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Avian Influenza

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Avian influenza
Avian influenza - ARS scientists are working to improve vaccines and technology to help control bird flu - Photo by Stephen Ausmus; USDA, ARS Image Gallery
Scientific Name: 

Orthomyxoviridae, Influenza Type A (CABI)

Common Name: 

Highly pathogenic avian influenza (HPAI), fowl plague

Native To: 

First noted in Italy in 1878 (CABI)

Date of U.S. Introduction: 


Means of Introduction: 

Projected to arrive in the U.S. in migratory birds or through poultry imports (Global Invasive Species Database 2005)


Infects poultry, waterfowl, and occasionally mammals (including humans) (CABI)

Current U.S. Distribution: 
Not currently established in the U.S.


USDA. Animal and Plant Health Inspection Service.

The United States Department of Agriculture's (USDA) Animal and Plant Health Inspection Service (APHIS) has confirmed highly pathogenic Eurasian H5 avian influenza (HPAI) in a wild American wigeon in Colleton County, South Carolina. Eurasian H5 HPAI has not been detected in a wild bird in the United States since 2016. There was a case of HPAI (H7N3) in one commercial meat turkey flock in South Carolina in 2020 due to a North American lineage virus. The Centers for Disease Control and Prevention considers the risk to the general public from HPAI H5 infections to be low. No human infections with Eurasian H5 viruses have occurred in the United States. As a reminder, the proper handling and cooking of poultry and eggs to an internal temperature of 165˚F kills bacteria and viruses, including HPAI.

Anyone involved with poultry production from the small backyard to the large commercial producer should review their biosecurity activities to assure the health of their birds. APHIS has materials about biosecurity, including videos, checklists, and a toolkit available at the Defend the Flock Resource Center.

USDA. Animal and Plant Health Inspection Service.

The United States Department of Agriculture’s (USDA) Animal and Plant Health Inspection Service (APHIS) has confirmed the presence of highly pathogenic H7N3 avian influenza (HPAI) in a commercial turkey flock in Chesterfield County, South Carolina. This is the first confirmed case of HPAI in commercial poultry in the United States since 2017. It appears this HPAI strain mutated from a low pathogenic strain that has been found in poultry in that area recently. No human cases of this H7N3 avian influenza virus have been detected and there is no immediate public health concern. All bird owners, whether commercial producers or backyard enthusiasts, should continue to practice good biosecurity, prevent contact between their birds and wild birds, and report sick birds or unusual bird deaths to State/Federal officials, either through their state veterinarian or through USDA’s toll-free number at 1-866-536-7593. Additional information on biosecurity for can be found at

USDA. Animal and Plant Health Inspection Service.

Avian influenza, or "bird flu," is a respiratory disease of birds caused by influenza A viruses. These viruses can infect domestic poultry (such as chickens, turkeys, ducks, and geese) and are found naturally in wild birds (such as ducks, gulls, and shorebirds). Low pathogenic avian influenza (LPAI) occurs naturally in wild birds and can spread to domestic birds. In most cases, it causes few or no outward signs of infection. LPAI viruses are common in the United States and around the world. High pathogenic avian influenza (HPAI) is extremely infectious, often fatal to domestic poultry, and can spread rapidly from flock to flock. If HPAI is found in the United States, we must eradicate it to protect our country’s flocks and to keep trade flowing.

Distribution / Maps / Survey Status

USDA. Animal and Plant Health Inspection Service.
Includes current HPAI and previous findings and outbreaks.
UN. World Health Organization.
Select "avian influenza" from topic list; also provides maps by geographic area.
DHHS. Centers for Disease Control and Prevention.
Provides situation summaries by type (wild birds, poultry, humans) and location.

Federally Regulated


Iowa State University. Center for Food Security and Public Health.


Google. YouTube; Truffle Media Networks.
Presentation by Dr. Jack Shere, DVM, PhD, Associate Deputy Administrator APHIS Veterinary Services, from the 2015 NIAA Annual Conference titled 'Water and the Future of Animal Agriculture', held Mar 23-26, 2015 in Indianapolis, Indiana.

Google. YouTube; Penn State Extension.

Selected Resources

The section below contains highly relevant resources for this species, organized by source. Or, to display all related content view all resources for Avian Influenza.


World Organisation for Animal Health.

UN. FAO. Animal Production and Health Division.

IUCN. Species Survival Commission. Invasive Species Specialist Group.
Federal Government
USDA. Animal and Plant Health Inspection Service.
DOI. USGS. National Wildlife Health Center.
Provides news updates and other resources
U.S. Department of Agriculture.
USDA. Agricultural Research Service.
DHHS. Centers for Disease Control and Prevention.

United States Department of Labor. Occupational Safety and Health Administration.

International Government
State and Local Government

New Jersey Department of Agriculture.

Utah Department of Natural Resources. Division of Wildlife Resources.

Virginia Department of Wildlife Resources.

Provides guidelines for hunters and individuals finding dead birds

Pennsylvania Game Commission.
Provides facts about bird flu and wild birds, answers to common questions and links to more detailed information

Mississippi State University. Extension.

University of Pennsylvania. School of Veterinary Medicine. Wildlife Futures Program.

Ohio State University. College of Food, Agricultural, and Environmental Sciences.

Iowa State University. Center for Food Security and Public Health.

Pennsylvania State University. Cooperative Extension.

Cornell University. Cornell Wildlife Health Lab.

University of Florida. Institute of Food and Agricultural Sciences Extension.

Electronic Data Information Source Publication #PS38

American Veterinary Medicine Association.