South Korea's daily new coronavirus cases rose by over 400 for a second consecutive day Wednesday, the highest in 19 days, as cluster infections continued to pile up across the country ahead of adjustments of social distancing rules.

The country reported 470 more COVID-19 cases, including 452 local infections, raising the total caseload to 93,733, the Korea Disease Control and Prevention Agency (KDCA) said.

The country added three more deaths from COVID-19, raising the total to 1,648.

The daily case was expected to again exceed 400 on Thursday, with health authorities and local governments saying 382 new cases were confirmed as of 6 p.m. That is 12 more than the same time the previous day. Daily tallies are counted until midnight and announced the next morning.

After briefly falling below 400 on Monday due to fewer tests carried out over the weekend, the daily caseload rebounded to 446 on Tuesday.

Daily infections had been falling gradually since posting a record high figure of 1,241 on Christmas last year.

But the curve faced a gridlock recently, with the daily tally stuck in the 300s and 400s over the past weeks despite the country's social-distancing scheme that bans private gatherings of five or more people.

The greater Seoul area is currently under the Level 2 social distancing scheme, the third highest in the country's five-tier system, while other regions are placed under Level 1.5, effective until Sunday.

Health authorities plan to decide Friday whether to extend the current curbs or not. Authorities may choose to keep the current level of distancing if there's no letup in virus cases.

Over the past week, the daily average number of new cases reached 400, nearing the threshold for the higher level of 2.5.

Under the second-highest level, the ceiling on the number of participants at events will be 50, compared to 100 under Level 2.

The warm weather is also expected to strain the virus fight down the road, as more people will carry out outdoor activities and travel.

The country is also working to finalize its new four-tier social distancing system by the end of this month. Authorities say the new policy, however, will be implemented after the virus cases fall significantly.

A total of 446,941 people, meanwhile, have been inoculated under the country's vaccination campaign that started on Feb. 26, including 60,662 the previous day.

AstraZeneca's vaccine has been given to 438,890 people, while 8,051 received that of Pfizer.

The number of people reporting adverse effects after receiving shots came to 5,786 so far, up 935 from the previous day. The majority of them were common and mild symptoms, such as headaches or fever.

The number of people who have died after receiving the jabs came to 15 so far, although their correlation has not been proven.

The country plans to allow essential public servants and businessmen to receive the jabs starting next week before going on overseas trips. They also include those traveling to participate in global sports events, such as the Olympics. 

South Korea aims to achieve herd immunity by November.

To speed up the vaccination program, authorities said they will consider providing jabs to more people than originally planned.

"We are allocating two doses for every recipient to prepare for a situation in which a new batch of vaccines does not arrive here," a local health official said.

South Korea also said it will provide AstraZeneca vaccines in an interval of up to 12 weeks, compared to the previous guideline of eight weeks.  

Of the 452 locally transmitted cases, 132 additional cases were reported in Seoul and 199 in Gyeonggi Province that surrounds the capital. Incheon, 40 kilometers west of Seoul, identified 23 new cases.

The three areas make up the greater capital region and serve as home to about half of the nation's 52 million population.

A meat market in Anseong, 77 kilometers south of Seoul, reported 20 more cases, with the total caseload reaching 97.

The number of foreign patients in Dongducheon, north of the capital city, came to 160, up six from a day earlier.

Thirteen cases were traced to a family gathering in Pyeongchang, 182 kilometers east of Seoul.

An additional case of Multisystem Inflammatory Syndrome in Children (MIS-C) has been confirmed here, bringing the total caseload to four. The symptoms of MIS-C include inflammation of the blood vessels, swollen hands and feet, vomiting, abdominal pain and diarrhea.

Over the past two weeks, cluster infections accounted for 32.3 percent of the newly added COVID-19 cases, while transmission routes for 22.5 percent remained unknown. 

There were an additional 18 imported cases, raising the total caseload to 7,225.

The number of seriously or critically ill COVID-19 patients was 123, down five from the previous day.

The total number of people released from quarantine after making full recoveries was 84,312, up 412 from a day earlier. (Yonhap)