Additional COVID-19 Vaccine Booster Shots for Immunocompromised Start from the 15th... Primary Vaccination Also Switches to 'Bivalent Vaccine'

KDCA's Vaccination Plan for High-Risk Groups in the First Half of the Year
390,000 People Who Received Additional Winter Vaccinations
Those Aged 65 and Over Must Have Medical Staff Recommendation

The vaccination plan for the first half of this year targeting immunocompromised individuals and some high-risk groups aged 65 and older for COVID-19 has been announced. Despite the World Health Organization (WHO) lifting the Public Health Emergency of International Concern (PHEIC), health authorities plan to implement additional vaccinations to effectively manage daily life and prevent severe illness and death among immunocompromised individuals.

COVID-19 Vaccination. [Image source=Yonhap News]

On the 10th, the Korea Disease Control and Prevention Agency (KDCA) announced the "COVID-19 High-Risk Group Vaccination Plan for the First Half of 2023." This vaccination targets immunocompromised individuals aged 12 and older who have previously received the bivalent vaccine. Among the total 1.32 million immunocompromised individuals, 390,000 who have already received the bivalent vaccine are eligible. Additionally, those aged 65 and older who have previously received the bivalent vaccine and are recommended for vaccination based on medical judgment can also participate in this vaccination.

Vaccination is possible three months (90 days) after the last vaccination date, with a recommendation to vaccinate after six months (180 days). The preferred vaccines are BA.4/5-based bivalent vaccines (Pfizer, Moderna), but vaccination with BA.1-based bivalent vaccines is also possible. For those contraindicated for mRNA vaccines or who do not wish to receive mRNA vaccines, recombinant vaccines such as Novavax or SKYCovione (SK Bioscience) will be used as supplementary options.

Pre-registration and same-day vaccinations will begin on the 15th, with scheduled vaccinations based on pre-registration starting on the 29th. The recommended vaccination period for the first half of the year is from the 15th of this month to the 30th of next month, considering the interval with winter vaccinations. For those aged 65 and older, vaccination is possible based on clinical judgment by medical staff, so if vaccination is necessary, a recommendation from medical personnel is required.

Additionally, the KDCA announced plans for the use of bivalent vaccines for primary vaccination, considering major international trends and research results on bivalent vaccine utilization. Accordingly, bivalent vaccines will be used for those who have not completed primary vaccination (those unvaccinated for the first dose or those who have received the first dose but not the second). Since the antibody positivity rate for those aged 5 and older in Korea reaches 98.6%, it is expected that sufficient immune effect can be achieved with a single dose, so the previously two-dose regimen will be reduced to one dose.

The primary vaccination will also use the BA.4/5-based bivalent vaccine. Recent studies confirm that the BA.4/5 vaccine has higher immunogenicity against the currently circulating XBB.1 variant compared to the BA.1 vaccine. This will be applied starting from the 30th of this month.

Ji Young-mi, Commissioner of the KDCA, stated, "Our top priority is to prevent severe illness and death among high-risk groups due to COVID-19, and we are making every effort to ensure timely vaccination." She added, "We urge immunocompromised individuals to actively participate in this vaccination. Currently, 70% of immunocompromised individuals and 60% of those aged 65 and older have not received the bivalent vaccine during last winter, but vaccination is still available for those who wish to receive it, so we ask for the interest and participation of many."