Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Meta-Analysis
. 2022 Aug 26:10:873596.
doi: 10.3389/fpubh.2022.873596. eCollection 2022.

The effectiveness of COVID-19 vaccines in reducing the incidence, hospitalization, and mortality from COVID-19: A systematic review and meta-analysis

Kazem Rahmani  1 , Rasoul Shavaleh  1 , Mahtab Forouhi  2 , Hamideh Feiz Disfani  3 , Mostafa Kamandi  4 , Rozita Khatamian Oskooi  5 , Molood Foogerdi  5 , Moslem Soltani  6 , Maryam Rahchamani  7 , Mohammad Mohaddespour  3 , Mostafa Dianatinasab  8
Affiliations
Meta-Analysis

The effectiveness of COVID-19 vaccines in reducing the incidence, hospitalization, and mortality from COVID-19: A systematic review and meta-analysis

Kazem Rahmani et al. Front Public Health. .

Abstract

Background: Vaccination, one of the most important and effective ways of preventing infectious diseases, has recently been used to control the COVID-19 pandemic. The present meta-analysis study aimed to evaluate the effectiveness of COVID-19 vaccines in reducing the incidence, hospitalization, and mortality from COVID-19.

Methods: A systematic search was performed independently in Scopus, PubMed via Medline, ProQuest, and Google Scholar electronic databases as well as preprint servers using the keywords under study. We used random-effect models and the heterogeneity of the studies was assessed using I 2 and χ2 statistics. In addition, the Pooled Vaccine Effectiveness (PVE) obtained from the studies was calculated by converting based on the type of outcome.

Results: A total of 54 studies were included in this meta-analysis. The PVE against SARS-COV 2 infection were 71% [odds ratio (OR) = 0.29, 95% confidence intervals (CI): 0.23-0.36] in the first dose and 87% (OR = 0.13, 95% CI: 0.08-0.21) in the second dose. The PVE for preventing hospitalization due to COVID-19 infection was 73% (OR = 0.27, 95% CI: 0.18-0.41) in the first dose and 89% (OR = 0.11, 95% CI: 0.07-0.17) in the second dose. With regard to the type of vaccine, mRNA-1273 and combined studies in the first dose and ChAdOx1 and mRNA-1273 in the second dose had the highest effectiveness in preventing infection. Regarding the COVID-19-related mortality, PVE was 68% (HR = 0.32, 95% CI: 0.23-0.45) in the first dose and 92% (HR = 0.08, 95% CI: 0.02-0.29) in the second dose.

Conclusion: The results of this meta-analysis indicated that vaccination against COVID-19 with BNT162b2 mRNA, mRNA-1273, and ChAdOx1, and also their combination, was associated with a favorable effectiveness against SARS-CoV2 incidence rate, hospitalization, and mortality rate in the first and second doses in different populations. We suggest that to prevent the severe form of the disease in the future, and, in particular, in the coming epidemic picks, vaccination could be the best strategy to prevent the severe form of the disease.

Systematic review registration: PROSPERO International Prospective Register of Systematic Reviews: http://www.crd.york.ac.uk/PROSPERO/, identifier [CRD42021289937].

Keywords: COVID-19; SARS-CoV2 infection; effectiveness; hospitalization; mortality; vaccination.

PubMed Disclaimer

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
PRISMA flow diagram of the studies included in the meta-analysis.
Figure 2
Figure 2
Effectiveness of vaccines against SARS-CoV-2 infection using odds ratio in partial vaccinated individuals.
Figure 3
Figure 3
Effectiveness of vaccines against SARS-CoV-2 infection using incidence rate ratio (IRR) in partial vaccinated individuals.
Figure 4
Figure 4
Effectiveness of vaccines against SARS-CoV-2 infection using hazard ratio in partial vaccinated individuals.
Figure 5
Figure 5
Effectiveness of vaccines against COVID-19-related hospitalization in partial vaccinated individuals.
Figure 6
Figure 6
Effectiveness of vaccines against COVID-19-related mortality using hazard ratio in partial vaccinated individuals.
Figure 7
Figure 7
Effectiveness of vaccines against COVID-19-related mortality using incidence rate ratio in partial vaccinated individuals.
Figure 8
Figure 8
Effectiveness of vaccines against SARS-CoV-2 infection using odds ratio in Full vaccinated individuals.
Figure 9
Figure 9
Effectiveness of vaccines against SARS-CoV-2 infection using incidence rate ratio in full vaccinated individuals.
Figure 10
Figure 10
Effectiveness of vaccines against SARS-CoV-2 infection using hazard ratio in full vaccinated individuals.
Figure 11
Figure 11
Effectiveness of vaccines against COVID-19-related hospitalization in full vaccinated individuals.
Figure 12
Figure 12
Effectiveness of vaccines against COVID-19-related mortality using hazard ratio in full vaccinated individuals.
Figure 13
Figure 13
Effectiveness of vaccines against COVID-19-related mortality using incidence rate ratio in full vaccinated individuals.
See this image and copyright information in PMC

References

    1. Morens DM, Folkers GK, Fauci AS. The challenge of emerging and re-emerging infectious diseases. Nature. (2004) 430:242–9. 10.1038/nature02759 - DOI - PMC - PubMed
    1. Lei S, Jiang F, Su W, Chen C, Chen J, Mei W, et al. . Clinical characteristics and outcomes of patients undergoing surgeries during the incubation period of COVID-19 infection. EClinicalMedicine. (2020) 21:100331. 10.1016/j.eclinm.2020.100331 - DOI - PMC - PubMed
    1. Huang C, Wang Y, Li X, Ren L, Zhao J, Hu Y, et al. . Clinical features of patients infected with 2019 novel coronavirus in Wuhan, China. Lancet. (2020) 395:497–506. 10.1016/S0140-6736(20)30183-5 - DOI - PMC - PubMed
    1. Chen N, Zhou M, Dong X, Qu J, Gong F, Han Y, et al. . Epidemiological and clinical characteristics of 99 cases of 2019 novel coronavirus pneumonia in Wuhan, China: a descriptive study. Lancet. (2020) 395:507–13. 10.1016/S0140-6736(20)30211-7 - DOI - PMC - PubMed
    1. Organization WH . WHO Coronavirus Disease (COVID-19) Dashboard. Geneva: World Health Organization; (2020).