J Korean Med Sci.  2022 Dec;37(50):e347. 10.3346/jkms.2022.37.e347.

Correlation Between Third Dose of COVID-19 Vaccines and Regional Case Fatality Rates During the Omicron Wave in Korea

• Jang Y
• Kim IJ
• Moon SS
• Kim SB
• Lee J

• KMID: 2537050
• DOI: http://doi.org/10.3346/jkms.2022.37.e347

Abstract

This study seeks to find the correlation between case fatality rates (CFRs) and third-dose vaccination coverage in 244 counties (si/gun/gu) of South Korea during the omicron variant wave. Multivariate regression analyses report that the higher third-dose vaccination rates were correlated with lower regional CFRs, when controlling for age structure. If the thirddose vaccination rate of a county is higher by 10%, it would have a CFR lower by 0.05% (95% confidence interval, 0.03–0.08%). As the number of cumulative confirmed cases in South Korea was 16,353,495 as of April 20, 2022, a lower CFR by 0.03–0.08% is equivalent to 4,394–12,448 lives (8.6–24.4 per 100,000) spared. County-specific characteristics, such as age structure, intensive care unit availability, and the level of non-pharmaceutical interventions may also affect the extent of this correlation. The conclusion implicates the potential role of coronavirus disease 2019 vaccines in reducing the pressure on the regional healthcare capacity.

Keyword

Coronavirus; Vaccines; Mortality; Omicron; Korea

Figure

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  Fig. 1 The county-level case fatality rates (A) and third-dose vaccination coverage (B) for COVID-19 in South Korea.

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  Fig. 2 Correlation between CFRs (age distribution controlled) and the third-dose vaccination rates during omicron wave in South Korea.CFR = case fatality rate.

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