Avian influenza (AI), or bird flu, is a group of viruses that affect wild and domestic birds. The viruses are only found in a small number of birds in the wild, usually waterfowl and shorebirds, and rarely cause disease in these birds. The viruses are transmitted in fecal droppings, saliva, and nasal discharges. An infected bird is not a sign of a pandemic.
Since 2003, a form of bird flu has has been detected throughout Asia, parts of Europe, and Northern Africa. This highly pathogenic avian influenza (HPAI) H5N1 virus has resulted in the deaths of millions of domestic poultry, most euthanized to prevent spread of the illness. While very rare, this particular virus has also infected some people who have had close direct contact with sick birds. This H5N1 virus causing illness in other parts of the world has not been detected in wild birds, domestic poultry, or humans in Wisconsin or North America.
Currently, most human H5N1 infections are thought to be from close contact with infected poultry or contaminated materials, or by eating uncooked poultry products, not through wild bird to human transmission.
The actual number of human cases and fatalities due to H5N1 is low when compared to the 36,000 deaths annually just in the U.S. from seasonal influenza viruses. One concern, however is the high death rate in those people who are have become sick with H5N1. Additionally, there is worry that with human infection, the H5N1 virus could evolve to spread more easily among people, triggering a worldwide influenza pandemic.
Maps
Maps from the WHO documenting the spread of H5N1 avian influenza in humans, poultry, and wild birds.
Additional Information 
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