Avian influenza is also known as bird flu. It is an infection caused by avian (bird) influenza (flu) viruses. These viruses occur naturally among wild birds worldwide in their intestines, but they do not get sick . It is very contagious among birds including domestic birds eg. chickens, ducks & turkeys and kill them. Virus are excreted from infected birds in their saliva, nasal secretions, & feces. Birds including domestic ones become infected through direct contact with other infected poultry, or through contact with infected surfaces (such as dirt or cages) or materials (such as water or feed).