Delaware Reports Presumptive H5 Highly Pathogenic Avian Influenza in Kent County Commercial Flock

The Delaware Department of Agriculture (DDA) has announced a presumptive positive case of H5 highly pathogenic avian influenza (HPAI) in a commercial broiler flock located in Kent County.

The affected premises have been quarantined, and birds on the property are being depopulated in accordance with state and federal response protocols. Officials confirmed that birds from the affected flock will not enter the food supply.

This marks the first detection of avian influenza in a Delaware commercial poultry flock during the 2025–2026 waterfowl migratory season.

Epidemiology and Surveillance

Avian influenza is a highly contagious viral respiratory disease that spreads rapidly among birds via respiratory secretions, ocular discharge, and feces. Transmission can occur:

• Directly between birds

• Indirectly via contaminated equipment, vehicles, footwear, and clothing

• Between domestic poultry and wild migratory birds, particularly waterfowl

The DDA conducts daily active surveillance for avian influenza in collaboration with the University of Delaware laboratory system. Surveillance includes:

• Commercial poultry operations

• Backyard and exhibition flocks

• Livestock and poultry auctions

Biosecurity Guidance for Veterinarians to Reinforce with Clients

Veterinarians working with commercial and backyard poultry owners should emphasize strict biosecurity measures, including:

• Preventing contact with wild and migratory birds, especially waterfowl

• Thorough disinfection of equipment, vehicles, footwear, and tools before flock contact

• Immediate isolation of birds showing signs of illness and prompt veterinary consultation

• Restricting farm access to essential personnel only

• Avoiding commingling with other poultry owners

• Tracking and documenting movement of people, animals, and vehicles on and off premises

Commercial producers should follow company-specific disease reporting protocols immediately upon noticing clinical signs.

Guidance for Backyard Flocks and Wildlife Encounters

Backyard flock owners in Delaware who observe unusual illness or mortality should contact:

• Email: poultry.health@delaware.gov

• Delaware Poultry Health Hotline: 302-698-4507

Reports should include flock size, location, and clinical concerns.

Sick or dead wild birds should be reported through the DNREC Division of Fish and Wildlife sick and injured wildlife reporting system.

Public Health Considerations

While H5N1 has infected a small number of people in the U.S., state health officials emphasize that risk to the general public remains low. Human cases are typically associated with occupational or direct contact with infected birds.

Public health officials recommend that children, immunocompromised individuals, those with chronic health conditions, and pets be kept away from wild birds and bird droppings.

Poultry and poultry products remain safe to consume when properly handled and cooked.

Avian Influenza: Clinical and Virologic Overview

Avian influenza is caused by influenza A viruses, which infect domestic poultry and many wild bird species. Viruses are classified based on:

• Hemagglutinin (H) proteins (H1–H16)

• Neuraminidase (N) proteins (N1–N9)

Different H/N combinations define subtypes, which are further categorized by pathogenicity:

• Low pathogenic avian influenza (LPAI)

• Highly pathogenic avian influenza (HPAI), which can cause severe disease and high mortality in poultry