Avian influenza, or better known as H5N1 or bird flu, is a type A flu virus that is highly contagious among birds. This virus does not usually infect humans, but certain cases have been reported. Nearly all the cases reported have resulted in people who had direct or close contact with H5N1 infected poultry or H5N1 contaminated surfaces. Bird flu is not considered to be a pandemic, but the threat of an H5N1 epidemic is possible. More than 500 cases of human infection have been reported since 2003 in countries in Asia, Africa, the Pacific, Europe and the Near East. Indonesia, Vietnam and Egypt have the highest number of H5N1 bird flu cases to date.
It is important to note that H5N1 (Bird flu) viruses have never been detected among birds or people in the United States.