Reverse zoonosis of influenza to swine: new perspectives on the human-animal interface

Trends Microbiol. 2015 Mar;23(3):142-53. doi: 10.1016/j.tim.2014.12.002. Epub 2015 Jan 4.

Abstract

The origins of the 2009 influenza A (H1N1) pandemic in swine are unknown, highlighting gaps in our understanding of influenza A virus (IAV) ecology and evolution. We review how recently strengthened influenza virus surveillance in pigs has revealed that influenza virus transmission from humans to swine is far more frequent than swine-to-human zoonosis, and is central in seeding swine globally with new viral diversity. The scale of global human-to-swine transmission represents the largest 'reverse zoonosis' of a pathogen documented to date. Overcoming the bias towards perceiving swine as sources of human viruses, rather than recipients, is key to understanding how the bidirectional nature of the human-animal interface produces influenza threats to both hosts.

Keywords: evolution; human–animal interface; influenza A virus; pandemic; swine.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Review

MeSH terms

  • Animals
  • Humans
  • Influenza A Virus, H1N1 Subtype / pathogenicity
  • Influenza A virus* / genetics
  • Influenza A virus* / pathogenicity
  • Influenza, Human / transmission*
  • Influenza, Human / virology
  • Orthomyxoviridae Infections / epidemiology
  • Orthomyxoviridae Infections / transmission
  • Orthomyxoviridae Infections / veterinary*
  • Orthomyxoviridae Infections / virology
  • Phylogeny
  • Swine
  • Swine Diseases / epidemiology*
  • Swine Diseases / transmission*
  • Swine Diseases / virology
  • Zoonoses