Beijing, April 10 : A top Chinese biology lab Wednesday ascribed the H7N9 avian influenza to genetic reassortment of wild birds from east Asia and chickens from east China.

The researchers found that no genes in H7N9 were traceable to pigs, thus excluding pigs as intermediate hosts for the deadly new strain of bird flu, reports Xinhua.

The report came from the Chinese Academy of Sciences' Key Laboratory of Pathogenic Microbiology and Immunology.

A fresh outbreak of bird flu in China has killed nine people.(IANS)