Post-vaccination surveillance is crucial for rapidly detecting outbreaks of avian influenza and proving the absence of disease, to enable the safe movement of birds, according to an opinion from the European Food Safety Authority (EFSA) published on Wednesday 17 April.
The European Commission has asked EFSA to provide a comprehensive overview of effective surveillance options and risk reduction measures for avian influenza.
In the case of emergency vaccination against highly pathogenic avian influenza (HPAI), the scientists concluded that, to be effective, surveillance programmes aimed at the early detection of new outbreaks had to take into account the type of poultry and the size of the flock. If vaccination is preventive, it is recommended that monthly virological tests be carried out on a maximum of 15 dead birds to demonstrate the absence of disease and to ensure the safe movement of poultry and poultry products. In addition, vaccinated and unvaccinated flocks must be passively monitored.
Experts from the EU Reference Laboratory and EFSA worked closely together to recommend the most appropriate diagnostic tests for surveillance depending on the type of vaccine, the vaccination strategy (i.e. emergency or preventive) and the extent of surveillance (see EUROPE 13269/28). More sensitive methods should be used when the amount of virus in the blood is likely to be low due to vaccination.
Link to opinion: https://aeur.eu/f/bt7 (Original version in French by Lionel Changeur)