Health authorities will begin administering free influenza shots to high-risk groups starting from Wednesday as the country seeks to ward off a serious outbreak.

The Korea Disease Control and Prevention Agency(KDCA) said on Monday that inoculations would be made available for children between six months and 13 years old, pregnant women and those aged 65 or older at some 20-thousand hospitals and medical facilities nationwide.

Shots will be administered from Wednesday for children who have never received a flu vaccine and must receive two doses, while children between the ages of 6 and 13 who only need one shot will be able to receive it from October 5.

Those over the age of 65 will be able to receive the flu vaccine from October 12.

KDCA chief Peck Kyong-ran encouraged the public to get their flu shots, emphasizing its importance this year as natural immunity against the flu has waned over the last two years.