Journal Article

Long-term co-circulation of multiple influenza A viruses in pigs, Guangxi, China

García-Sastre, Adolfo, Huang, Jiamo, Wei, Zuzhang, Yu, Liangzheng, Guo, Xuan, Zeng, Yongfang, Qin, Yifeng, Chen, Ying, Xu, Yi, Ouyang, Kang, Huang, Chongqiang, Qin, Yibin, Huang, Weijian

2024

Overview

Influenza A viruses (IAVs) pose a persistent potential threat to human health because of the spillover from avian and swine infections. Extensive surveillance was performed in 12 cities of Guangxi, China, during 2018 and 2023. A total of 2,540 samples (including 2,353 nasal swabs and 187 lung tissues) were collected from 18 pig farms with outbreaks of respiratory disease. From these, 192 IAV-positive samples and 19 genomic sequences were obtained. We found that the H1 and H3 swine influenza A viruses (swIAVs) of multiple lineages and genotypes have continued to co-cirulate during that time in this region. Genomic analysis revealed the Eurasian avian-like H1N1 swIAVs (G4) still remained predominant in pig populations. Strikingly, the novel multiple H3N2 genotypes were found to have been generated through repeated introduction of the early H3N2 North American triple reassortant viruses (TR H3N2 lineage) that emerged in USA and Canada in 1998 and 2005, respectivley. Notably, when the matrix gene segment derived from H9N2 avian influenza virus was introduced into endemic swIAVs, this produced a novel quadruple reassortant H1N2 swIAV that could pose a potential risk for zoonotic infection.

• Publisher: Taylor & Francis Ltd,Taylor & Francis,Taylor & Francis Group
• Subject: Emerging Seasonal and Pandemic Influenza Infections / Eurasian avian-like H1N1 and human-like H3N2 / H9N2 avian influenza virus / Hogs / Influenza / multiple reassortment / pandemic potential / Swine influenza virus / Viruses