South Korea's daily new virus cases stayed in the 500s for the second straight day Tuesday due to less testing as the country accelerates a vaccine rollout amid woes over another wave of the pandemic.

The country reported 512 more COVID-19 cases, including 477 local infections, raising the total caseload to 119,898, the Korea Disease Control and Prevention Agency (KDCA) said.

Tuesday's figure was slightly up from 500 the previous day. The daily caseload usually spikes from Wednesday as more people get tested.

The average number of daily infections in the past week neared 700 as cluster infections and untraceable cases continued to grow amid increased social activities due to warmer weather.

Untraceable cases accounted for 30.3 percent of the cases confirmed last week, the highest-ever since the outbreak of the virus in late January last year.

There were three additional deaths from the virus, raising the total to 1,820. The fatality rate was 1.52 percent.

The country has designated this week as a special period to stop the rising trend of infections.

Dining-in by civil servants will be banned, and work from home as well as working half time or part of business hours will be expanded in the public sector, according to the authorities.

The greater Seoul area, where more than half of the country's 52 million people reside, is under Level 2 social distancing, the third highest in the five-tier scheme, with the rest of the country under Level 1.5.

The current social distancing level will be effective until May 2, while private gatherings of five or more people are banned nationwide.

So far, 2,409,975 people, or 4.7 percent of the population, have received one dose of the COVID-19 vaccine, up 141,937 from a day earlier, with 126,503 people, or 0.2 percent of the population, vaccinated with two doses, up 21,598 from a day ago.

AstraZeneca's vaccine took up 1,370,841 of the shots, while Pfizer's accounted for 1,039,134 according to the KDCA.

A total of 14,155 cases of side effects after vaccinations have been reported, up 546 from a day earlier, although 13,901, or 98.2 percent of the cases, were mild symptoms, such as muscle pain and fever.

A total of 62 deaths after vaccinations have been reported, up two from the previous day. Health authorities have yet to link the deaths with the vaccinations.

South Korea is striving to boost its inoculation campaign, which started in late February, amid concerns of global vaccine shortages.

From Monday, the country began inoculating pharmacists, therapists and dialysis patients, as well as 177,000 social service workers, including police officers and firefighters.

Some 126,000 soldiers over age 30 will also receive jabs from Wednesday, and vaccinations will be focused on the elderly in the first half of the year.

The country plans to open an additional 53 injection centers by Thursday, with a total of 257 vaccination centers across the nation being available.

Health authorities aim to vaccinate 3 million people by the end of this month and 12 million by the end of June. The country targets inoculating around 70 percent of the country's population with the first dose of the vaccine by September and achieving herd immunity by November.

The country has so far secured vaccines for 99 million people from the World Health Organization's global vaccine COVAX Facility project and pharmaceutical companies -- Pfizer, AstraZeneca, Moderna, Novavax and Johnson & Johnson's Janssen.

The KDCA said 250,000 doses of the Pfizer vaccine will arrive in the country Wednesday as scheduled.

KDCA chief Jeong Eun-kyeong said that if the country's vaccine supply increases in the second half of the year, the authorities could look into the possibility of people receiving COVID-19 vaccines of their choice.

She also said that health authorities are reviewing changing virus measures for those who have completed inoculations.

Of the newly confirmed locally transmitted cases, 116 came from Seoul, 191 from Gyeonggi Province and 14 from Incheon, 40 kilometers west of the capital.

The southeastern port city of Busan, the country's second-largest city, reported 30 more cases.

Among virus clusters, a nursing home in Bucheon, west of Seoul, added five more cases, raising its total to 64, while the number of cases traced to a restaurant in Sacheon, South Gyeongsang Province, rose by two to 62.

There were 35 additional imported cases, up four from the previous day, raising the total to 8,251.

Of the newly added imported cases, India and China accounted for eight cases each.

The KDCA said an additional 86 COVID-19 variant cases from Britain, South Africa and Brazil were confirmed last week, raising the total number of the three major types of variants to 535.

To better contain the Indian variant of COVID-19, the country banned non-scheduled flights coming from India to South Korea from Saturday, although flights carrying South Korean nationals are permitted on a limited basis.

The KDCA data showed the number of seriously or critically ill COVID-19 patients was 156, up 24 from the previous day.

The total number of people released from quarantine after making full recoveries was 109,695, up 845 from a day earlier, with 8,383 people being isolated for COVID-19 treatment, down 336 from a day ago.

South Korea has carried out 8,721,609 COVID-19 tests, including 48,631 the previous day. (Yonhap)