No current vaccine meets the full criteria for deployment to tackle the UK's ongoing bird flu outbreak, the avian influenza vaccination task force says.
As the UK enters the fourth season of regular outbreaks of highly pathogenic avian influenza (HPAI), there is a growing call among farmers for control measures that extend beyond just 'robust biosecurity.'
The AI task force, a joint industry and cross-party government group, was established to explore these options and develop recommendations for using vaccination in poultry as a preventive measure against HPAI.
Given the worsening UK disease situation and global developments, the task force has provided an update detailing its activities, current policy, vaccine development and approval processes, trade implications, and next steps.
The joint statement is endorsed by the four devolved administrations, the Veterinary Medicines Directorate, the Animal Plant and Health Agency, and all major trade associations in the poultry sector.
Currently, vaccination against HPAI in poultry and captive birds is not permitted, except for some licensed zoos.
While vaccines can reduce mortality and clinical signs, they do not eliminate the risk of infection or transmission, and may complicate detection, thus increasing the risk of spreading the virus, the task force says.
The development of a Differentiating Infected from Vaccinated Animals (DIVA) strategy to monitor vaccinated flocks and distinguish between field and vaccine strains remains a core focus of the task force and is subject to ongoing research.
Discussions are also taking place regarding how the game bird industry may be integrated into a vaccination and surveillance program.
The task force says that implementing such a strategy is central to the UK's ability to trade poultry products internationally, as the country must assure trade partners that effective safeguards are in place.
Although vaccination is not a barrier to safe international trade according to World Organisation for Animal Health (WOAH) guidelines, many countries impose restrictions on goods when vaccination has been used, and this practice is likely to continue.
Currently, there are two authorized bird flu vaccines in the UK, neither of which contains subtype H5N1 as an active component.
Several applications for H5-subtype vaccines are under assessment by the Veterinary Medicines Directorate (VMD), the authority responsible for approving the marketing of such pharmaceuticals.
Several HPAI vaccines have already received international approval, including one in the European Union that claims efficacy against H5.
The task force says it will analyse these vaccines, but the interim statement, published on Friday (7 March), emphasises that a complete solution is not forthcoming.
The statement says: “Selecting the appropriate vaccine is a critical step when considering vaccination and will depend on various criteria relevant to the local situation.
"No current vaccine or vaccine technology fully meets all these criteria.”
Gary Ford, head of strategy at the British Free Range Egg Producers' Association (BFREPA), said the statement raised awareness that, at this point, vaccination was not yet a complete solution.
"This winter has seen over 40 cases of HPAI, resulting in significant financial impacts, distress for affected businesses, and disruption across the poultry sector," Mr Ford said.
"This situation has sparked considerable interest in avian flu vaccines, both from the industry—where vaccines are routinely used to protect flocks from endemic diseases—and the media.
“As members of the joint industry and cross-government AI vaccination task force, we welcome this timely statement as an opportunity to highlight the opportunities and challenges associated with vaccination.
"Furthermore, we need a full understanding of vaccine protection for flocks kept longer on-farm, given the inability to vaccinate in-lay."
He concluded: “Despite these challenges, BFREPA strongly supports vaccination as a key tool for protecting our flocks against this insidious disease, alongside stringent biosecurity measures."
The AI task force will publish a more detailed report in summer 2025.
