IPSF: Potential vaccine against H5 HPAI in turkeys
An H5N9 inactivated avian influenza vaccine was evaluated for its efficacy in turkeys
11 March 2025
1 minute read
By: The unprecedented outbreak of clade 2.3.4.4b H5N1 highly pathogenic avian influenza virus (HPAIV) in United States has caused tremendous damage to the poultry industry. Because turkeys have the highest number of affected individual flocks among commercial poultry, evaluating vaccine efficacy and characterizing antibody response of turkeys is crucial.
Jiho Lee, Scott Lee, Erica Spackman and Chang-Won Lee, USDA, SERPL, Athens, Georgia, USA, presented the results of a vaccine evaluation during the 2025 International Poultry Scientific Forum.
An in-house reverse-genetics generated H5N9 inactivated vaccine (SEP-22- N9) was evaluated for its vaccine efficacy in turkeys against current North American clade 2.3.4.4b H5 isolate, A/turkey/Indiana/22-003707-003/2022 H5N1.
Vaccination groups were divided into three groups, which were vaccinated at different time points (3, 7, or 9 weeks). All vaccinated groups showed 100% survival rate and significantly reduced viral shedding after the challenge when compared to the sham vaccinated group.
The enzyme linked lectin assay-neuraminidase inhibition (ELLA-NI) was applied to assess the capability of detecting birds that have been infected after the vaccination (DIVA-VI). Overall, the SEP22-N9 vaccine provided fast onset of immunity to protect turkeys from mortality, reduced viral shedding, and was able to apply ELLA-NI assay for DIVA-VI, demonstrating that the vaccine could be used against currently circulating clade 2.3.4.4b H5 HPAIVs.
