Colder Weather is Migratory Bird Season and Avian Flu Season

Delaware Agriculture officials remind residents to be diligent on poultry safety as the colder weather marks the start of the 2026-27 migratory bird season – which can also bring an increase in avian influenza cases. Avian or bird flu is a highly contagious airborne respiratory virus that spreads quickly among birds from flock to flock – including wild birds. Besides infected poultry – the virus can also be spread through equipment and the clothing and shoes of caretakers.  The virus affects poultry, like chickens, ducks, and turkeys, as well as some wild bird species, such as ducks, geese and shorebirds.

One case of H5N1 avian flue has been confirmed at a commercial broiler farm in Worcester County. All poultry owners should increase vigilance in protecting their flocks from contracting avian flu.

Additional information from DDA:

The Delaware Department of Agriculture, with the help of the University of Delaware laboratory system, performs active surveillance and testing of birds for avian influenza within the state every day. Surveillance is conducted at commercial and backyard poultry operations, prior to exhibitions, and at livestock and poultry auctions.

The Delaware Department of Agriculture requires the registration of all locations where live poultry is kept, which allows timely information on disease incidents to be sent to all poultry producers. Registration forms are available online at https://de.gov/poultry.

Key Tips:

All poultry owners should increase their vigilance in protecting their flocks from contracting avian influenza by following these steps:

• Exclude your flock from spaces where wild or migratory birds, especially waterfowl, have access.
• Disinfect equipment, vehicles, footwear, and other items prior to contact with flocks.
• Isolate any animals with signs of illness and contact your veterinarian.
• Permit only essential workers and vehicles to enter the farm to limit the chances of bringing the virus from an outside source.
• Avoid visiting other poultry farms and any unnecessary travel off the farm.
• Limit, monitor and record any movement of people, vehicles or animals on or off your farm.

Delaware backyard flock owners who notice dead birds or any unusual signs in their flock should email poultry.health@delaware.gov or call the Delaware Poultry Health Hotline at 302-698-4507 and provide your contact information, size of flock, location, and concerns. Find helpful tips here: https://agriculture.delaware.gov/poultry-animal-health/avian-flu-graphics/.

Commercial poultry producers should follow the procedures of contacting the company they grow for when they notice signs of disease.

If you see a sick or dead wild bird on public or private property, report sightings through the Delaware Department of Natural Resources and Environmental Control’s Division of Fish and Wildlife’s sick and injured wildlife reporting form. 

All Delawareans, especially waterfowl hunters, are reminded to not handle obviously sick or dead wild birds. Hunters are encouraged to practice biosecurity practices. Review a fact sheet here: https://www.aphis.usda.gov/sites/default/files/fsc_hpai_hunters.pdf

AI Breakdown:

AI is caused by an influenza type A virus that can infect poultry (such as chickens, turkeys, pheasants, quail, domestic ducks, geese, and guinea fowl) and is carried by free-flying waterfowl and wild birds, such as ducks, geese, raptors, 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 combinations of “H” and “N” proteins are possible.

Each combination is considered a different subtype and can be further broken down into different strains that 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.