Health authorities have issued a flu advisory for the first time in three years.

The Korea Disease Control and Prevention Agency(KDCA) said on Friday that the influenza advisory was issued after the rate of symptomatic doctors per one-thousand people jumped to five-point-one in the week from September 4 to 10.

The advisory was issued for the first time since 2019, before the COVID-19 pandemic, coming much earlier than the typical November or December month of issuance.

This is after health authorities tightened its flu advisory standard in light of an expected “twindemic” this winter in which cases of influenza and COVID-19 spike concurrently.  

The authorities applied the rate of four-point-nine symptomatic doctors per one-thousand people to this year's flu advisory standard, down from five-point-eight last year.