Avian influenza is a viral pandemic disease of humans and birds, including commercial and house poultry. Avian influenza is a major concern around the world, which causes serious economic losses in the poultry industry, mainly in home backyard poultry. The backyard poultry is the potential source of income for rural people and indirectly contributes to decreasing the poverty of household women. Besides, in many developing countries, villagers full fill a part of their food demand by the backyard poultry; however, this sector is directly affected by biosecurity risks, including high and low pathogenic avian influenza infections like avian influenza H9N2 subtype. Avian influenza H9N2 subtype has low pathogenic zoonotic importance but still causes serious threats to the poultry industry. The backyard poultry industry is directly affected by this infection due to direct contact with wild migratory birds locating in different regions of the world. Antigenic drift and shift are one of the major conflicts of this infection resulting from a few days to a few months up to many years and also the main reason for the uncontrollable mutation in this infection. All over the world, there is no serious action taken to prevent the H9N2 subtype infection in backyard poultry. This situation has become severe because of the widespread of highly pathogenic avian influenza viruses in the past few years.
Molecular Survey of Respiratory and Immunosuppressive Pathogens Associated with Low Pathogenic Avian Influenza H9N2 Subtype and Virulent Newcastle Disease Viruses in Commercial Chicken Flocks
