Comparing the effectiveness of bivalent and monovalent COVID-19 vaccines against COVID-19 infection during the winter season of 2022-2023: A real-world retrospective observational matched cohort study in the Republic of Korea

Autor: Chungman Chae, Ryu Kyung Kim, Eun Jung Jang, Ji Ae Shim, Eunkyung Park, Kil Hun Lee, Sye Lim Hong, Asma Binte Aziz, Birkneh Tilahun Tadesse, Florian Marks, Sangwoo Tak, Sangwon Lee, Donghyok Kwon
Jazyk: angličtina
Rok vydání: 2023
Předmět:
Zdroj: International Journal of Infectious Diseases, Vol 135, Iss , Pp 95-100 (2023)
Druh dokumentu: article
ISSN: 1201-9712
DOI: 10.1016/j.ijid.2023.08.010
Popis: Objectives: To compare the effectiveness of bivalent and monovalent COVID-19 vaccines throughout the 2022-2023 winter season based on real-world data. Methods: This retrospective observational matched cohort study used the national vaccination program and a surveillance dataset from the Republic of Korea, and included adults aged >18 years who received bivalent or monovalent COVID-19 vaccines between October 11, 2022, and December 17, 2022. Cox proportional hazard models were used to estimate the hazard ratio for COVID-19 infection between the groups. Results: We included 29,245 matched individuals in the bivalent and monovalent vaccine groups, respectively. The bivalent vaccine recipients showed 12.2% (95% confidence interval [CI] 6.5-17.7%) additional protection against COVID-19 infection compared with the monovalent vaccine recipients. The additional protection provided by bivalent vaccines was significantly higher among residents of long-term care facilities (39.4%, 95% CI 21.6-53.1%). Maximum additional protection was observed 3 to 4 months after completing the vaccination (17.6%, 95% CI 6.6-27.3%). Conclusion: Bivalent COVID-19 vaccines showed significantly better protection against infection than monovalent vaccines among adults during the 2022-2023 winter season. Our results highlight that immunization programs with bivalent vaccines comprising recent variants can be an effective measure to prepare for seasonal COVID-19 circulation.
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