ArticleVaccines2020
Association between Exposure to Influenza Vaccination and COVID-19 Diagnosis and Outcomes.
Article in Vaccines, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 48 papers, 4 of them syntheses that pooled it.
What it found
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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.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
48 citing papers in PubMed, 4 syntheses or guidelines pooled it, 72 citations in OpenAlex.
- Vaccination against influenza viruses reduces infection, not hospitalization or death, from respiratory COVID-19: A systematic review and meta-analysis.Journal of medical virology · 2024Pooled it
- Association between influenza vaccination and SARS-CoV-2 infection and its outcomes: systematic review and meta-analysis.Chinese medical journal · 2022Pooled it
- The effect of influenza vaccine in reducing the severity of clinical outcomes in patients with COVID-19: a systematic review and meta-analysis.Scientific reports · 2022Pooled it
- The Association Between Previous Influenza Vaccination and COVID-19 Infection Risk and Severity: A Systematic Review and Meta-analysis.American journal of preventive medicine · 2022Pooled it
- Seasonal influenza vaccine and frequency of adverse events in health workers receiving two doses of AstraZeneca vaccine: a retrospective cohort study.Virus research · 2026Article
- Investigating the relationship between influenza vaccination and COVID-19 infection: a cohort study in Tehran.BMC infectious diseases · 2025Article
- COVID-19 in Relation to Chronic Antihistamine Prescription.Microorganisms · 2024Article
- Factors associated with outcome in a national cohort of rhinovirus hospitalized patients in Brazil in 2022.Scientific reports · 2024Article
- Association between Usage of Prophylactic AYUSH Medicines and Disease Severity in COVID-19 Patients: A Retrospective Cohort Study.Homeopathy : the journal of the Faculty of Homeopathy · 2024Article
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- Flu vaccine administration in the period before SARS-CoV-2 infection and its outcomes: An umbrella review.Preventive medicine reports · 2024Review
- Impact of COVID-19 Outbreak on Influenza and Pneumococcal Vaccination Uptake: A Multi-Center Retrospective Study.Vaccines · 2023Article
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- Patterns of utilisation of specialist care after SARS-Cov-2 infection: a retrospective cohort study.BMJ open · 2023Article
- Effectiveness of influenza vaccination against SARS-CoV-2 infection among healthcare workers in Qatar.Journal of infection and public health · 2023Article
- Influenza and Pneumococcal Vaccination and the Risk of COVID-19: A Systematic Review and Meta-Analysis.Diagnostics (Basel, Switzerland) · 2022Review
- Influenza and pneumococcal vaccination and COVID-19 in kidney transplant patients.Transplant immunology · 2022Article
- Impact of influenza vaccination on GP-diagnosed COVID-19 and all-cause mortality: a Dutch cohort study.BMJ open · 2022Article
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 1 institution in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
We explored whether influenza vaccination (IV) affects susceptibility to SARS-CoV-2 infection and clinical outcomes in COVID-19 patients in 17,608 residents of the Italian province of Reggio Emilia undergoing a SARS-CoV-2 test. Exposure to IV was ascertained and the strength of the association with SARS-CoV-2 positivity expressed with odds ratios (OR). Rates of hospitalisations and death in those found positive were assessed and hazard ratios (HR) were estimated. The prevalence of IV was 34.3% in the 4885 SARS-CoV-2 positive and 29.5% in the 12,723 negative subjects, but the adjusted OR indicated that vaccinated individuals had a lower probability of testing positive (OR = 0.89; 95% CI 0.80-0.99). Among the 4885 positive individuals, 1676 had received IV. After adjusting for confounding factors, there was no association between IV and hospitalisation (1.00; 95% CI 0.84-1.29) or death (HR = 1.14; 95% CI 0.95-1.37). However, for patients age ≥65 vaccinated close to the SARS-CoV-2 outbreak, HRs were 0.66 (95% CI: 0.44-0.98) and 0.70 (95% CI 0.50-1.00), for hospitalisation and death, respectively. In this study, IV was associated with a lower probability of COVID-19 diagnosis. In COVID-19 patients, overall, IV did not affect outcomes, although a protective effect was observed for the elderly receiving IV almost in parallel with the SARS-CoV-2 outbreak. These findings provide reassurance in planning IV campaigns and underscore the need for exploring further their impact on COVID-19.
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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.