South Korea's daily new coronavirus cases stayed above 400 for the second straight day Thursday as warm weather and the yearlong virus battle loosened citizen's vigilance against the pandemic.

The country reported 430 more COVID-19 cases, including 419 local infections, raising the total caseload to 100,276, according to the Korea Disease Control and Prevention Agency (KDCA).

The country added two more deaths from COVID-19, increasing the total to 1,709. The fatality rate was 1.70 percent, the KDCA said.

Daily infections rebounded to 428 Wednesday after falling to 346 on Tuesday. The daily caseload has stayed above 400 for six days in a row through Monday.

To curb the pandemic in the greater Seoul area, which is home to roughly half of the country's 52 million population, the KDCA extended virus curbs, the third highest in the five-tier virus restriction that were set to expire on March 14 for another two weeks until March 28.

Health authorities said they will decide Friday whether to again extend the current virus curbs by another two weeks but given the current situation, the measures are highly likely to be extended.

The greater Seoul area has been under the Level 2 social distancing measures since February. The measures include attendance caps at schools, religious activities and sports events.

Health authorities plan to step up the AstraZeneca COVID-19 vaccine rollout after confirming that there is no evidence of a correlation between the vaccines and blood clots found in some recipients.

The use of the vaccine for elderly citizens was suspended for weeks as safety concerns arose after reports of blood clots in people who received AstraZeneca products in Europe, forcing more than a dozen European countries, including Germany, France and Italy, to suspend the vaccine shots.

The country's COVID-19 vaccine rollout is expected to gather pace as AstraZeneca COVID-19 shots for elderly citizens aged 65 and older started Tuesday. Health authorities assessed there is no evidence suggesting a correlation between the vaccines and blood clots found in some recipients.

The country started administering the second Pfizer shots on Saturday.

Pfizer vaccines for some 250,000 people arrived here Wednesday for the inoculation of people aged 75 or older. The vaccines are part of Pfizer vaccines for 13 million people, which will be provided under a deal with the US pharmaceutical firm.

Under the country's vaccination program that started Feb. 26, the country seeks to vaccinate 12 million people by June. Foreigners also will be inoculated under the program.

The country aims to achieve herd immunity by November.

A total of 733,124 people had been given COVID-19 vaccine shots as of Wednesday. This accounts for around 1.4 percent of the country's population.

AstraZeneca's vaccine accounted for 673,183, while Pfizer's took up 59,941.

A total of 10,010 cases of side effects after vaccinations have been reported, but most of them have turned out to be mild symptoms, such as headaches, fever and nausea.

Sixteen deaths after vaccinations have been reported so far, the health agency said.

Of the new locally transmitted cases, 125 came from Seoul and 147 were reported from Gyeonggi Province that surrounds the capital. Incheon, 40 kilometers west of Seoul, reported 11 more cases.

The number of imported cases came to 11, down from 17 the previous day. Cases from Asian countries, except for China, stood at five, with cases from the United States and Europe at five and one, respectively.

The number of seriously or critically ill COVID-19 patients was 111, unchanged from the previous day.

The total number of people released from quarantine after making full recoveries was 92,068, up 508 from a day earlier.

South Korea has carried out 7,485,859 COVID-19 tests, including 44,649 a day earlier. (Yonhap)