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Meta-Analysis
. 2021 Nov 30:9:775224.
doi: 10.3389/fpubh.2021.775224. eCollection 2021.

The Disease Severity and Clinical Outcomes of the SARS-CoV-2 Variants of Concern

Lixin Lin  1 , Ying Liu  2 , Xiujuan Tang  3 , Daihai He  1
Affiliations
Meta-Analysis

The Disease Severity and Clinical Outcomes of the SARS-CoV-2 Variants of Concern

Lixin Lin et al. Front Public Health. .

Abstract

With the continuation of the pandemic, many severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants have appeared around the world. Owing to a possible risk of increasing the transmissibility of the virus, severity of the infected individuals, and the ability to escape the antibody produced by the vaccines, the four SARS-CoV-2 variants of Alpha (B.1.1.7), Beta (B.1.351), Gamma (P.1), and Delta (B.1.617.2) have attracted the most widespread attention. At present, there is a unified conclusion that these four variants have increased the transmissibility of SARS-CoV-2, but the severity of the disease caused by them has not yet been determined. Studies from June 1, 2020 to October 15, 2021 were considered, and a meta-analysis was carried out to process the data. Alpha, Beta, Gamma, and Delta variants are all more serious than the wild-type virus in terms of hospitalization, ICU admission, and mortality, and the Beta and Delta variants have a higher risk than the Alpha and Gamma variants. Notably, the random effects of Beta variant to the wild-type virus with respect to hospitalization rate, severe illness rate, and mortality rate are 2.16 (95% CI: 1.19-3.14), 2.23 (95% CI: 1.31-3.15), and 1.50 (95% CI: 1.26-1.74), respectively, and the random effects of Delta variant to the wild-type virus are 2.08 (95% CI: 1.77-2.39), 3.35 (95% CI: 2.5-4.2), and 2.33 (95% CI: 1.45-3.21), respectively. Although, the emergence of vaccines may reduce the threat posed by SARS-CoV-2 variants, these are still very important, especially the Beta and Delta variants.

Keywords: COVID-19; SARS-CoV-2; disease severity; epidemic potential; mortality; variants of concerns.

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Conflict of interest statement

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Figures

Figure 1
Figure 1
Flow diagram of the search strategy and article selection process.
Figure 2
Figure 2
Pooled hazard ratio of hospitalization, ICU admission, and mortality for patients infected with Alpha variant compared to those with wild-type virus.
Figure 3
Figure 3
Pooled hazard ratio of hospitalization, ICU admission, and mortality for patients infected with Beta variant compared to those with wild-type virus.
Figure 4
Figure 4
Pooled hazard ratio of hospitalization, ICU admission, and mortality for patients infected with Gamma variant compared to those with wild-type virus.
Figure 5
Figure 5
Pooled hazard ratio of hospitalization, ICU admission, and mortality for patients infected with Delta variant compared to those with wild-type virus.
See this image and copyright information in PMC

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