Genetic characterization of a novel quadruple reassortant influenza A (H1N2) virus from swine, China, 2021

We read with interest a recent letter in the Journal of Infection, which reported the emergence of novel H5N6 reassortant and it's threat to both birds and humans.1 Pigs are susceptible to human, swine, and avian influenza A viruses (IAVs) and considered as intermediate hosts or “mixing vessels” for generating novel viruses with pandemic potential.2 Moreover, China has a complicated ecosystem of swine influenza viruses (SIVs) in which H1N1, H1N2, and H3N2 subtypes with classical swine (CS), North America triple-reassortant (TR), Eurasian avian-like (EA), and H1N1 pandemic/2009 (pdm/09) lineages are co-circulating throughout the swine population.