The virus is called G4 and is genetically descended from the H1N1 strain that caused a pandemic in 2009.
By:
AFP
–
–
Researchers discovered in China a new strain of the swine flu virus with all the characteristics capable of causing a future pandemic, according to a study published Monday, June 29 in the American scientific journal Pnas.
The virus is called G4 and it genetically descends from the H1N1 strain that caused a pandemic in 2009: “It has all the essential traits that show high adaptability to infect humans,” wrote the authors, scientists from Chinese universities and the Prevention Center. and Chinese Disease Control.
The work presented is voluminous: from 2011 to 2018, 30,000 samples were taken with nasal swabs from pigs in slaughterhouses in 10 Chinese provinces and in a veterinary hospital, which allowed the isolation of 179 swine flu viruses.
Most were of the new variety, which has become dominant in pigs since 2016.
From there, the researchers carried out various laboratory experiments with ferrets, animals widely used in influenza research because their symptoms are comparable to those of humans: they have a fever, cough and sneeze.
They found that G4 viruses were more infectious, replicated in human cells, and caused more severe symptoms in ferrets than other strains.
Furthermore, it was found with in vitro tests that the immunity obtained after contact with human seasonal influenza viruses does not protect against G4.
The other bad news is that a relatively high number of workers who have regular contact with pigs had been infected, 10.4%, according to blood tests that detected the presence of antibodies against the virus.
4.4% of the general population also appeared to be infected.
Therefore, the virus has already spread to humans, scientists say, but there is no evidence that it can be transmitted from human to human. That is precisely his current fear.
“Pandemics occur when influenza A viruses with a new HA surface antigen become capable of human-to-human transmission,” the researchers concluded.
“The concern is that human G4 virus infections do not lead to human adaptation and increase the risk of a human pandemic.”
It is urgent, they say, to implement surveillance of populations that work in contact with pigs.
“The study is a healthy reminder that we are constantly at risk of developing zoonotic pathogens, and that farm animals, with which humans are more in contact than wild animals, are the source of major pandemic viruses.” said James Wood, head of the department of veterinary medicine at the University of Cambridge.
Asked about this virus, a spokesman for the Chinese Foreign Ministry said Tuesday during a regular press conference that China “is paying particular attention to its development” and will take the necessary steps to contain its spread.
–
