The genetic heritage of the new H7N9 influenza virus is 100% of bird origin; to this day April 16, 2013, this virus has caused 60 influenza cases and made 13 victims, at least according to official data provided by Chinese authorities. Spreading from the eastern regions around Shanghai, it has already reached Beijing. The in-depth genetic analysis of the first three cases, all of them fatal, described in the New England Journal of Medicine confirmed that all these viruses' genes, never reported before, are of avian origin.
Influenza A cases, of the H7 type, already infected humans in the past,