ArticleThe Journal of infectious diseases2021
Influenza Vaccine Effectiveness Against Hospitalization in the United States, 2019-2020.
Article in The Journal of infectious diseases, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 28 papers.
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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
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Who cites it
28 citing papers in PubMed.
- Article
- Vaccination status as a determinant of hospitalization in influenza: Insights from emergency department data.European journal of clinical microbiology & infectious diseases : official publication of the European Society of Clinical Microbiology · 2026Observational
- Severity of Clinical Presentation and Outcomes in Hospitalized Adult People With Influenza by Type and Subtype, United States-2017-2020.Clinical infectious diseases : an official publication of the Infectious Diseases Society of America · 2026Article
- When to vaccinate for seasonal influenza: check the peak forecast.BMC public health · 2025Article
- Vaccine effectiveness against influenza-associated hospitalizations in adults with liver disease, 2015-2020: US Hospitalized Adult Influenza Vaccine Effectiveness Network (HAIVEN).Human vaccines & immunotherapeutics · 2025Article
- Viral Etiologies of Acute Respiratory Illness in Older Adults and of Congestive Heart Failure and Chronic Obstructive Pulmonary Disease Exacerbations Requiring Hospitalization During 2 Prepandemic Respiratory Seasons.Open forum infectious diseases · 2025Article
- Antigenic Characterization of H1N1 Influenza Viruses That Circulated During the 2019-2020 Season in Philadelphia, Pennsylvania.Influenza and other respiratory viruses · 2025Article
- Mapping climate change-driven epidemics.Frontiers in epidemiology · 2025Article
- Does the South African government have a duty to fund influenza vaccination of adults 65 years and older?Frontiers in public health · 2024Article
- Co-evolution of immunity and seasonal influenza viruses.Nature reviews. Microbiology · 2023Review
- Article
- The Impact of Adjuvanted Influenza Vaccine on Disease Severity in the US: A Stochastic Model.Vaccines · 2023Article
- Vaccine Effectiveness Against Influenza-Associated Urgent Care, Emergency Department, and Hospital Encounters During the 2021-2022 Season, VISION Network.The Journal of infectious diseases · 2023Article
- 2019-2020 H1N1 clade A5a.1 viruses have better in vitro fitness compared with the co-circulating A5a.2 clade.Scientific reports · 2023Article
- The Impact of Coronavirus Disease 2019 on Viral, Bacterial, and Fungal Respiratory Infections.Clinics in chest medicine · 2023Review
- Double Negative Control Inference in Test-Negative Design Studies of Vaccine Effectiveness.ArXiv · 2023Article
- 2019-20 H1N1 clade A5a.1 viruses have betterbioRxiv : the preprint server for biology · 2023Article
- Article
- Comparison of influenza and COVID-19 hospitalisations in British Columbia, Canada: a population-based study.BMJ open respiratory research · 2023Article
- Curcumin-Loaded Oil-Free Self-Assembled Micelles Inhibit the Influenza A Virus Activity and the Solidification of Curcumin-Loaded Micelles for Pharmaceutical Applications.Pharmaceutics · 2022Article
Corrections and comments
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Authors and funding
16 authors.
Funding
Abstract
backgroundInfluenza causes significant morbidity and mortality and stresses hospital resources during periods of increased circulation. We evaluated the effectiveness of the 2019-2020 influenza vaccine against influenza-associated hospitalization in the United States.
methodsWe included adults hospitalized with acute respiratory illness at 14 hospitals and tested for influenza viruses by reserve-transcription polymerase chain reaction. Vaccine effectiveness (VE) was estimated by comparing the odds of current-season influenza vaccination in test-positive influenza cases vs test-negative controls, adjusting for confounders. VE was stratified by age and major circulating influenza types along with A(H1N1)pdm09 genetic subgroups.
resultsA total of 3116 participants were included, including 18% (n = 553) influenza-positive cases. Median age was 63 years. Sixty-seven percent (n = 2079) received vaccination. Overall adjusted VE against influenza viruses was 41% (95% confidence interval [CI], 27%-52%). VE against A(H1N1)pdm09 viruses was 40% (95% CI, 24%-53%) and 33% against B viruses (95% CI, 0-56%). Of the 2 major A(H1N1)pdm09 subgroups (representing 90% of sequenced H1N1 viruses), VE against one group (5A + 187A,189E) was 59% (95% CI, 34%-75%) whereas no VE was observed against the other group (5A + 156K) (-1% [95% CI, -61% to 37%]).
conclusionsIn a primarily older population, influenza vaccination was associated with a 41% reduction in risk of hospitalized influenza illness.
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