The number of new delta variant cases accounted for 99.9 percent of new variant cases reported last week, according to the Korea Disease Control and Prevention Agency (KDCA).
The tally indicates the delta variant is the dominant strain of coronavirus in South Korea, making it more difficult for health authorities to curb the spread of the disease.
The delta variant is behind a recent spike in COVID-19 infections in Seoul and its neighboring areas while showing signs of spreading much faster into the rest of the country.
Health authorities said the country will witness more cases of the variants down the road.
The rate of variant cases detected through gene analysis came to 99.5 percent over the past week, unchanged from a week earlier, the KDCA said.
The corresponding figure for the delta variant was 99.5 percent, also unchanged from a week earlier, according to the health authorities.
On Wednesday, South Korea reported 2,028 more COVID-19 cases, raising the total caseload to 323,379. (Yonhap)