researchers have discovered a strain of swine influenza virus in China, presenting all the characteristics capable of causing a future pandemic, according to a study published Monday in the us scientific journal PNAS.

The virus is called G4 and descend genetically from the H1N1 strain caused a pandemic in 2009 : "they have all the essential features showing a high adaptability to infect humans," the authors write, scientists from chinese universities and the Centre for the prevention and fight against disease chinese.