Vaccine immune pressure influences viral population complexity of avian influenza virus during infection

Vet Microbiol. 2017 May;203:88-94. doi: 10.1016/j.vetmic.2017.02.016. Epub 2017 Feb 27.


Vaccines are useful tools to control influenza A virus infection in poultry, but they need to be periodically reformulated to guarantee appropriate protection from infection and to limit viral replication and circulation, which could favour the emergence of new variants. In this study, a deep sequencing approach was used to characterize and follow the evolution of the hemagglutinin of the H5N1 highly pathogenic avian influenza viral population in infected animals vaccinated with two vaccines conferring different protection levels. Results from this preliminary investigation suggested that the evolution of the viral population, as well as the abundance and heterogeneity of minority variants could be influenced by the immune pressure conferred by vaccination.

Keywords: Deep sequencing; Evolution; H5N1; Influenza A virus; Vaccine.

MeSH terms

  • Animals
  • Genetic Variation
  • Hemagglutinins / genetics*
  • High-Throughput Nucleotide Sequencing / veterinary
  • Influenza A Virus, H5N1 Subtype / genetics*
  • Influenza A Virus, H5N1 Subtype / immunology
  • Influenza A Virus, H5N1 Subtype / isolation & purification
  • Influenza Vaccines / immunology*
  • Influenza in Birds / virology*
  • Poultry
  • Poultry Diseases / virology*
  • Vaccination / veterinary*


  • Hemagglutinins
  • Influenza Vaccines