New flu in China reveals its avian origins

H7N9 influenza genes came from three bird viruses

A new type of bird flu that has killed 11 people in China combines genes from three existing influenza viruses, scientists report April 11 in the New England Journal of Medicine.

Since Chinese officials confirmed March 29 that three people had contracted H7N9 avian influenza, the virus has sickened 43 people.