Avian Influenza


Avian influenza refers to the disease caused by infection with avian influenza Type A viruses. These viruses naturally spread among wild waterfowl worldwide and can infect domestic poultry and other bird and animal species. Avian flu viruses do not normally infect humans. However, occasional human infections with avian flu viruses have occurred.

There are 15 known avian influenza virus subtypes circulating in bird populations. The severity of the disease depends on the subtype that infects the birds. The illness can sometimes be mild, resulting only in ruffled feathers or reduced egg production. Illness can also become what is known as “highly pathogenic avian influenza." This latter form is extremely contagious in birds and quickly fatal. Millions of domestic birds have been destroyed in the last few years in an attempt to control the spread of the viruses to animals and humans.

General Information & Resources

Mailing Address

Disease Surveillance and Epidemiology Section
Mail Code: 3082
P.O. Box 149347
Austin , TX 78714-9347
United States

Physical Address

Disease Surveillance and Epidemiology Section
Moreton Building, Suite M-631
1100 West 49th Street
Austin , TX 78756-3199
United States