Effectiveness of the Bivalent mRNA COVID-19 Vaccine for Preventing Critical Infection From the SARS-CoV-2 Omicron Variant in the Republic of Korea
10.3346/jkms.2024.39.e258
- Author:
Young-Sook CHOI
1
;
Sukhyun RYU
;
Ryu Kyung KIM
;
Achangwa CHIARA
;
Soojin BAEK
;
Hojin NAM
;
Eunkyung PARK
;
Eun Kyoung KIM
;
Young June CHOE
;
Donghyok KWON
;
Won Suk CHOI
Author Information
1. Director for Epidemiological Investigation Analysis, Korea Disease Control and Prevention Agency, Cheongju, Korea
- Publication Type:Original Article
- From:Journal of Korean Medical Science
2024;39(37):e258-
- CountryRepublic of Korea
- Language:English
-
Abstract:
Background:This retrospective observational matched cohort study assessed the differences in critical infections caused by severe acute respiratory syndrome coronavirus 2 (SARSCoV-2) during the omicron-predominant period of the coronavirus disease 2019 (COVID-19) pandemic. We evaluated the vaccine effectiveness of bivalent mRNA vaccine compared to unvaccinated individuals.
Methods:We collected COVID-19 case data from the Korean COVID-19 vaccine effectiveness cohort. We calculated the probability of critical COVID-19 cases by comparing the vaccinated and unvaccinated groups.
Results:The risk of being critically infected due to SAR-CoV-2 infection was 5.96 times higher (95% confidence interval, 5.63–6.38) among older individuals who were unvaccinated compared to those who received the bivalent COVID-19 vaccine.
Conclusion:Our findings indicate that the bivalent vaccine reduces the disease burden of the SARS-CoV-2 omicron variant, particularly among the older population. Further studies are warranted to determine the effectiveness of booster doses of vaccines for SARS-CoV-2 infection.
