ArticleEuro surveillance : bulletin Europeen sur les maladies transmissibles = European communicable disease bulletin2020
The impact of repeated vaccination using 10-year vaccination history on protection against influenza in older adults: a test-negative design study across the 2010/11 to 2015/16 influenza seasons in Ontario, Canada.
Article in Euro surveillance : bulletin Europeen sur les maladies transmissibles = European communicable disease bulletin, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 21 papers, 1 of them a synthesis 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.
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Who cites it
21 citing papers in PubMed, 1 synthesis or guideline pooled it, 28 citations in OpenAlex.
- Does repeated influenza vaccination attenuate effectiveness? A systematic review and meta-analysis.The Lancet. Respiratory medicine · 2023Pooled it
- Enhanced Influenza Vaccines Extend A(H3N2) Antibody Reactivity in Older Adults but Prior Vaccination Effects Persist.Clinical infectious diseases : an official publication of the Infectious Diseases Society of America · 2025Trial
- Article
- The Dual Role of Preexisting Immunity in Influenza: Protective Recall Versus Constraint of Novel Responses.Immunological reviews · 2026Review
- Effectiveness of seasonal influenza vaccine against dominant A(H1N1)pdm09 in adults ≥ 60 years: a multicenter test-negative design in Zhejiang, China, 2024-2025.BMC geriatrics · 2026Observational
- Repeat Influenza Vaccination Effects in 2021/22 and 2022/23 in a Community-Based Cohort in Hong Kong.The Journal of infectious diseases · 2026Article
- Heat effects on influenza-like illness and heterogeneity factors across regions: based on 333 cities in China.BMC public health · 2026Article
- Influenza Vaccine Effectiveness Against Hospitalizations and Emergency Department or Urgent Care Encounters for Children, Adolescents, and Adults During the 2023-2024 Season, United States.Clinical infectious diseases : an official publication of the Infectious Diseases Society of America · 2025Article
- Estimating Standard-Dose and High-Dose Fluzone Vaccine Efficacies for Influenza A Based on Hemagglutination Inhibition Titers.The Journal of infectious diseases · 2025Article
- Article
- Antibody Avidity Maturation Following Booster Vaccination with an Intranasal Adenovirus Salnavac Vaccine.Vaccines · 2024Article
- Long Prime-Boost Interval and Heightened Anti-GD2 Antibody Response to Carbohydrate Cancer Vaccine.Vaccines · 2024Article
- Article
- The impact of pre-existing influenza antibodies and inflammatory status on the influenza vaccine responses in older adults.Influenza and other respiratory viruses · 2023Article
- Article
- Sex-specific effects of aging on humoral immune responses to repeated influenza vaccination in older adults.NPJ vaccines · 2021Article
- Influence of Prior Influenza Vaccination on Current Influenza Vaccine Effectiveness in Children Aged 1 to 5 Years.Vaccines · 2021Article
- Influenza Vaccine Effectiveness Against All-Cause Mortality Following Laboratory-Confirmed Influenza in Older Adults, 2010-2011 to 2015-2016 Seasons in Ontario, Canada.Clinical infectious diseases : an official publication of the Infectious Diseases Society of America · 2021Article
- Simple models to include influenza vaccination history when evaluating the effect of influenza vaccination.Euro surveillance : bulletin Europeen sur les maladies transmissibles = European communicable disease bulletin · 2021Article
- Article
Corrections and comments
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Authors and funding
20 authors at 11 institutions in 1 country.
Funding
Abstract
IntroductionAnnual influenza vaccination is recommended for older adults, but evidence regarding the impact of repeated vaccination has been inconclusive.AimWe investigated vaccine effectiveness (VE) against laboratory-confirmed influenza and the impact of repeated vaccination over 10 previous seasons on current season VE among older adults.MethodsWe conducted an observational test-negative study in community-dwelling adults aged > 65 years in Ontario, Canada for the 2010/11 to 2015/16 seasons by linking laboratory and health administrative data. We estimated VE using multivariable logistic regression. We assessed the impact of repeated vaccination by stratifying by previous vaccination history.ResultsWe included 58,304 testing episodes for respiratory viruses, with 11,496 (20%) testing positive for influenza and 31,004 (53%) vaccinated. Adjusted VE against laboratory-confirmed influenza for the six seasons combined was 21% (95% confidence interval (CI): 18 to 24%). Patients who were vaccinated in the current season, but had received no vaccinations in the previous 10 seasons, had higher current season VE (34%; 95%CI: 9 to 52%) than patients who had received 1-3 (26%; 95%CI: 13 to 37%), 4-6 (24%; 95%CI: 15 to 33%), 7-8 (13%; 95%CI: 2 to 22%), or 9-10 (7%; 95%CI: -4 to 16%) vaccinations (trend test p = 0.001). All estimates were higher after correcting for misclassification of current season vaccination status. For patients who were not vaccinated in the current season, residual protection rose significantly with increasing numbers of vaccinations received previously.ConclusionsAlthough VE appeared to decrease with increasing numbers of previous vaccinations, current season vaccination likely provides some protection against influenza regardless of the number of vaccinations received over the previous 10 influenza seasons.
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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.