SynthesisFrontiers in medicine2022
COVID-19 vaccines reduce the risk of SARS-CoV-2 reinfection and hospitalization: Meta-analysis.
Synthesis in Frontiers in medicine, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 30 papers, 3 of them syntheses that pooled it.
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
30 citing papers in PubMed, 3 syntheses or guidelines pooled it, 43 citations in OpenAlex.
- Meta-analysis of hybrid immunity to mitigate the risk of Omicron variant reinfection.Frontiers in public health · 2024Pooled it
- Pooled it
- Pooled it
- The Burden of Long-COVID-19 Among Pediatric Subjects: A Systematic Review and Meta-Analysis.Journal of clinical medicine · 2026Review
- Seroprevalence of COVID-19 neutralizing antibodies among multi-ethnic staff of an Asian primary healthcare institution: insights from point-of-care testing and implications for booster vaccination decisions.BMC infectious diseases · 2025Article
- Antiviral Activity of Medicinal Plant ExtractsPathogens (Basel, Switzerland) · 2025Article
- Article
- Dynamic monitoring of antibody titers in people living with HIV during Omicron epidemic: comparison between unvaccinated and vaccinated individuals.BMC infectious diseases · 2025Article
- Effectiveness of a single COVID-19 mRNA vaccine dose in individuals with prior SARS-CoV-2 infection: a systematic review.Communications medicine · 2025Article
- Social Disparities and Critical Illness during the Coronavirus Disease 2019 Pandemic: A Narrative Review.Critical care clinics · 2024Review
- Effectiveness of the First and Second Severe Acute Respiratory Syndrome Coronavirus 2 Vaccine Dose: A Nationwide Cohort Study From Austria on Hybrid Versus Natural Immunity.Open forum infectious diseases · 2024Article
- Impact of Spa Therapy on Symptoms and Quality of Life in Post-COVID-19 Patients with Chronic Conditions.Journal of clinical medicine · 2024Article
- Article
- The symptoms and interval of Omicron SARS-CoV-2 reinfection among healthcare workers in a hospital of Southern China: a cross-sectional study.BMC infectious diseases · 2024Article
- Comparison of Neutralizing Activity between Vaccinated and Unvaccinated Hospitalized COVID-19 Patients Infected with Delta, Omicron BA.1, or Omicron BA.2 Variant.Microorganisms · 2024Article
- Genetic determinants of SARS-CoV-2 and the clinical outcome of COVID-19 in Southern Bangladesh.Immunity, inflammation and disease · 2024Article
- Decline in academic performance and mental health during the COVID-19 pandemic: a cross-sectional survey among Sapienza University of Rome students.Frontiers in public health · 2024Article
- Investigation of epidemiological and clinical characteristics of people infected with SARS-CoV-2 during the second pandemic of COVID-19 in Chengdu, China.Frontiers in public health · 2024Article
- Self-reported side effects of COVID-19 vaccines among health professions students in India.PeerJ · 2024Article
- Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
7 authors at 3 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
The addictive protection against SARS-CoV-2 reinfection conferred by vaccination, as compared to natural immunity alone, remains to be quantified. We thus carried out a meta-analysis to summarize the existing evidence on the association between SARS-CoV-2 vaccination and the risk of reinfection and disease. We searched MedLine, Scopus and preprint repositories up to July 31, 2022, to retrieve cohort or case-control studies comparing the risk of SARS-CoV-2 reinfection or severe/critical COVID-19 among vaccinated vs. unvaccinated subjects, recovered from a primary episode. Data were combined using a generic inverse-variance approach. Eighteen studies, enrolling 18,132,192 individuals, were included. As compared to the unvaccinated, vaccinated subjects showed a significantly lower likelihood of reinfection (summary Odds Ratio-OR: 0.47; 95% CI: 0.42-0.54). Notably, the results did not change up to 12 months of follow-up, by number of vaccine doses, in studies that adjusted for potential confounders, adopting different reinfection definitions, and with different predominant strains. Once reinfected, vaccinated subjects were also significantly less likely to develop a severe disease (OR: 0.45; 95% CI: 0.38-0.54). Although further studies on the long-term persistence of protection, under the challenge of the new circulating variants, are clearly needed, the present meta-analysis provides solid evidence of a stronger protection of hybrid vs. natural immunity, which may persist during Omicron waves and up to 12 months.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.