President Moon Jae-in ordered the government Monday to step up its contact-tracing and testing capacities in the Seoul metropolitan area as the country battles “the biggest crisis” since the beginning of the coronavirus outbreak.

Despite a fall in the number of coronavirus tests carried out over the weekend, South Korea added 615 coronavirus cases -- 580 locally transmitted and 35 imported from overseas -- in the 24 hours ending Sunday at midnight, according to the Korea Disease Control and Prevention Agency.

Moon called for mobilizing “all available resources,” including civil servants, military personnel and police officers, to assist health authorities’ epidemiological work in the Seoul metropolitan area starting this week, according to senior presidential secretary for public communication Chung Man-ho.

His instructions come at a time when stricter social distancing measures have done little to contain the spread of the coronavirus, and the surge in infections puts an increasing strain on the country’s health system.

With a third wave of coronavirus infections in full swing across the country, health officials said the Seoul metropolitan area, home to half of the country’s population, is already in a “quasi-war” state and that coronavirus cases could top 750 this week and 900 next week.

“We are facing the biggest crisis since the onset of the coronavirus in Korea, and the current wave is neither temporary nor regional, but steady and nationwide,” Na Seong-woong, a senior official from the KDCA, said at a briefing Monday.

To improve contact-tracing capacity and alleviate the heavy workloads faced by epidemiological officials, the government is drawing up a detailed plan to mobilize military and police personnel, he said.

To expand COVID-19 testing, the government will introduce a saliva test and adopt antigen tests, which are cheaper and faster than RT-PCR tests in diagnosing the coronavirus. Given that antigen tests are not as sensitive as RT-PCR tests, they will be used in circumstances requiring urgent and extensive testing, as well as on populations that are at higher risk, he added.

The country’s daily case count surpassed 600 for the second consecutive day on Monday after 631 cases were announced Sunday, 583 cases on Saturday and 629 on Friday. The seven-day average number of coronavirus cases from Nov. 29-Dec. 5 was 487.9, up 87.8 from the previous week.

As of Monday, the transmission routes were unknown for 17.8 percent of the cases reported for the past two weeks.

The R number -- the average number of secondary infections produced by a single infected person -- was estimated at about 1.23 last week. The virus curve starts to flatten out when the R number falls below 1.

Hospital beds and other resources are quickly running out. Currently, only 45 beds out of 550 that can immediately accommodate critically ill patients, or 8.2 percent, are available nationwide. In Greater Seoul, only 13 beds are left for patients in serious condition. If the country continues to see daily increases in infections in numbers over 600, hospital beds will run out in a week or two, officials said.

The average number of patients in serious or critical condition was 101 for the past week, up 26.3 percent from a week earlier, according to the KDCA.

Starting Tuesday, the government will further tighten antivirus restrictions nationwide -- raising the level of social distancing to Level 2.5 in the Seoul metropolitan area and to Level 2 outside the region -- until Dec. 28 at midnight.

Under Level 2.5 restrictions, the second-toughest in the country’s five-tier social distancing system, gatherings of more than 50 people are banned, indoor sports facilities cannot operate and establishments such as malls, stores, internet cafes and theaters must be closed after 9 p.m. These are in addition to Level 2 restrictions such as banning indoor dining at cafes all day and at restaurants after 9 p.m.

Of Monday’s locally transmitted cases, some 68.6 percent of them were posted from Greater Seoul -- 231 in Seoul, 154 in Gyeonggi Province, which surrounds the capital, and 37 in Incheon. Outside the Seoul metropolitan area, cases were registered in all cities and provinces except in Sejong and on Jeju Island.

Of the 35 imported cases reported Monday, 10 were detected at the border, while the other 25 were identified in individuals under mandatory self-quarantine in Korea. Fourteen cases were from elsewhere in Asia, 12 were from the Americas and nine came from Europe.

Thirteen of those cases involved foreign nationals.

The number of COVID-19 patients in serious or critical condition here stood at 126.

Four more people died from the virus, bringing the death toll to 549, with the overall fatality rate at 1.44 percent. 

So far, of the 38,161 people confirmed to have contracted the new coronavirus here, 29,301 have been released from quarantine upon making full recoveries, up 173 from a day earlier. Some 8,311 people are receiving medical treatment while under quarantine.

The country carried out 14,509 tests in the past day. A total of 68,010 people were awaiting results.

By Ock Hyun-ju (laeticia.ock@heraldcorp.com)