Relative Effectiveness of COVID-19 Vaccination in Healthcare Workers: 3-Dose Versus 2-Dose Vaccination.
J Korean Med Sci
; 37(35): e267, 2022 Sep 05.
Article
in En
| MEDLINE
| ID: mdl-36065651
ABSTRACT
The omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is known to have high infectivity and is more likely to evade vaccine immunity. However, booster vaccination is expected to strengthen cross-reactive immunity, thereby increasing the vaccine effectiveness (VE). This study aimed to evaluate the relative VE of the 3-dose (booster) vaccination compared with the 2-dose primary series vaccination in healthcare workers during omicron variant-dominant periods. During the omicron-dominant period from February 1, 2022 to February 28, 2022, a 11 matched case-control study was conducted. Healthcare workers with positive SARS-CoV-2 test results were classified as positive cases, whereas those with negative results served as controls. Compared with the 2-dose primary series vaccination, booster vaccination with mRNA vaccine showed moderate VE (53.1%). However, in multivariate analysis including the time elapsed after vaccination, the significant VE disappeared, reflecting the impact of recent vaccination rather than the third dose itself.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
COVID-19 Vaccines
/
COVID-19
Type of study:
Evaluation_studies
/
Observational_studies
Limits:
Humans
Language:
En
Journal:
J Korean Med Sci
Journal subject:
MEDICINA
Year:
2022
Document type:
Article