A new strain of Swine flu has been discovered in China which has the capability of causing a pandemic, according according to a study in the US science journal PNAS. The findings come after scientists collected 30,000 nose swabs in slaughterhouses in 10 Chinese provinces between 2011 and 2018. The researchers were able to isolate 179 swine flu viruses, many of which were already known. However, a new strain called G4 has been discovered. G4 is genetically descended from the H1N1 strain that caused a pandemic in 2009.
It possesses “all the essential hallmarks of being highly adapted to infect humans”, said the authors, scientists at Chinese universities and China’s Center for Disease Control and Prevention, in the study published on Monday.
G4 was observed to be highly infectious, replicating in human cells and causing more serious symptoms in lab animal experimentation. Seasonal immunities developed from the flu strain provide no protection against the virus.
1 in 10 swine workers had tested positive for antibodies. The tests also showed that as many as 4.4% of the general population also appeared to have been exposed.
Chinese Foreign Ministry spokesman Zhao Lijian told a daily news conference on Tuesday that China was closely following developments. “We will take all necessary measures to prevent the spread and outbreak of any virus,” he said.
Right now, there is no evidence that the virus has the ability to pass from human to human, which is the chief concern for scientists and medical professionals. “It is of concern that human infection of G4 virus will further human adaptation and increase the risk of a human pandemic,” the researchers wrote.
James Wood, head of the department of veterinary medicine at Cambridge University, said: “The work comes as a salutary reminder that we are constantly at risk of new emergence of zoonotic pathogens and that farmed animals – with which humans have greater contact than with wildlife – may act as the source for important pandemic viruses.”