Governments, often shy to use vaccination due to the trade restrictions it can entail, have increasingly considered adopting the measure due to the devastation bird flu can cause to flocks and to limit the risk of potential transmission between humans.

“Preventive vaccination is the optimal vaccination strategy to minimise the number of outbreaks and duration of epidemic and should be conducted in the most susceptible and infectious poultry species in high-risk transmission areas,” the Efsa said in a scientific opinion published on its website.

The opinion comes after France last week became the first EU country and the world’s first large poultry exporter to launch a nationwide bird flu vaccination campaign.

The Efsa also recommended that, in the event of an outbreak, emergency protective vaccination should be carried out within a 3km radius of the outbreak in high-risk transmission areas.

Vaccination should complement and not replace other preventive and control measures, such as infection monitoring in birds, early detection, and biosecurity, and is recommended as part of an integrated disease control approach, it added.

The European Commission had asked the Efsa to give an overview of the available bird flu vaccines, their efficacy against current viruses, and to assess various vaccination schemes to help member states decide on their vaccination strategies as and when they become necessary, the Efsa said.

A separate opinion on surveillance and risk mitigation measures in vaccinated areas and farms is expected in March 2024.

Bird flu usually strikes during the autumn and winter. It is transmitted by infected migrating wild birds’ faeces or direct contact with contaminated feed, clothing, and equipment.