According to the announcement made on Monday, South Korea is going to be inoculating people between the ages of 60 and 64 next month.
The initial plan for the first half of the year, released last month, was to inoculate people 65 to 74.
Now, with the expansion, a total of 8.9 million people in this age group will be getting the AstraZeneca vaccine.
Specifically, seniors aged 65 to 74 will start receiving their shots on the 27th of this month and people aged 60 to 64, on the 7th of next month.
"This plan takes into account the higher rate of fatalities and critical cases of the disease among people 60 and older. After easily achieving the inital goal of 12 million for the first half, we will adjust and execute the plan to administer more so we can reach 13 million."
Also included in the first half of this year are people who deal with young children, such as caretakers and teachers of kids in grade two and below.
Doses of Pfizer will be given to essential workers and military personnel, who together total around 640-thousand people.
All this will be achieved using the additional supplies due to reach South Korea soon despite the apparent shortage going on right now.
First, the plan is to give second doses to some 1.3 million people by the third week of May and then move to expanding first doses.
Supplies for those people, according to the announcement, have been secured.
From May 14th to the first week of June, nearly 9 million doses are due to arrive in South Korea, imported directly and from the COVAX facilty.
As for Pfizer, 5 million doses will arrive in weekly batches until June.
As of Monday midnight, a total of 3.4 million people in the country have received at least their first dose, which represents 6.6 percent of the whole population.
Slightly more than half of them got AstraZeneca while the remainder were given Pfizer.
Kim Do-yeon, Arirang News.