South Korea's new COVID-19 cases fell below 50,000 on Sunday, but health authorities remained on edge over a possible spike in transmissions in the winter season.

The country reported 47,028 new COVID-19 infections, including 70 cases from overseas, bringing the total caseload to 26,937,516, according to data from the Korea Disease Control and Prevention Agency.

This marked the first time in six days that the daily cases have fallen below 50,000. The latest reading was down from the previous day's 52,788 but increased over 1,000 compared with a week earlier.

Daily cases tend to go down over weekends due to fewer coronavirus tests.

Health authorities are worrying that transmissions could be spiking in time for winter, bracing for the possibility of the daily infections spiking to as many as 200,000.

Concerns are growing, in particular, about senior citizens as they account for a large proportion of daily deaths from the coronavirus.

The KDCA reported 39 deaths from COVID-19, raising the total death toll to 30,369. Of the latest figure, 35 people, or nearly 90 percent, were aged 60 or older.

The number of critically ill patients came to 481, up three from the previous day, the data showed. (Yonhap)