Beijing, June 30 (RHC)-- Researchers have discovered a new type of swine flu that has the potential to cause a pandemic, according to a study published in the US science journal PNAS.

The G4 flu is genetically descended from the H1N1 strain that was behind the pandemic in 2009.  G4 has "all the essential hallmarks of being highly adapted to infect humans," the researchers wrote.

They added that the G4 type was already predominant in pigs and that control of the infection in pigs and close monitoring of people working with the animals should be "urgently implemented."

The peer-reviewed study was authored by academics at the China Agricultural University, Shandong Agricultural University, Chinese Centers for Disease Control and Prevention, Chinese Academy of Sciences, and the University of Nottingham.