As Easy as 1, 2, 3: Preventing Avian Influenza Starts with Simple Biosecurity

By Linnea M. Tracy, VMD, MPH, MAM, DACPV

In the era of backyard ‘inflation chickens’, there looms a threat to egg availability even more hazardous than high grocery prices: highly pathogenic avian influenza (HPAI). The wide economic impacts of HPAI on the poultry industry may be one of the reasons the popularity of small flocks continues to grow. Despite the perceived safety of your own backyard, the health of any flocks that reside there is still very much at risk.

The current outbreak situation of HPAI in the United States may now be considered the largest animal health event the country has ever experienced.1 Many of us remember similar circumstances in 2015 with spiking prices of eggs and disturbing headlines about poultry lives lost. For backyard poultry owners and small flock clinicians, the current outbreak is different and more worrisome in two key ways. First, it has continued to infect poultry in the U.S. throughout the year. Second, over 58% of the reported cases have occurred in non-commercial or small flocks.1 For context, just 9% of the 2015 outbreak cases occurred in non-commercial poultry.2 The 2022 strain of the HPAI virus is well adapted to persisting in migratory and resident waterfowl hosts while retaining its infectious potential to domestic poultry. Discussions of virology and regulatory impacts aside, we have a pressing, urgent task upon us to protect our small flocks from this disease risk in Pennsylvania’s backyard.

Following the 2015 avian influenza outbreak, the commercial poultry industry partnered with the USDA to develop biosecurity plans organized around 14 core principles.3 While all fourteen may be applied in small flock management, three are of the utmost importance in protecting small flocks from the threat of HPAI: Line of Separation, Animal Control, and Visitor Control.

(1) Line of Separation

Establishing a definite boundary around your flock’s space is the best way to initiate flock biosecurity. Your line of separation can be a physical wall, the wire of your coop space, or the fence containing your backyard-roaming birds. Setting rules for who and what is allowed to enter your flock’s space can spare them from disease exposure. Fomites (including vehicles, shoes, and equipment) which have been in contact with poultry or wild birds or their feces should be thoroughly cleaned and sanitized before ever crossing the line of separation. The best practice is to have designated footwear for your flock space alone and never to share equipment used in your birds’ space elsewhere. No matter the material, if you cannot confirm it’s clean, don’t take the risk, and don’t bring it over the line.

(2) Animal Control

HPAI has been identified in wild birds in 49 states since the start of this outbreak!1 As the main vector of HPAI and many other pathogens and parasites, minimizing any wild bird contact is a main biosecurity goal for any flock. Prevent your birds from gathering near ponds or water sources where waterfowl may visit, and protect feed troughs and waterers by moving them

Be aware: Highly Pathogenic Avian Influenza (HPAI) HPAI is a deadly disease of poultry spread by wild waterfowl. This disease is federally reportable and has been present in Pennsylvania in 2022 and 2023. If your flock experiences any sudden mortality or any of the following signs without obvious cause, seek out testing through the PA Department of Agriculture:

• Sudden or nonspecific mortality

• Sudden decreases in feed and water consumption

• Lethargy, depression, or neurologic signs

• Respiratory signs (rales, increased respiratory rate or effort, secretions)

• Cyanosis or purple discoloration of non-feathered areas (shanks, wattles, combs)

• Diarrhea

• Frequent soft or shell-less eggs

The Pennsylvania Department of Agriculture hosts a hotline for anyone who is concerned that their or a client’s flock may be infected: 717-772-2852 (press option 1). Call at any time to speak with an expert who can direct you to further resources. Do not move sick birds without a negative AI test result.

For more information, visit: www.agriculture.pa.gov/Animals/ AHDServices/diseases/avian_influenza/Pages/default.aspx or http://padls.agriculture.pa.gov/InnerPages/HPAI.html inside the coop or under a covered area to discourage visits from wild birds. If possible, containing your flock to a covered coop is their best line of defense, as they can contract HPAI from droppings or other materials that may fall as wild carriers fly overhead. Notably, this strain of HPAI has also been isolated from wild mammals such as foxes.1 Thus, burying your coop wire and enclosing your birds at night could not only save them from predation but also a potential AI exposure.

(3) Visitor Control

Visitors make excellent fomites. During times of disease, the safest policy is to treat your flock like an exclusive club–members only. Even essential visitors should only enter your line of separation if they are wearing clean clothes and shoes and have not had any poultry, pet bird, or wild bird contact for 72 hours. Do not be shy to ask folks about bird contact or to cover their shoes with boot covers or bags as they enter your flock area. For vets visiting small flocks, try to space out farm calls days apart, wear shoe covers and coveralls or scrubs, wash your vehicle including an undercarriage wash after each visit, and thoroughly sanitize whatever equipment you bring into the flock area. Remember, a visitor’s bird contact can take a variety of forms including hunting, fishing, zoo trips, and farm visits, but all are risks for exposure of your flock to HPAI.

Despite the perceived safety of the backyard, small flocks nevertheless exist in a global disease ecosystem, and avian influenza remains a dire threat in 2023. Implementing simple biosecurity practices has the potential to save many poultry lives from HPAI as well as from more common poultry diseases.

References:

1) U.S. Department of Agriculture Animal and Plant Health Inspection Service. “2022-2023 Detections of Highly Pathogenic Avian Influenza”. Accessed Feb 10, 2023. https://www.aphis.usda.gov/aphis/ourfocus/ animalhealth/animal-disease-information/avian/avian-influenza/hpai2022

2) U.S. Department of Agriculture Veterinary Services, Surveillance, Preparedness, and Response Services, Animal and Plant Health Inspection Service. “Final Report for the 2014-2015 Outbreak of Highly Pathogenic Avian Influenza (HPA) in the United States. Public Version”. Accessed Feb 10, 2023. https://www.aphis.usda.gov/animal_health/emergency_ management/downloads/hpai/2015-hpai-final-report.pdf

3) National Poultry Improvement Program. “NPIP Program Standards: Standard E- Biosecurity Principles”. Accessed Feb 10, 2023. https://www. poultryimprovement.org/documents/StandardE-BiosecurityPrinciples.pdf

About the Author: Linnea M. Tracy, VMD, MPH, MAM, DACPV, is a boardcertified poultry veterinarian working with a commercial egg company based in Pennsylvania. She completed her poultry specialty training at the University of Georgia, where she gained experience in various poultry species and production styles before returning to Pennsylvania to practice. Dr. Tracy is passionate about poultry medicine and health education for veterinary professionals and students for both backyard and commercialscale flocks. She can be reached at ltracyvmd@gmail.com