AZ Vaccine Dosing Interval Set to 11-12 Weeks... Review Underway for Additional 'Booster Shot' Procurement

Authorities: "Additional Vaccine Procurement Will Be Decided Through Discussions with Experts"

[Image source=Yonhap News]

[Asia Economy Reporter Kim Suhwan] The interval between the first and second doses of AstraZeneca (AZ) COVID-19 vaccine has been set at 11 to 12 weeks.

On the 18th, the COVID-19 Vaccination Response Promotion Team (Promotion Team) released a reference document stating, "Considering clinical trial results showing increased effectiveness with longer intervals between the first and second doses, as well as the vaccine supply situation, the second dose reservation standard date is being guided at an interval of 11 to 12 weeks."

The Promotion Team added, "Previously, during the announcement of the supplementary implementation plan for second-quarter vaccinations on the 2nd, it was stated that the AstraZeneca vaccine dosing interval would be flexibly operated within the range of 8 to 12 weeks."

This is intended to maximize the use of some of the reserved doses for the second AstraZeneca vaccination as first doses.

The reservation standard date for the second dose of the AstraZeneca vaccine has been changed twice, from the original 8 weeks to 10 weeks, and then from 10 weeks to 12 weeks.

Meanwhile, the government is reviewing the situation and plans to seek countermeasures if necessary, amid forecasts that vaccine supply instability may worsen as the United States considers a vaccine "booster shot" plan.

A booster shot refers to an additional vaccination given after a certain period to reinforce vaccine effectiveness. For vaccines like Pfizer and Moderna, which require two doses, this means administering a third dose.

The Promotion Team explained in response to related inquiries, "Regarding the additional procurement of vaccines, we plan to monitor relevant information and discuss with experts before making a decision."

The government has secured 13 million doses of the Pfizer vaccine and 20 million doses of the Moderna vaccine, based on two doses per person.