The United States Department of Agriculture’s Animal and Plant Health Inspection Service (APHIS) has confirmed the presence of highly pathogenic avian influenza (HPAI) in a non-commercial backyard flock (non-poultry) in Knox County, according to a press release.

Samples from the flock were tested at the Cornell University Animal Health Diagnostic Center, part of the National Animal Health Laboratory Network, and confirmed at the APHIS National Veterinary Services Laboratories (NVSL) in Ames, Iowa.

APHIS is working closely with state animal health officials in Maine on a joint incident response, the release stated.

State officials quarantined the affected premises, and birds on the properties will be depopulated to prevent the spread of the disease. Birds from the flock will not enter the food system.

According to the U.S. Centers for Disease Control and Prevention, the recent HPAI detections in birds do not present an immediate public health concern. No human cases of these avian influenza viruses have been detected in the United States. The proper handling and cooking of poultry and eggs to an internal temperature of 165 ˚F kills bacteria and viruses.

As part of existing avian influenza response plans, federal and state partners are working jointly on additional surveillance and testing in areas around the affected flock. The United States has the strongest AI surveillance program in the world, and USDA is working with its partners to actively look for the disease in commercial poultry operations, live bird markets and in migratory wild bird populations.

APHIS will continue to announce the first case of HPAI in commercial and non-commercial backyard flocks detected in a State but will not announce subsequent detections in the state, per the release. All cases in commercial and non-commercial backyard flocks will be listed on the APHIS website. 

Avian influenza (AI) is caused by an influenza type A virus which can infect poultry (such as chickens, turkeys, pheasants, quail, domestic ducks, geese, and guinea fowl) and is carried by free flying waterfowl such as ducks, geese and shorebirds. AI viruses are classified by a combination of two groups of proteins: hemagglutinin or “H” proteins, of which there are 16 (H1–H16), and neuraminidase or “N” proteins, of which there are 9 (N1–N9).

Many different combinations of “H” and “N” proteins are possible. Each combination is considered a different subtype and can be further broken down into different strains which circulate within flyways/geographic regions. AI viruses are further classified by their pathogenicity (low or high)—the ability of a particular virus strain to produce disease in domestic poultry.