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Avian Flu VirusAbout Flu: Avian Flu

 • What is it?
 • Symptoms
 • History


What is Avian Flu?

H5N1 (Bird) flu virus is an influenza A virus subtype that is highly contagious among birds, and can be deadly to them. The H5N1 (Bird) flu virus does not usually infect people, but rare infections with these viruses have occurred in humans. Nearly all human cases have resulted from people having direct or close contact with H5N1-infected poultry or H5N1-contaminated surfaces.

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Symptoms of the H5N1 (Bird) flu virus in humans have ranged from typical human influenza-like symptoms (e.g., fever, cough, sore throat, and muscle aches) to eye infections, pneumonia, severe respiratory diseases (such as acute respiratory distress), and other severe and life-threatening complications. The symptoms of H5N1 (Bird) flu may depend on which virus caused the infection.

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Outbreaks of highly pathogenic avian influenza A (H5N1) associated with illness and death in humans have occurred in Asia since late 2003. In the United States, different avian influenza viruses caused outbreaks among poultry in 2003 and 2004, and one human infection in 2003.

Learn more here (Exit Disclaimer) for a more in depth account of avian flu history.

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