ArticlePloS one2015
Impact of the 2009 H1N1 Pandemic on Age-Specific Epidemic Curves of Other Respiratory Viruses: A Comparison of Pre-Pandemic, Pandemic and Post-Pandemic Periods in a Subtropical City.
Article in PloS one, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. An erratum has been issued. It is linked to trial NCT05126641 (Analysis of Emergency Department Visits According to Incidence of Covid-19 in French Metropolis), which is not on this map. Cited by 23 papers, 1 of them a synthesis 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.
Analysis of Emergency Department Visits According to Incidence of Covid-19 in French Metropolis : a One-year Multicenter Observational Retrospective Study.
Who cites it
23 citing papers in PubMed, 1 synthesis or guideline pooled it.
- The impact of the 2009 influenza pandemic on the seasonality of human respiratory syncytial virus: A systematic analysis.Influenza and other respiratory viruses · 2021Pooled it
- Changes to Endemic Respiratory Virus Circulation and Testing Before, During, and After the COVID-19 Pandemic.Open forum infectious diseases · 2025Article
- Unraveling the role of viral interference in disrupting biennial RSV epidemics in northern Stockholm.Nature communications · 2025Article
- The Role of Viral Interference in Shaping RSV Epidemics Following the 2009 H1N1 Influenza Pandemic.Influenza and other respiratory viruses · 2025Article
- Trends of respiratory viruses and factors associated with severe acute respiratory infection in patients presenting at a university hospital: a 6-year retrospective study across the COVID-19 pandemic.Frontiers in public health · 2025Article
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- Change in patterns of hospitalization for influenza during COVID-19 surges.Influenza and other respiratory viruses · 2022Article
- Epidemiology of influenza in Ghana, 2011 to 2019.PLOS global public health · 2022Article
- Surveillance of seasonal respiratory viruses among Chilean patients during the COVID-19 pandemic.Health science reports · 2021Article
- Comparison of Common Respiratory Virus Peak Incidence Among Varying Age Groups in Rhode Island, 2012-2016.JAMA network open · 2020Article
- Overview of seasonal influenza and recommended vaccine during the 2016/2017 season in Nepal.Heliyon · 2020Article
- Evidence for Cross-Protection Against Subsequent Febrile Respiratory Illness Episodes From Prior Infections by Different Viruses Among Singapore Military Recruits 2009-2014.The Journal of infectious diseases · 2019Article
- Temporal patterns of influenza A subtypes and B lineages across age in a subtropical city, during pre-pandemic, pandemic, and post-pandemic seasons.BMC infectious diseases · 2019Article
- Association of meteorological factors with seasonal activity of influenza A subtypes and B lineages in subtropical western China.Epidemiology and infection · 2019Article
- Investigating Viral Interference Between Influenza A Virus and Human Respiratory Syncytial Virus in a Ferret Model of Infection.The Journal of infectious diseases · 2018Article
- Influenza interaction with cocirculating pathogens and its impact on surveillance, pathogenesis, and epidemic profile: A key role for mathematical modelling.PLoS pathogens · 2018Review
- Evidence for Viral Interference and Cross-reactive Protective Immunity Between Influenza B Virus Lineages.The Journal of infectious diseases · 2018Article
- The high frequency of non-aspartic acid residues at HA222 in influenza A(H1N1) 2009 pandemic viruses is associated with mortality during the upsurge of 2015: a molecular and epidemiological study from central India.Epidemiology and infection · 2017Article
- Article
- Extensive multiplex PCR diagnostics reveal new insights into the epidemiology of viral respiratory infections.Epidemiology and infection · 2016Article
Corrections and comments
- Erratum issued
Authors and funding
9 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundThe 2009 H1N1 influenza pandemic caused offseason peaks in temperate regions but coincided with the summer epidemic of seasonal influenza and other common respiratory viruses in subtropical Hong Kong. This study was aimed to investigate the impact of the pandemic on age-specific epidemic curves of other respiratory viruses.
methodsWeekly laboratory-confirmed cases of influenza A (subtypes seasonal A(H1N1), A(H3N2), pandemic virus A(H1N1)pdm09), influenza B, respiratory syncytial virus (RSV), adenovirus and parainfluenza were obtained from 2004 to 2013. Age-specific epidemic curves of viruses other than A(H1N1)pdm09 were compared between the pre-pandemic (May 2004-April 2009), pandemic (May 2009-April 2010) and post-pandemic periods (May 2010-April 2013).
resultsThere were two peaks of A(H1N1)pdm09 in Hong Kong, the first in September 2009 and the second in February 2011. The infection rate was found highest in young children in both waves, but markedly fewer cases in school children were recorded in the second wave than in the first wave. Positive proportions of viruses other than A(H1N1)pdm09 markedly decreased in all age groups during the first pandemic wave. After the first wave of the pandemic, the positive proportion of A(H3N2) increased, but those of B and RSV remained slightly lower than their pre-pandemic proportions. Changes in seasonal pattern and epidemic peak time were also observed, but inconsistent across virus-age groups.
conclusionOur findings provide some evidence that age distribution, seasonal pattern and peak time of other respiratory viruses have changed since the pandemic. These changes could be the result of immune interference and changing health seeking behavior, but the mechanism behind still needs further investigations.
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