Researchers in China discovered a new type of swine flu that is capable of triggering a pandemic, according to a study published Monday in the American scientific journal PNAS. Called G4, it genetically descends from H1N1 strain that 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.
The World Health Organization said Tuesday it would “carefully read” the study on the new virus, and a spokesman said the findings highlighted the importance of the world not lowering “its guard over the flu.”
The global medical community must “be vigilant and continue surveillance, including in the
coronavirus pandemic“WHO representative Christian Lindmeier said Tuesday in Geneva.
From 2011 to 2018, researchers took 30,000 pig nasal swabs at slaughterhouses in 10 Chinese provinces and at a veterinary hospital, allowing them to isolate 179 swine flu viruses. Most were of a new type that has been dominant among pigs since 2016.
The researchers then conducted several experiments, including on ferrets, which are widely used in flu studies because they experience human-like symptoms, primarily fever, cough, and sneeze.
G4 was found to be highly infectious, replicated in human cells, and caused more severe symptoms in ferrets than other viruses. The tests also showed that any immunity that humans get from exposure to seasonal flu does not provide protection against G4.
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According to blood tests that showed antibodies created by exposure to the virus, 10.4 percent of pig workers had already been infected. Tests showed that up to 4.4 percent of the general population also appeared to have been exposed.
Therefore, the virus has already passed from animals to humans, but there is still no evidence that it can be transmitted from human to human, the scientists’ main concern.
“It is concerning that human G4 virus infection promotes human adaptation and increases the risk of a human pandemic,” the researchers wrote.
When asked about the virus on Tuesday, Chinese Foreign Ministry spokesman Zhao Lijian told a press conference that China “has been paying close attention to its development” and will take all necessary steps to prevent its spread. spread and any outbreaks.
The study authors called for urgent measures to control people who work with pigs.
“The work comes as a healthy reminder that we are constantly at risk of a new emergence of zoonotic pathogens and that farm animals, with which humans have more contact than wildlife, may act as a source of major viruses. pandemics, “said James Wood. head of the department of veterinary medicine at Cambridge University.
A zoonotic infection is caused by a pathogen that has jumped from a non-human animal to a human.
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