Description
Influenza A virus subtype H7N9 (A/H7N9) is a bird flu strain of the species Influenza virus A. Avian influenza A H7 viruses normally circulate amongst avian populations with some variants known to occasionally infect humans.
WHO has identified H7N9 as an unusually dangerous virus for humans. Most of the cases resulted in severe respiratory illness, with a mortality rate of roughly 30 percent.