South Korea reported more than 500 new cases of COVID-19 on Wednesday as cluster infections continued to spread in various settings in and outside the greater Seoul area.

The Korea Disease Control and Prevention Agency said 522 local infections and 23 additional imported cases were confirmed in the last 24 hours, pushing the overall case count to 149,191.

One more virus-related fatality raised the death toll to 1,993.

The daily caseload has fluctuated between the 300s and 700s in recent months on the back of continued group infections from private gatherings, schools, workplaces and public facilities.

The threat of increased infections posed by more transmissible virus variants also remains a major concern health authorities are trying to get 70 percent of the country's population inoculated with coronavirus vaccines in order to reach herd immunity by fall.

So far, around 26 percent of the population have received at least one dose of a vaccine, according to the KDCA.

Nearly 7 percent, or more than 3.4 million people, have been fully vaccinated.

Officials are expected to announce on Thursday the vaccination schedule for the third quarter, which will include those aged 18 to 59.