The number of serious COVID-19 cases is rising quickly after the nation began a transition into a system of living with the virus.

The Central Disease Control Headquarters said as of 12:00 a.m. Wednesday, a record 460 patients were in critical condition. After staying in the 300s from September 1 to last Friday, cases spiked to 411 on Saturday and have remained above 400 since.

Prime Minister Kim Boo-kyum said earlier on Wednesday that critical cases, the death toll and the virus' reproduction rate are all rising faster than expected.

While over 82 percent of the 460 critically ill are aged 60 or older, authorities believe vaccine efficacy is dropping among seniors who were one of the first groups to be immunized.

The government says it can manage the situation as less than 60 percent of hospital beds for critically ill patients are occupied as of 5 p.m. Tuesday, with 450 beds open.