As South Korea reported a staggering total of over 600-thousand new COVID-19 cases on Thursday, authorities believe the surge is due in part to the revised testing rule, under which rapid antigen tests carried out by medical professionals are also accepted as official results.

In a Thursday briefing, senior health official Son Young-rae said that many hidden infections have come to light through the changed rule, and including Thursday's tally, the average daily caseload stands at about 387-thousand.

He said that based on forecasting models by experts and officials, the current wave is expected to peak sometime this week or early next week.

Regarding criticism that eased distancing rules have fueled the spike, Son said the country is currently in the stage of transitioning to normal life while minimizing severe cases and fatalities. He explained that seemingly conflicting government statements about stricter quarantine and a return to normality are inevitable.

As for the record number of deaths reported Thursday, Son said that according to hospital officials, about half of them are not necessarily attributable to omicron alone but to underlying diseases. He added that it is realistically impossible to differentiate the former from the latter.