South Korea's new COVID-19 cases stayed below 40,000 for the second consecutive day on Monday due largely to fewer tests being carried out over the Chuseok fall harvest holiday amid the virus slowdown.

The country reported 36,938 new COVID-19 infections, including 202 from overseas, bringing the total caseload to 24,041,825, the Korea Disease Control and Prevention Agency (KDCA).

Monday's tally is up from 28,214 counted for Sunday but marks a steady decline since last Tuesday, when the daily infection number hit over 99,000.

South Korea has seen a moderate fall in the infection numbers after they peaked at around 180,000 in mid-August as the latest virus wave is slowing down.

The country added 22 COVID-19 deaths on Monday, down from the previous day's 25, raising the death toll to 27,498, the KDCA said.

The number of critically ill patients stood at 553, up 21 from Sunday.

Health authorities have called for people to not lower their guard against the virus, as many Koreans were expected to travel to their hometowns for family gatherings during the four-day Chuseok holiday that ends Monday.

This Chuseok is the first long holiday without social distancing restrictions since the COVID-19 outbreak. (Yonhap)