The quarantine authorities predicted Monday that the Omicron variant might also emerge as the dominant strain in Korea in one or two months.

"There is a possibility that Omicron variant may become the dominant Covid-19 virus in a month or two here," said Lee Sang-won, director of epidemiological investigation and analysis at the Central Disease Control Headquarters. "If we prevent the infection more staunchly, it might come a little later."

Officials noted that the Omicron variant's propagation rate is very high.

Since the end of November, health officials have confirmed 178 Omicron cases in Korea, and 10 suspected cases, making the total related to the Omicron variant at 188.

Of the 188 cases, 19.8 percent of patients were asymptomatic, and those with symptoms showed mild illnesses fever, sore throat, and cough. However, the family infection rate of confirmed patients was 44.7 percent, more than double the Delta variant’s 20 percent.

Authorities also noted that they have confirmed five Omicron infections from even fully vaccinated people.

Three out of five patients had received a booster vaccination after completing the primary vaccination with the Janssen vaccine. Of the remaining two, one completed the primary vaccination with AstraZeneca's vaccine and then received a booster dose with Pfizer's vaccine, and another received three Pfizer shots.

The government has vaccinated 43,493,325 people – 11,134,803 with the AstraZeneca vaccine, 24,085,077 with Pfizer's vaccine, 1,506,561 with Janssen's vaccine, 6,758,429 with Moderna's vaccine – with the first shot of the vaccine up 5,851 from the previous day. In addition, it has provided more than 11.5 million booster shots to older adults and other vulnerable groups.

As of Tuesday, 81.9 percent of Koreans were fully vaccinated, 84.7 percent had received their first shots, and 22.5 percent had received booster shots.

President Moon Jae-in instructed national university hospitals to focus their medical resources on treating critically ill Covid-19 patients as the country has seen a surge in serious cases.

The nation confirmed an all-time high of 1,025 critically ill patients on Sunday amid a shortage of hospital beds across the country.

"I want national university hospitals to focus their medical capacities on treating severely ill Covid-19 patients," Moon said during a meeting with his aides. “Securing of the sickbeds is entirely the responsibility of the government."

Moon added that the government prepared for the increase of patients by nearly doubling the number of hospital beds and expanding home treatment over the past year. Still, it was not enough to support daily recovery.

During the meeting, President Moon called for the national university hospitals to focus on treating Covid-19 patients while asking as many public hospitals as possible in the Seoul metro region to convert into facilities exclusively responsible for treating Covid-19 patients.

"Please use the public sector medical personnel as much as possible to treat corona patients," Moon said. "Except for the minimum required personnel, military surgeons and public health doctors specializing in Covid-19 treatment should be assigned to hospitals for critically ill patients."

Moon also instructed health officials to help Covid-19 hospitals with sufficient financial support and compensation for their losses and told his aides to create a government-civilian task force charged with resolving the issue of bed shortages.

On Monday, the Korea Disease Control and Prevention Agency (KDCA) confirmed 5,318 new virus cases, including 5,258 local infections, raising the cumulative caseload to 570,414.

The number of critically ill patients came to 997, slightly down from an all-time high of 1,025 on Sunday and 1,016 on Saturday.

An additional 54 people died of Covid-19, lifting the death toll to 4,776, with a fatality rate of 0.84 percent.

To stem out the spread of the virus, the government had re-imposed a set of revised virus restrictions across the country, which will remain in effect until Jan. 2, from last Saturday.

Under the new measures, the government has decreased the maximum size of private gatherings to four people nationwide, from the previous limit of six in the capital area and eight elsewhere, while applying a 9 or 10 p.m. curfew to businesses depending on their type of service.