Avian influenza and the implication for human infection

Highly pathogenic avian influenza due to H5N1 virus has decimated poultry flocks throughout the eastern hemisphere and resulted in over 600 human infections. Despite the H5N1 virus being endemic in several Asian countries, with ongoing human exposure and infection, efficient human-to-human transmission has not been reported. There is much concern over the pandemic potential of this virus should this transmissibility develop due to its widespread circulation, continued evolution and recent research showing relatively few mutations are needed for airborne mammalian transmission. It is unknown whether the emergence of such a mutated H5N1 virus would cause a pandemic owing to uncertainties of how the virus would behave in humans.