Proposed U.S. poultry and egg industry vaccination plan for HPAI
A working group comprising Drs. John Clifford, Craig Rowles, Travis Schaal, and David Swayne distributed a proposed vaccination plan, dated April 1, 2025, to address the ongoing outbreak of highly pathogenic avian influenza (HPAI) affecting the U.S. egg industry. The working group was convened by the United Egg Producers and the American Egg Board, representing U.S. egg producers.
Main Points and Operative Conclusions:
- The extensive biosecurity measures implemented following the 2014–2015 HPAI outbreaks and subsequent mass culling have proven insufficient. Since 2022, over 131 million egg-laying hens have been depopulated, leading to significant egg production shortages.
- The plan advocates a vaccination strategy designed to complement existing biosecurity measures. Vaccination aims to enhance resistance to the H5N1 HPAI virus, reduce viral shedding, and minimize environmental contamination—key to preventing viral mutations with potential implications for human health.
- Vaccination of chicks at hatcheries is considered more practical than vaccinating hens in lay, which presents operational challenges, particularly in cage-free systems. Currently available vaccines require individual injection for each bird.
- A targeted regional vaccination strategy, based on defined “vaccination zones,” is recommended. This approach focuses on egg-laying chickens and turkeys and seeks to preserve international trade by allowing the presentation of vaccinated flocks to trading partners, thereby mitigating trade disruptions.
- The proposed program involves the use of USDA-licensed vaccines, beginning with initial vaccination of day-old chicks followed by booster doses during the grow-out phase, aiming to establish flock-level immunity within 12–18 months.
- Continuous monitoring of vaccine effectiveness is essential. This includes serological testing for specific antibodies and active virus surveillance to detect infections in vaccinated flocks.
- The use of vaccination in poultry has been shown to reduce the risk of human infections associated with HPAI, primarily by decreasing the need for depopulation through reduced viral transmission.
Conclusion:
The implementation of a vaccination plan is considered essential for improved management of HPAI outbreaks in the egg industry. It seeks to protect both poultry and human health by reducing infection rates and virus transmission. The strategy reflects lessons learned from past outbreaks and represents a proactive, preventive enhancement of poultry biosecurity.
This closely reflects the strategy we suggested should be implemented.
