Why are pigs considered so important in relation to the evolution of influenza A viruses?
In general – although not always the case – pigs can be susceptible to influenza A viruses established in avian, human, and pig populations; therefore they have the potential to become co-infected with human, avian, and swine influenza viruses. A co-infection with several different influenza A viruses can lead through exchange of genetic material between the viruses (reassortment) to the emergence of a new antigenically distinct virus (a reassortant strain) with pandemic potential.
