Chinese researchers have discovered a new type of swine flu capable of triggering a pandemic, according to a study published Monday in the American scientific journal PNAS.
Called G4, it is genetically derived from the H1N1 strain which caused a pandemic in 2009.
It has “all the essential characteristics of being highly adapted to infect humans,” say the authors, scientists from Chinese universities and the China Center for Disease Control and Prevention.
From 2011 to 2018, researchers collected 30,000 pig nasal swabs from abattoirs in 10 Chinese provinces and a veterinary hospital, allowing them to isolate 179 swine flu viruses.
The majority were of a new type that has dominated in pigs since 2016.
The researchers then performed various experiments, including on ferrets, which are widely used in influenza studies because they have symptoms similar to those in humans – mainly fever, cough, and sneezing.
G4 has been shown to be highly infectious, replicating in human cells and causing more severe symptoms in ferrets than other viruses.
Tests have also shown that the immunity humans gain from exposure to seasonal flu does not protect against G4.
According to blood tests that revealed antibodies created by exposure to the virus, 10.4% of pig workers had already been infected.
Tests have shown that up to 4.4% of the general population also appears to have been exposed.
The virus has therefore already passed from animal to human, but there is no evidence yet that it can be transmitted from human to human – the main concern of scientists.
“There is concern that human infection with the G4 virus will promote human adaptation and increase the risk of a human pandemic,” the researchers wrote.
The authors called for urgent measures to monitor people working with pigs.
“This work is a salutary reminder that we are constantly threatened by a new emergence of zoonotic pathogens and that farm animals, with which humans are more in contact than with wildlife, can act as the source of important pandemic viruses, “said James Wood, head of the department of veterinary medicine at the University of Cambridge.
A zoonotic infection is caused by a pathogen that has passed from a non-human animal to a human.
(With the exception of the title, this story was not edited by GalacticGaming staff and is published from a syndicated feed.)