandatory two-week quarantine, South Korea has not implemented such draconian measures, except for foreigners who traveled to China's virus outbreak epicenter of Hubei province.

Instead, South Korea has tightened its immigration procedures, requiring international travelers to get fever checks and submit papers on their health conditions. They are required to download a smartphone app that will allow them to be put under supervision if they show symptoms.

Such requirements have been applied to people who have visited mainland China, Macau, Hong Kong, Iran, Italy, France, Germany, Spain, Britain and the Netherlands.

Starting Thursday, about 13,000 international travelers per day will be subject to stricter border checks, compared with the current level of some 2,000 travelers, Kim said.

South Korea will deploy about 100 more civilian and military medical teams to stem the virus contagion at airports, Kim said.

"The growth pace of confirmed patients has recently declined, but it is a very grave situation," Kim said, citing new clusters of infections in Seoul and its neighboring areas and signs of growing imported cases.

With unknown virus sufferers who have not developed symptoms apparently causing significant numbers of infections, the government has called for people to avoid non-essential gatherings in crowded places, such as religious facilities, nursing homes, internet cafes and "noraebang," or singing rooms.

KCDC Deputy Director Kwon Jun-wook told reporters that South Korean scientists have begun research on how virus patients' immune systems respond to the coronavirus.

By analyzing blood samples from virus patients, researchers aim to understand how the virus changes as time goes by and why it develops serious respiratory problems for elderly people with underlying illnesses, Kwon said.

Two experts from the World Health Organization (WHO) are set to arrive in South Korea on Wednesday, and they will join the research, Kwon 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.

On Sunday, the government designated Daegu and three other hard-hit areas in North Gyeongsang as "special disaster zones," allowing it to subsidize about half of the recovery spending and exempt people there from taxes and utility fees.

WHO declared last week that the global coronavirus crisis is a pandemic as the virus has spread to every continent except Antarctica.

South Korea has released a total of 1,401 fully recovered novel coronavirus patients from hospitals as of Monday, up 264 from a day earlier, the KCDC said.

The number of daily cured people exceeded the number of daily new infections in South Korea last week for the first time since Jan. 20, when the virus was first detected on South Korean soil.

The number of people being checked for the virus and under quarantine came to 17,291 as of Monday, up 2,320 from the day before, the KCDC said. The country has tested a total of 286,716 suspected cases, with 261,105 testing negative.

Currently, there is no evidence that the new coronavirus is airborne. WHO said the virus is transmitted through droplets or close contact.

Meanwhile, a group of software experts volunteered to develop an English-language graphic information service on the situation of the coronavirus in South Korea.

The service is available at http://coronapath.info/eng.html and is based on the daily KCDC data. (Yonhap)