France monitors Aujeszky’s vaccine effects in hunting dogs

The French Federation of Hound Hunting Associations (FACCC, by its French initials) has asked owners of dogs vaccinated against Aujeszky’s disease to report any possible side effects and to respond even when their animal shows no reaction. The appeal, issued by the organisation itself and reported by Le Chasseur Français, is part of a study into vaccination tolerance in hunting dogs.

The FACCC has made two questionnaires available: one must be completed between 10 and 15 days after the first injection and the other within the same period after the booster dose, administered approximately three weeks later. The federation asks owners to record the nature of any signs observed, when they appeared, how long they lasted and whether they required a veterinary consultation.

Why owners of dogs with no reactions should also respond

The data collection is not limited to animals that have experienced discomfort. The FACCC stresses that it also needs to know how many dogs show no adverse effects. This information is necessary to estimate the proportion of animals without reactions and assess product tolerance more rigorously.

This distinction is important: launching the questionnaires does not amount to a health alert, nor does it prove that the vaccine is causing a new problem. It is an observational data-gathering exercise promoted by an industry organisation. The appeal has also yet to provide the planned sample size, full methodology, duration of follow-up or consolidated results.

The survey is also no substitute for official veterinary pharmacovigilance channels. The French Agency for Food, Environmental and Occupational Health & Safety, Anses, explains that reports of adverse events help detect new signals and better characterise the frequency or severity of known reactions. If any clinical signs occur after vaccination, assessment is the responsibility of a veterinarian, who can submit a report through the regulatory channels.

A risk linked to contact with wild boar

French hunters’ interest in this vaccination stems from the persistence of the virus in wild boar. The latest available Anses review indicates that France retains its disease-free status for pig farms, although the pathogen continues to circulate in wildlife and regularly affects hunting dogs following contact with infected animals.

In 2024, the French National Reference Laboratory detected genetic material from the virus in 53 dogs out of 66 investigated following clinical suspicion. The Anses epidemiological assessment states that they were generally hunting dogs and that none of the cases was linked to a pig farm.

In its public announcement, the FACCC does not identify the brand name or publish the product information for the vaccine being monitored. Before protocols, contraindications or expectations of protection can be applied elsewhere, it will therefore be necessary to confirm which vaccine was used and the terms of its current authorisation in France. The survey may broaden the available knowledge about its tolerance, but on its own it cannot establish its definitive safety or its effectiveness against real-world exposure to the virus.