Starting today, those over the age of 65 will be able to get flu shots free of charge.
The KDCA on Thursday said that influenza vaccination is now available for people aged between 65 and 69.
From last week, the agency offered free shots to those aged 70 and older, while children and pregnant women have been eligible since the beginning of the month.
The nation-wide influenza vaccination program covers babies from 6 months to children under the age of 13, pregnant women and those over the age of 65.
Free shots for children and pregnant women will be available until April 30 next year, while the same for seniors will be available until the end of this year.
Those who aren't eligible under the program can still receive their shots for a nominal fee at medical facilities.
Health authorities have urged the public to actively take part in flu vaccinations amid mounting concerns over a potential "twindemic" in which the flu and COVID-19 can spread at the same time. They added that, while people can receive both shots simultaneously, they should be administered on different parts of the body.