A new flu virus found in pigs in China has become more infectious to humans and needs to be watched closely in case it becomes a potential “pandemic virus”, a new study has found.
A team of Chinese researchers looked at influenza viruses found in pigs from 2011 to 2018 and found a “G4” strain of H1N1 with “all the essential hallmarks of a candidate pandemic virus”, according to the paper, which was published in the US journal, Proceedings of the National Academy of Sciences (PNAS).
Workers on pig farms showed elevated levels of the virus in their blood, the authors said, adding that “close monitoring in human populations, especially the workers in the swine industry, should be urgently implemented.
“Pigs are intermediate hosts for the generation of pandemic influenza virus. Thus, systematic surveillance of influenza viruses in pigs is a key measure for prewarning the emergence of the next pandemic influenza,” the study said.
The peer-reviewed study was authored by academics at the China Agricultural University, Shandong Agricultural University, the Chinese Center for Disease Control and Prevention, the Chinese Academy of Sciences, and the University of Nottingham.
George Gao, Jinhua Liu, and colleagues isolated 179 viruses from pigs across 10 provinces in China from 2011 to 2018 to study the risks they pose to humans and found that since 2016 the majority of viruses found in farmed pigs exhibited features you’d expect from the populace during a pandemic.
According to the scientists, out of 300 samples taken from pig farmers on 15 different pig farms, only 10.4 per cent had antibodies against this strain of the virus.
This means the virus poses a particularly strong chance of pandemic spread according to the scientists.
‘All of this evidence indicates that G4 EA H1N1 virus is a growing problem in pig farms, and the widespread circulation of G4 viruses in pigs inevitably increases their exposure to humans,’ study authors wrote in their paper.