A study by the University of Hong Kong pointed out that the H9N2 A subtype and the recombinant virus strain of swine flu that appeared in China recently may be transmitted between humans and animals.Image: Taken from Twitter
In China, H9N2 avian influenza has recently appeared in pigs. According to a research article by the University of Hong Kong, the avian influenza virus is recombining with swine influenza virus, and the resulting virus strain has the possibility of human-animal transmission, warning that China and other regions need to continue to monitor the swine influenza virus.
An article titled “Natural Reassortment of Eurasian Avian-Like Swine H1N1 and Avian H9N2 Influenza Viruses in Pigs, China” published by the School of Public Health of the University of Hong Kong states that researchers collected 829 Swine nasal swab samples were used to isolate eight Influenza A viruses for comparison.
It was found that the A stream detected in August 2021 was the H3N2 subtype, and its internal gene segments were all from the H1N1 A subtype lineage.
The influenza A virus isolated in September 2021 is a reassortment between multiple swine flu lineages. A part of the gene segment of the virus belongs to the avian H9N2 virus subtype, including gene segments from the pH1N1 lineage and the Eurasian avian H1N1 lineage, and its non-structural gene segments belong to the triple reassortment lineage.
Based on previous studies, genotype 4 Eurasian avian-like influenza A virus can bind to human sialic acid receptors, enabling the virus to replicate efficiently in human respiratory epithelial cells. Sequence analysis indicated that some previously reported genotype 4 viruses and the Eurasian avian-like H1N1 virus isolated in this study may share a common ancestor, cautioning that further risk assessment of this genotype and its recombination epidemic potential should be conducted.
In addition, avian influenza A viruses associated with human infection contain internal genes derived from the H9N2 subtype virus, which studies suggest may contribute to zoonotic infection.
