ArticleInfluenza and other respiratory viruses2017
Sero-epidemiologic study of influenza A(H7N9) infection among exposed populations, China 2013-2014.
Article in Influenza and other respiratory viruses, 2017. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 13 papers, 2 of them syntheses that pooled it.
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Who cites it
13 citing papers in PubMed, 2 syntheses or guidelines pooled it, 18 citations in OpenAlex.
- Serological Evidence of Human Infection With Avian Influenza A(H7N9) Virus: A Systematic Review and Meta-analysis.The Journal of infectious diseases · 2022Pooled it
- Seroprevalence of H7N9 infection among humans: A systematic review and meta-analysis.Influenza and other respiratory viruses · 2020Pooled it
- Occupational Risk from Avian Influenza Viruses at Different Ecological Interfaces Between 1997 and 2019.Microorganisms · 2025Review
- Biological Sex and Pregnancy Affect Influenza Pathogenesis and Vaccination.Current topics in microbiology and immunology · 2023Article
- Anamnestic broadly reactive antibodies induced by H7N9 virus more efficiently bind to seasonal H3N2 strains.Human vaccines & immunotherapeutics · 2022Article
- Novel Avian Influenza A Virus Infections of Humans.Infectious disease clinics of North America · 2019Review
- Avian Influenza A Virus Infection among Workers at Live Poultry Markets, China, 2013-2016.Emerging infectious diseases · 2018Article
- Influenza A(H7N9) Virus Antibody Responses in Survivors 1 Year after Infection, China, 2017.Emerging infectious diseases · 2018Article
- Evaluation of animal-to-human and human-to-human transmission of influenza A (H7N9) virus in China, 2013-15.Scientific reports · 2018Article
- Sero-epidemiologic study of influenza A(H7N9) infection among exposed populations, China 2013-2014.Influenza and other respiratory viruses · 2017Article
- Article
- C-C Motif Chemokine Ligand 2 (CCL2) Mediates Acute Lung Injury Induced by Lethal Influenza H7N9 Virus.Frontiers in microbiology · 2017Article
- From H5N1 to HxNy: An epidemiologic overview of human infections with avian influenza in the Western Pacific Region, 2003-2017.Western Pacific surveillance and response journal : WPSARArticle
Corrections and comments
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Authors and funding
25 authors at 15 institutions in 3 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundThe first human infections of novel avian influenza A(H7N9) virus were identified in China in March 2013. Sentinel surveillance systems and contact tracing may not identify mild and asymptomatic human infections of influenza A(H7N9) virus.
objectivesWe assessed the seroprevalence of antibodies to influenza A(H7N9) virus in three populations during the early stages of the epidemic. PATIENTS/
methodsFrom March 2013 to May 2014, we collected sera from the general population, poultry workers, and contacts of confirmed infections in nine Chinese provinces reporting human A(H7N9) infections and, for contacts, second sera 2-3 weeks later. We screened for A(H7N9) antibodies by advanced hemagglutination inhibition (HI) assay and tested sera with HI titers ≥20 by modified microneutralization (MN) assay. MN titers ≥20 or fourfold increases in paired sera were considered seropositive.
resultsAmong general population sera (n=1480), none were seropositive. Among poultry worker sera (n=1866), 28 had HI titers ≥20; two (0.11%, 95% CI: 0.02-0.44) were positive by MN. Among 61 healthcare and 117 non-healthcare contacts' sera, five had HI titers ≥20, and all were negative by MN. There was no seroconversion among 131 paired sera.
conclusionsThere was no evidence of widespread transmission of influenza A(H7N9) virus during March 2013 to May 2014, although A(H7N9) may have caused rare, previously unrecognized infections among poultry workers. Although the findings suggest that there were few undetected cases of influenza A(H7N9) early in the epidemic, it is important to continue monitoring transmission as virus and epidemic evolve.
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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.