Avian influenza
Avian influenza, or avian flu or bird flu, is caused by the influenza A virus, which primarily effects infects birds but can also infect mammals, including humans.Wild aquatic birds are the most prevalent host of the influenza A virus, which is an enzootic disease among avian populations.
Avian influenza clinical signs depend on the strain of virus causing the infection, as well as, the species of bird or mammal impacted. Low pathogenic avian influenza (LPAI) and high pathogenic avian influenza (HPAI) classification is based upon the clinical signs observed in domestic chicken(s), and does not provide any prediction of clinical severity in other species.Chickens infected with LPAI will have mild clinical signs or no clinical signs at all and chickens infected with HPAI will show significant respiratory distress, drastic reduction in egg production, and sudden death. Vaccinations may afford domestic poultry some protection from certain strains of the virus.
Human or mammalian infections from avian influenza is limited to severe and prolonged close association with infected birds.Symptoms of infection may be mild to severe, with patients exhibiting fever, diarrhea, and cough.
Influenza A virus is shed from infected birds, in their saliva, mucus, and feces; infected animals may shed bird flu viruses in respiratory secretions and other body fluids. The potential of the virus to spread within poultry flocks and wild birds is rapid. A virulent strain, the influenza A virus (subtype H5N1), has the potential to wipe out domesticated poultry stocks and an estimated half billion farmed birds have been slaughtered in efforts to control the virus.
