ArticleVaccine2018
Seasonal influenza vaccine effectiveness against laboratory-confirmed influenza hospitalizations - Latin America, 2013.
Article in Vaccine, 2018. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 15 papers, 2 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
15 citing papers in PubMed, 2 syntheses or guidelines pooled it, 27 citations in OpenAlex.
- Does repeated influenza vaccination attenuate effectiveness? A systematic review and meta-analysis.The Lancet. Respiratory medicine · 2023Pooled it
- The Use of Test-negative Controls to Monitor Vaccine Effectiveness: A Systematic Review of Methodology.Epidemiology (Cambridge, Mass.) · 2020Pooled it
- Article
- Development and internal validation of a nomogram for predicting referral or hospitalization risk in children with community-acquired influenza.Frontiers in pediatrics · 2026Article
- Annual Estimation of Seasonal Influenza Burden in 6 South American Countries: A Retrospective Analysis of SARInet Surveillance Data to Inform Policies.The Journal of infectious diseases · 2025Article
- Expert consensus on vaccination in patients with inflammatory bowel disease in Japan.Journal of gastroenterology · 2023Article
- Severity of influenza illness by seasonal influenza vaccination status among hospitalised patients in four South American countries, 2013-19: a surveillance-based cohort study.The Lancet. Infectious diseases · 2023Article
- Factors associated with influenza vaccination coverage and willingness in the elderly with chronic diseases in Shenzhen, China.Human vaccines & immunotherapeutics · 2022Article
- Lower cognitive scores among toddlers in birth cohorts with acute respiratory illnesses, fevers, and laboratory-confirmed influenza.Influenza and other respiratory viruses · 2022Article
- Genetic evolution of influenza viruses among selected countries in Latin America, 2017-2018.PloS one · 2020Article
- Influenza vaccine effectiveness against hospitalizations in children and older adults-Data from South America, 2013-2017. A test negative design.Vaccine: X · 2019Article
- Effectiveness of Partial and Full Influenza Vaccination Among Children Aged <9 Years in Hong Kong, 2011-2019.The Journal of infectious diseases · 2019Article
- Timing of respiratory syncytial virus and influenza epidemic activity in five regions of Argentina, 2007-2016.Influenza and other respiratory viruses · 2019Article
- Article
- Influenza Vaccination in Older Adults: Recent Innovations and Practical Applications.Drugs & aging · 2019Review
Corrections and comments
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Authors and funding
9 authors at 3 institutions in 2 countries.
Funding
Abstract
backgroundDespite widespread utilization of influenza vaccines, effectiveness (VE) has not been routinely measured in Latin America.
methodsWe used a case test-negative control design to estimate trivalent inactivated influenza VE against laboratory-confirmed influenza among hospitalized children aged 6months-5years and adults aged ≥60years which are age-groups targeted for vaccination. We sought persons with severe acute respiratory infections (SARI), hospitalized at 71 sentinel hospitals in Argentina, Brazil, Chile, Colombia, Costa Rica, El Salvador, Honduras, Panama, and Paraguay during January-December 2013. Cases had an influenza virus infection confirmed by real-time reverse transcription PCR (rRT-PCR); controls had a negative rRT-PCR result for influenza viruses. We used a two-stage random effects model to estimate pooled VE per target age-group, adjusting for the month of illness onset, age and preexisting medical conditions.
resultsWe identified 2620 SARI patients across sites: 246 influenza cases and 720 influenza-negative controls aged ≤5years and 448 cases and 1206 controls aged ≥60years. The most commonly identified subtype among participants (48%) was the influenza A(H1N1)pdm09 virus followed by influenza A(H3N2) (34%) and influenza B (18%) viruses. Among children, the adjusted VE of full vaccination (one dose for previously vaccinated or two if vaccine naïve) against any influenza virus SARI was 47% (95% confidence interval [CI]: 14-71%); VE was 58% (95% CI: 16-79%) against influenza A(H1N1)pdm09, and 65% (95% CI: -9; 89%) against influenza A(H3N2) viruses associated SARI. Crude VE of full vaccination against influenza B viruses associated SARI among children was 3% (95% CI: -150; 63). Among adults aged ≥60years, adjusted VE against any influenza SARI was 48% (95% CI: 34-60%); VE was 54% (95% CI: 37-69%) against influenza A(H1N1)pdm09, 43% (95% CI: 18-61%) against influenza A(H3N2) and 34% (95% CI: -4; 58%) against B viruses associated SARI.
conclusionInfluenza vaccine provided moderate protection against severe influenza illness among fully vaccinated young children and older adults, supporting current vaccination strategies.
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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.