Identification of Human H1N2 and Human-Swine Reassortant H1N2 and H1N1 Influenza A Viruses among Pigs in Ontario, Canada (2003 to 2005)

Since 2003, three novel genotypes of H1 influenza viruses have been recovered from Canadian pigs, including a wholly human H1N2 virus and human-swine reassortants. These isolates demonstrate that human-lineage H1N2 viruses are infectious for pigs and that viruses with a human PB1/swine PA/swine PB2 polymerase complex can replicate in pigs.