Suspected influenza cases are rising rapidly in South Korea, raising the prospect of an earlier-than-usual flu season. The rate is highest among children aged 7 to 12, prompting the Korea Disease Control and Prevention Agency to review this week's surveillance data before deciding whether to issue a flu advisory.
The agency said on the 4th that the share of patients with influenza-like illness at clinic-level medical institutions reached 13.3 per 1,000 outpatients in the 35th week of 2026, covering Aug. 23 to 29. That was up 44.6% from 9.2 the previous week and more than double the 6.4 recorded in the same period last year.
The rate has climbed steadily over the past four weeks, from 7.0 in the 32nd week to 7.5 in the 33rd, 9.2 in the 34th and 13.3 in the 35th. By age group, those aged 7 to 12 posted the highest rate at 36.5, followed by children aged 1 to 6 at 22.6. The rate was 14.9 for those aged 19 to 49 and 14.6 for those aged 13 to 18.
The influenza virus detection rate also rose to 12.3% over the same period. The strain most commonly identified recently is A(H1N1)pdm09.
COVID-19 cases have also been increasing since the start of August. Hospitalizations at 223 hospital-level medical institutions totaled 109 in the 35th week, up 78.7% from 61 a week earlier. The virus detection rate edged up to 11.7% from 11.3%.
The agency plans to review response measures with related ministries on the 8th, preparing for the possibility that the flu season begins earlier than in previous years. It will also decide whether to issue a flu advisory based on surveillance results from this week, the start of the 2026-2027 season.
Separately, the national influenza vaccination program for older adults, pregnant women and children will begin on the 21st, with schedules staggered by group.
