Molecular evolution of H1N1 swine influenza in Guangdong, China, 2016–2017

The R251K Substitution in Viral Protein PB2 Increases Viral Replication and Pathogenicity of Eurasian Avian-like H1N1 Swine Influenza Viruses

“…The two viruses A/swine/Guangdong/YJ4/2014 (YJ4 (H1N1)) and A/swine/Guangdong/MS285/2017 (MS285 (H1N1)) have been previously described (GISAID accession numbers EPI_ISL_249797 and EPI_ISL_293281, respectively) [28,29]. The viruses were amplified in Madin-Darby canine kidney cells (MDCK; ATCC, Manassas, VA, USA) at 37 • C, and the obtained viruses were collected and stored at −80 • C until use in experiments.…”

“…However, compared with molecular pathogenic determinants known for avian and human influenza viruses, little has been known for swine influenza virus, especially for EA H1N1 virus. To investigate molecular pathogenic determinants of EA H1N1 virus, we compared the mouse pathogenicity of A/swine/Guangdong/YJ4/2014 (YJ4) [28] and A/swine/Guangdong/MS285/2017 (MS285) [29], belonging to the HuN-like virus, which is the main genotype causing human infections [16], and a new pathogenic determinant of EA H1N1 virus was identified by further analysis of a series of reassortant and mutant viruses.…”

Persistence of pdm2009-H1N1 internal genes of swine influenza in pigs, Thailand

“…Our result supported the reassortment or multiple-reassortment between endemic Thai-S-IAVs and pdmH1N1-2009. Reassortment of swine influenza viruses have been observed worldwide such as in China 22,23 , Europe 24 and America [25][26][27] . www.nature.com/scientificreports/ Based on genetic analysis, the transmission of human-origin viruses to pigs could contribute the adaptations or mutations for the fitness of the viruses.…”

A novel reassortant influenza A (H1N1) virus infection in swine in Shandong Province, eastern China

“…Furthermore, there are some reports describing previous swine H1N1 reassortant viruses isolated from pigs in China (Bi et al, ; Cai et al, ; He et al, ; Sun et al, ; Xu et al, ). For example, some swine reassortant influenza viruses possessing H1N1 swine influenza virus genes (HA, NA and NS) and H1N1 human influenza virus genes (PB2, PB1, PA, NP and M) were found in pigs in Guangxi Province and Guangdong Province in China (Cai et al, ; He et al, ); several swine reassortant influenza viruses possessing swine influenza virus genes (HA, NA, M and NS) and H1N1 human influenza virus genes (PB2, PB1, PA and NP) were found in pigs in Tianjin city in China (Sun et al, ); one swine reassortant influenza virus possessing H1N2 avian influenza virus genes (PB2 and PA), H1N1 avian influenza virus genes (HA, NA and M), H1N2 human influenza virus gene (PB1), and H1N2 swine influenza virus genes (NP and NS) were found in pigs in Guangdong Province in China (Xu et al, ); one swine reassortant influenza virus possessing H9N2 avian influenza virus gene (PB1) and swine influenza virus genes (PB2, PA, HA, NP, NA, M and NS) was found in pigs in Shandong Province in China (Bi et al, ). Here, we report a novel reassortant H1N1 virus possessing swine influenza virus genes (PA, HA, NP, NA and NS) and human influenza virus genes (PB2, PB1 and M) and the prevalence of the swine influenza virus containing the HA gene of this novel reassortant virus in swine herds in Shandong Province, eastern China (Appendix Figure S1).…”

“…Therefore, continuous monitoring of the influenza A (H1N1) virus will help us better prevent H1N1 virus pandemics. However, there are few reports about the prevalence status of H1N1 virus in China (Cai et al, ; Qi et al, ). Here, we isolated a novel reassortant influenza A (H1N1) virus generated by reassortment between human 2009 pandemic influenza A (H1N1) viruses and swine influenza viruses; furthermore, extensive specific seroconversion against this novel reassortant H1N1 virus was detected in numerous swine farms in Shandong Province, which is a large pig‐raising province in eastern China.…”