Higher virulence of swine H1N2 influenza viruses containing avian-origin HA and 2009 pandemic PA and NP in pigs and mice

Abstract

Pigs are capable of harbouring influenza A viruses of human and avian origin in their respiratory tracts and thus act as an important intermediary host to generate novel influenza viruses with pandemic potential by genetic reassortment between the two viruses. Here, we show that two distinct H1N2 swine influenza viruses contain avian-like or classical swine-like hemagglutinins with polymerase acidic (PA) and nucleoprotein (NP) genes from 2009 pandemic H1N1 influenza viruses that were found to be circulating in Korean pigs in 2018. Swine H1N2 influenza virus containing an avian-like hemagglutinin gene had enhanced pathogenicity, causing severe interstitial pneumonia in infected pigs and mice. The mortality rate of mice infected with swine H1N2 influenza virus containing an avian-like hemagglutinin gene was higher by 100% when compared to that of mice infected with swine H1N2 influenza virus harbouring classical swine-like hemagglutinin. Further, chemokines attracting inflammatory cells were strongly induced in lung tissues of pigs and mice infected by swine H1N2 influenza virus containing an avian-like hemagglutinin gene. In conclusion, it is necessary for the well-being of humans and pigs to closely monitor swine influenza viruses containing avian-like hemagglutinin with PA and NP genes from 2009 pandemic H1N1 influenza viruses.

The evolution, pathogenicity and transmissibility of quadruple reassortant H1N2 swine influenza virus in China: A potential threat to public health

“…Swine H1N2 influenza viruses carrying avian-origin HA and 2009 pandemic PA and NP genes exhibited higher virulence in pigs and mice ( Jang et al., 2020 ). Based on the analysis above, the PB2 , PB1 , NP , NA , and NS genes of SW/198/20 showed high homology with human influenza strains.…”

Der Porcine Respiratory Disease Complex (PRDC) – eine klinische Übersicht

“…Dies ist insbesondere im Hinblick auf die von Nathues et al 11 nachgewiesene große genetische Variabilität von M. hyopneumoniae -Stämmen sowohl auf Einzeltier- als auch auf Bestandsebene von Bedeutung. Auch für PRRSV 12 , 13 , 14 und IAV 15 , 16 ließ sich ein Zusammenhang zwischen Isolat und Virulenz ermitteln. Bei PCV2 wird ein Zusammenhang zwischen Genotypen bzw.…”

Ecological and evolutionary dynamics of multi-strain RNA viruses

“…These processes may ultimately shape the temporal and spatial distribution of viral genetic diversity across multiple scales, particularly when there are underlying spatiotemporal heterogeneities in the susceptibility of hosts as a result of previous patterns of viral circulation. The challenges in controlling influenza A in swine due to vaccine inefficacies and emergence of distinct divergent viral communities attributed to viral 'mixing' in pigs are a good example of the potential benefits of understanding multi-strain dynamics of viruses [6][7][8][9] .…”