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
Review
. 2022 Feb 14;2(1):e22.
doi: 10.1017/ash.2021.261. eCollection 2022.

The long-term effectiveness of coronavirus disease 2019 (COVID-19) vaccines: A systematic literature review and meta-analysis

Alexandre R Marra  1   2   3 , Takaaki Kobayashi  1 , Hiroyuki Suzuki  1   3 , Mohammed Alsuhaibani  1   4 , Marin L Schweizer  1   3 , Daniel J Diekema  1 , Bruna Marques Tofaneto  5 , Luigi Makowski Bariani  5 , Mariana de Amorim Auler  5 , Jorge L Salinas  6 , Michael B Edmond  7 , João Renato Rebello Pinho  8 , Luiz Vicente Rizzo  2
Affiliations
Review

The long-term effectiveness of coronavirus disease 2019 (COVID-19) vaccines: A systematic literature review and meta-analysis

Alexandre R Marra et al. Antimicrob Steward Healthc Epidemiol. .

Abstract

Background: Although multiple studies revealed high vaccine effectiveness of coronavirus disease 2019 (COVID-19) vaccines within 3 months after the completion of vaccines, long-term vaccine effectiveness has not been well established, especially after the δ (delta) variant became prominent. We performed a systematic literature review and meta-analysis of long-term vaccine effectiveness.

Methods: We searched PubMed, CINAHL, EMBASE, Cochrane Central Register of Controlled Trials, Scopus, and Web of Science from December 2019 to November 15, 2021, for studies evaluating the long-term vaccine effectiveness against laboratory-confirmed COVID-19 or COVID-19 hospitalization among individuals who received 2 doses of Pfizer/BioNTech, Moderna, or AstraZeneca vaccines, or 1 dose of the Janssen vaccine. Long-term was defined as >5 months after the last dose. We calculated the pooled diagnostic odds ratio (DOR) with 95% confidence interval for COVID-19 between vaccinated and unvaccinated individuals. Vaccine effectiveness was estimated as 100% × (1 - DOR).

Results: In total, 16 studies including 17,939,172 individuals evaluated long-term vaccine effectiveness and were included in the meta-analysis. The pooled DOR for COVID-19 was 0.158 (95% CI: 0.157-0.160) with an estimated vaccine effectiveness of 84.2% (95% CI, 84.0- 84.3%). Estimated vaccine effectiveness against COVID-19 hospitalization was 88.7% (95% CI, 55.8%-97.1%). Vaccine effectiveness against COVID-19 during the δ variant period was 61.2% (95% CI, 59.0%-63.3%).

Conclusions: COVID-19 vaccines are effective in preventing COVID-19 and COVID-19 hospitalization across a long-term period for the circulating variants during the study period. More observational studies are needed to evaluate the vaccine effectiveness of third dose of a COVID-19 vaccine, the vaccine effectiveness of mixing COVID-19 vaccines, COVID-19 breakthrough infection, and vaccine effectiveness against newly emerging variants.

PubMed Disclaimer

Figures

Fig. 1.
Fig. 1.
Literature search for articles on the long-term COVID-19 vaccine effectiveness among general population.
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

References

    1. Polack FP, Thomas SJ, Kitchin N, et al. Safety and efficacy of the BNT162b2 mRNA COVID-19 vaccine. N Engl J Med 2020;383:2603–2615. - PMC - PubMed
    1. Dagan N, Barda N, Kepten E, et al. BNT162b2 mRNA COVID-19 vaccine in a nationwide mass vaccination setting. N Engl J Med 2021;384:1412–1423. - PMC - PubMed
    1. Tenforde MW, Olson SM, Self WH, et al. Effectiveness of Pfizer-BioNTech and moderna vaccines against COVID-19 among hospitalized adults aged ≥65 years—United States, January–March 2021. Morb Mortal Wkly Rep 2021;70:674–679. - PMC - PubMed
    1. Marra AR, Kobayashi T, Suzuki H, et al. The short-term effectiveness of coronavirus disease 2019 (COVID-19) vaccines among healthcare workers: a systematic literature review and meta-analysis. Antimicrob Steward & Healthc Epidemiol 2021;1(1):e33. - PMC - PubMed
    1. Voysey M, Clemens SAC, Madhi SA, et al. Safety and efficacy of the ChAdOx1 nCoV-19 vaccine (AZD1222) against SARS-CoV-2: an interim analysis of four randomised controlled trials in Brazil, South Africa, and the UK. Lancet 2021;397:99–111. - PMC - PubMed

LinkOut - more resources