ArticleFrontiers in public health2025
Influenza vaccine effectiveness among adults aged ≥60 years in northeastern Zhejiang Province, China, 2021-2024.
Article in Frontiers in public health, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
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
0 citing papers in PubMed.
No citing paper in PubMed yet.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
14 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Background: Influenza poses a particularly severe threat to older adults, yet vaccination coverage among this vulnerable population remains suboptimal in China. To address this public health challenge, Zhejiang Province initiated a free influenza vaccination program for older residents starting in 2020. This study evaluated the effectiveness of influenza vaccination in reducing outpatient visits among adults aged ≥60 years during three consecutive influenza seasons (2021-2024). Methods: We employed a test-negative design (TND) among adults aged ≥60 years presenting with influenza-like illness (ILI) at sentinel surveillance hospitals in two cities in Zhejiang Province from October 2021 to April 2024. Standardized questionnaires were administered to collect demographic and clinical data. Respiratory specimens were tested for influenza virus types and subtypes using RT-PCR. Multivariable logistic regression models were employed to assess factors associated with vaccination status and influenza virus detection, with subsequent estimation of influenza vaccine effectiveness (VE). Results: A total of 3,796 ILI cases were enrolled, with 644 testing positive for influenza, yielding a positivity rate of 16.97%. The results of multivariable logistic regression analysis showed that age, whether vaccinated in the current year, and whether vaccinated in the previous year were the influencing factors for influenza-positive ILI cases ( Conclusion: Influenza vaccination provides moderate protection for adults aged ≥60 years, with effectiveness varying by subtype, age, and season, particularly limited in the older population aged ≥80 years.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
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.