The Republic of Korea (RoK) on Sunday surpassed one million cumulative COVID-19 cases since the pandemic began, as health officials reported a daily record of 38,691 new infections driven by an Omicron variant outbreak.

The RoK saw its first confirmed COVID-19 case on January 20, 2020, and soon became the first country outside China to battle a major outbreak.

An aggressive strategy of tracking, tracing, masking and quarantining helped the RoK to blunt that initial wave and keep overall cases and deaths low without widespread lockdowns, but the spread of the Omicron variant is driving case numbers to new highs.

Deaths have remained low in the highly vaccinated country, however, with 15 new deaths reported as of midnight Saturday, according to the Korea Disease Control and Prevention Agency.

Daily cases are nearly five times higher than two weeks ago, when the Omicron variant began to dominate, but serious infections have remained at manageable levels so far, authorities have said.

Officials on Friday announced they would extend social distancing measures for at least another two weeks, including a 9 p.m. curfew on businesses and a six-person limit for private gatherings.

Overall, the Republic of Korea has reported 1,009,688 COVID-19 cases, with 6,873 deaths.

Nearly 86% of the country's 52 million population is fully vaccinated, with more than 54.5% having received booster shots.