ReviewBMC infectious diseases2018
The role of pneumonia and secondary bacterial infection in fatal and serious outcomes of pandemic influenza a(H1N1)pdm09.
Review in BMC infectious diseases, 2018. The graph could read no effect estimate from its abstract, so it casts no vote on the map. It is linked to 3 registered trials, which are not on this map. Cited by 178 papers, 4 of them syntheses that pooled it.
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.
Personalized Health Education Against the Health Damage of COVID-19 Epidemic in Hungary (PROACTIVE-19)
The Value of Ultralow Dosis CT and Ultrasound in the Diagnosing of Pneumonia in the Emergency Department
Efficacy and Safety of Antimicrobial Stewardship Intervention in Hospitalized COVID-19 Patients: A Pragmatic Clinical Trial
Who cites it
178 citing papers in PubMed, 4 syntheses or guidelines pooled it.
- The prevalence of influenza bacterial co-infection and its role in disease severity: A systematic review and meta-analysis.Journal of global health · 2023Pooled it
- A systematic review on SARS-CoV-2-associated fungal coinfections.Journal of medical virology · 2022Pooled it
- Bacterial co-infection and secondary infection in patients with COVID-19: a living rapid review and meta-analysis.Clinical microbiology and infection : the official publication of the European Society of Clinical Microbiology and Infectious Diseases · 2020Pooled it
- Co-infections in people with COVID-19: a systematic review and meta-analysis.The Journal of infection · 2020Pooled it
- Prevalence and Outcomes of Bacterial Co-detections by Blood Culture Among Children and Adults Hospitalized With Laboratory-confirmed Influenza, Influenza Hospitalization Surveillance Network, 2022-2024.Clinical infectious diseases : an official publication of the Infectious Diseases Society of America · 2026Article
- Budget impact analysis of implementing point-of-care molecular testing for influenza A&B and RSV in Saudi older adult patients across hospital and home-care settings.Health economics review · 2026Article
- Using interpretable machine learning models to predict the occurrence of severe influenza in hospitalized children: a retrospective cohort study.BMC medical informatics and decision making · 2026Article
- Changing Epidemiology of Severe Pneumococcal Pneumonia in Adults at a Tertiary Hospital between 2010 and 2024.Tuberculosis and respiratory diseases · 2026Article
- Article
- Severe viral infections requiring intensive care unit admissions- aetiology, co-infections, respiratory interventions and outcomes.Infection · 2026Article
- Secondary fungal infections in severe acute viral diseases: clinical features and underlying immune mechanisms.Frontiers in microbiology · 2026Review
- Co-infection models ofFrontiers in cellular and infection microbiology · 2026Article
- Clinical features and outcomes of viral respiratory infections in adults during the 2023-2024 winter season.Scientific reports · 2025Observational
- RSV: an overview of infection in adults.Pneumonia (Nathan Qld.) · 2025Review
- Incidence Rates for InvasiveVaccines · 2025Article
- Timing of Influenza Antiviral Therapy and Risk of Death in Adults Hospitalized With Influenza-Associated Pneumonia, Influenza Hospitalization Surveillance Network (FluSurv-NET), 2012-2019.Clinical infectious diseases : an official publication of the Infectious Diseases Society of America · 2025Article
- Post-influenza bacterial infection: mechanisms of pathogenesis and advances in therapeutic strategies.Frontiers in microbiology · 2025Review
- Predicting Healthcare-Associated Infection in Patients with Pneumonia via QuantiFERONInfection and drug resistance · 2025Article
- Intranasal influenza-vectored vaccine expressing pneumococcal surface protein A protects against Influenza and Streptococcus pneumoniae infections.NPJ vaccines · 2024Article
- Orally Administered Lactobacilli Strains Modulate Alveolar Macrophages and Improve Protection Against Respiratory Superinfection.Biomolecules · 2024Article
118 more citing papers are in PubMed but not listed here.
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.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundThe aim of this study was to estimate the prevalence of pneumonia and secondary bacterial infections during the pandemic of influenza A(H1N1)pdm09.
methodsA systematic review was conducted to identify relevant literature in which clinical outcomes of pandemic influenza A(H1N1)pdm09 infection were described. Published studies (between 01/01/2009 and 05/07/2012) describing cases of fatal or hospitalised A(H1N1)pdm09 and including data on bacterial testing or co-infection.
resultsSeventy five studies met the inclusion criteria. Fatal cases with autopsy specimen testing were reported in 11 studies, in which any co-infection was identified in 23% of cases (Streptococcus pneumoniae 29%). Eleven studies reported bacterial co-infection among hospitalised cases of A(H1N1)2009pdm with confirmed pneumonia, with a mean of 19% positive for bacteria (Streptococcus pneumoniae 54%). Of 16 studies of intensive care unit (ICU) patients, bacterial co-infection identified in a mean of 19% of cases (Streptococcus pneumoniae 26%). The mean prevalence of bacterial co-infection was 12% in studies of hospitalised patients not requiring ICU (Streptococcus pneumoniae 33%) and 16% in studies of paediatric patients hospitalised in general or pediatric intensive care unit (PICU) wards (Streptococcus pneumoniae 16%).
conclusionWe found that few studies of the 2009 influenza pandemic reported on bacterial complications and testing. Of studies which did report on this, secondary bacterial infection was identified in almost one in four patients, with Streptococcus pneumoniae the most common bacteria identified. Bacterial complications were associated with serious outcomes such as death and admission to intensive care. Prevention and treatment of bacterial secondary infection should be an integral part of pandemic planning, and improved uptake of routine pneumococcal vaccination in adults with an indication may reduce the impact of a pandemic.
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.