Cross-species spill-over potential of the H9N2 bat influenza A virus

Nat Commun. 2024 Apr 25;15(1):3449. doi: 10.1038/s41467-024-47635-4.

Abstract

In 2017, a novel influenza A virus (IAV) was isolated from an Egyptian fruit bat. In contrast to other bat influenza viruses, the virus was related to avian A(H9N2) viruses and was probably the result of a bird-to-bat transmission event. To determine the cross-species spill-over potential, we biologically characterize features of A/bat/Egypt/381OP/2017(H9N2). The virus has a pH inactivation profile and neuraminidase activity similar to those of human-adapted IAVs. Despite the virus having an avian virus-like preference for α2,3 sialic acid receptors, it is unable to replicate in male mallard ducks; however, it readily infects ex-vivo human respiratory cell cultures and replicates in the lungs of female mice. A/bat/Egypt/381OP/2017 replicates in the upper respiratory tract of experimentally-infected male ferrets featuring direct-contact and airborne transmission. These data suggest that the bat A(H9N2) virus has features associated with increased risk to humans without a shift to a preference for α2,6 sialic acid receptors.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Chiroptera* / virology
  • Ducks* / virology
  • Female
  • Ferrets* / virology
  • Humans
  • Influenza A Virus, H9N2 Subtype* / isolation & purification
  • Influenza A Virus, H9N2 Subtype* / pathogenicity
  • Influenza A Virus, H9N2 Subtype* / physiology
  • Influenza in Birds / transmission
  • Influenza in Birds / virology
  • Influenza, Human / transmission
  • Influenza, Human / virology
  • Lung / virology
  • Male
  • Mice
  • Neuraminidase / metabolism
  • Orthomyxoviridae Infections* / transmission
  • Orthomyxoviridae Infections* / virology
  • Receptors, Cell Surface*
  • Virus Replication

Substances

  • Neuraminidase
  • sialic acid receptor
  • Receptors, Cell Surface