Avian-origin influenza A(H7N9) infection in influenza A(H7N9)-affected areas of China: a serological study

J Infect Dis. 2014 Jan 15;209(2):265-9. doi: 10.1093/infdis/jit430. Epub 2013 Aug 9.


Serological surveillance conducted in areas of an outbreak of influenza A(H7N9) infection in China found no seropositivity for antibodies specific for avian-origin influenza A(H7N9) among 1129 individuals of the general population, whereas >6% of 396 poultry workers were positive (on the basis of a hemagglutination inhibition titer of ≥ 80) for this subtype, confirming that infected poultry is the principal source of human infections and that subclinical infections are possible. Fourteen days after symptom onset, elevated levels of antibodies to A(H7N9) were found in 65.8% of patients (25/38) who survived but in only 28.6% of those (2/7) who died, suggesting that the presence of antibodies may improve clinical outcome in infected patients.

Keywords: H1N1; H7N9; antibodies; influenza; poultry workers; serological surveillance.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Antibodies, Viral / blood
  • Child
  • Child, Preschool
  • China / epidemiology
  • Female
  • Hemagglutination Inhibition Tests
  • Humans
  • Infant
  • Influenza A Virus, H7N9 Subtype / isolation & purification*
  • Influenza, Human / epidemiology*
  • Influenza, Human / immunology
  • Influenza, Human / virology*
  • Male
  • Middle Aged
  • Occupational Exposure*
  • Seroepidemiologic Studies
  • Survival Analysis
  • Young Adult


  • Antibodies, Viral