Influenza viruses are enveloped, single-stranded RNA viruses belonging to the Orthomyxoviridae family. The viral genome is composed of eight gene segments of negative sense single-stranded RNA. The viral envelope is coated with surface projections, comprised predominantly of the hemagglutinin (HA) and neuraminidase (NA) proteins, which are also major antigenic determinants. Avian Influenza Virus (AIV) is a contagious viral pathogen affecting many species of birds throughout the world. Clinical signs of Avian Influenza (AI) vary from mild respiratory distress to death in chickens, while wild birds are generally asymptomatic. The highly pathogenic H5N1 subtype has been associated with the infection of humans in Southeast Asia and Africa who have come in direct contact with infected birds. These concerns persist as human infections with an avian H7N9 virus were first reported in 2013.
Last date updated on June, 2014