Scientists have discovered a new swine flu pathogen in China.

Jun 30, 2020
Scientists have discovered a new swine flu pathogen in China. G4 is said to be highly infectious - and transferable to humans.

G4 (full name: G4 EA H1N1) is derived from the H1N1 virus that triggered the swine flu pandemic in 2009. For the study published in the US journal "PNAS", researchers from several Chinese universities and the Chinese Center for Disease Control and Prevention took around 30,000 swabs from pigs in slaughterhouses in ten Chinese provinces between 2011 and 2018. 179 different swine flu viruses were isolated. Most of them were of a new species, which has increased in pigs since 2016.

No protection from seasonal flu
The researchers then carried out experiments on ferrets, among other things, which are used in flu studies because they have symptoms similar to those of humans. It has been observed that G4 is highly infectious, multiplies in human cells and causes more severe symptoms in ferrets than other viruses.

Tests also showed that any immunity people gain from seasonal flu does not protect against G4. According to the scientists, 10.4 percent of the pig farmers were already infected. 4.4 percent of the population were also exposed to the virus, the researchers found through antibody tests.

The main concern of the scientists is that the virus can be transmitted from person to person. It is worrying that the pathogen adapts to humans and thus increases the risk of a pandemic in humans, the researchers wrote. Although the new virus is capable of infecting humans, there is no immediate risk of a new pandemic, said biologist Carl Bergstrom of the University of Washington, who was not involved in the study. "There is no evidence that G4 circulates in humans despite five years of intense exposure," he said on Twitter.

Farm animals as a source of pandemics
The study was "a reminder that we are constantly at risk of reoccurrence of zoonotic pathogens and that livestock with which humans have more contact than wildlife can serve as a source of major pandemic viruses," said James Wood, director of the Department of Veterinary Medicine at Cambridge University in the UK. A zoonotic infection is caused by a pathogen that has jumped from an animal to a human.

When asked about the research results, Chinese Foreign Ministry spokesman Zhao Lijian said on Tuesday that China has been closely monitoring this development and will take all necessary measures to prevent the virus from spreading. The study authors call for regular examinations of people who work with pigs.

Sign in
Forgot your password? Remind