Avian influenza viruses (AIVs) are classified as either low pathogenicity (LP; generally causing sub-clinical to mild infections) or high pathogenicity (HP; capable of causing significant mortality events in birds). To date, HPAIVs appear o be restricted to the haemagglutinin (HA) glycoprotein H5 and H7 AIV subtypes. Both LPAIV and HPAIV H5 and H7 AIV subtypes are classified as the causative agents of notifiable disease in poultry. A broad range of non-H5/non-H7 LPAIVs also exist that have been associated with more severe disease outcomes in avian species. As a result, the constant threat from AIVs causes significant economic damage in poultry production systems worldwide. The close proximity between mammalian and susceptible avian species in some environments provides the opportunity for both inter-host transmission and mammalian adaptation, potentially resulting in novel AIV strains capable of infecting humans.

This study was supported by the:
  • Animal Health and Veterinary Laboratories Agency (Award SV3400)
    • Principle Award Recipient: RowenaDE Hansen
  • Horizon 2020 Framework Programme (Award 727922)
    • Principle Award Recipient: AshleyCharles Banyard
  • Animal Health and Veterinary Laboratories Agency (Award SV3006)
    • Principle Award Recipient: AshleyCharles Banyard
  • Department for Environment, Food and Rural Affairs (Award SE2213)
    • Principle Award Recipient: AshleyCharles Banyard
  • This is an open-access article distributed under the terms of the Creative Commons Attribution License. This article was made open access via a Publish and Read agreement between the Microbiology Society and the corresponding author’s institution.

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